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Obesity: Comfort vs. Discontent Book · April 2016
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Obesity Comfort vs. Discontent
David F Marks PhD
Obesity Comfort vs.Discontent Copyright David F Marks
 Published: 18 April 2016 Yin and Yang Books ISBN-13: 978-1532762963 ISBN-10: 1532762968
The right of David F Marks to be identified as author of this Work has been asserted by him in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in retrieval system, copied in any form or by any means, electronic, mechanical, photocopying, recording or otherwise transmitted without written permission from the author.
Š David F Marks Yin and Yang Books All rights reserved
Dedication To the two-point-one billion people who are overweight or living with obesity. Please take note: It is not your fault, you are not to blame, you are the victims. be informed, be empowered, and, above all else, resist. This book is for you.
Table of Contents
Preface Summary One: Obesity............................................................1 Two: Dyshomeostasis............................................15 Three: Evidence.....................................................45 Four: Neurobiology.................................................69 Five: Addictions......................................................89 Six: Motivation......................................................101 Seven: Prevention..…..........................................109 Eight: Questions...................................................135 Nine: Conclusions................................................147 References...........................................................153
Preface Inside every one us there exists a tension between comfort and discontent. When we assuage the discontent, we find comfort. When we resist comfort, the discontent builds stronger. This eternal struggle is an aspect of the human condition that creates in many a vicious and unforgiving circle. Within it lies the key to human nature, to the nature of all sentient beings, the 'Yin and Yang' of life. Of relevance to the topic of this book, it helps to explain the human struggle with overweight, obesity and the addictions. Once the causes of obesity are fully understood, the obesity epidemic can be stopped. This book takes a step towards that goal. I propose an explanatory theory of an objective issue of undeniable importance to human beings – the obesity epidemic. The ideas are drawn from a range of disciplines including economics, endocrinology, epidemiology, neurobiology, nutrition, physiology, policy studies and psychology. The theory focuses on a universal feature of living beings, homeostasis, and the potential for its disruption, dyshomeostasis. The evidence points to 'Obesity Dyshomeostasis' as a problematic human response to contemporary living conditions. Similar to racism, sexism and ageism, the current trend towards blaming and shaming individual sufferers of obesity and overweight contributes to the problem. Only by reversing this
oppressive prejudice, reforming the food environment, and improving the chronically stressful living conditions, does the obesity epidemic have any chance of being resolved (Marks, 2015a, 2016). My interest in the social and political significance of obesity grew when a Special Issue I edited of the Journal of Health Psychology on “Food, diets and dieting� was published (Marks, 2015b). The topic generated so many high quality articles that we published, not one but, two large special issues. In spite of all this scholarly work, however, it became clear that no genuinely explanatory theory of obesity actually existed. This stimulated two pieces in Health Psychology Open in which I proposed the theory of the 'Circle of Discontent'. I thank my colleagues on the Editorial Board of Journal of Health Psychology and Health Psychology Open, two journals for which I serve as Editor, and Kerry Barner at SAGE Publications Ltd for her generous support. I also warmly thank the following scholars for their insightful comments on an earlier version of Obesity Dyshomeostasis Theory: Rachel Annunziato, Kristin August, Lindzee Bailey, Laszlo Brassai, Emily Brindal, Janine Delahanty, Carlo DiClemente, Stephanie Grossman, Camille Guertin, Charlotte Markey, Patrick Markey, Jennifer Mills, Christopher Nave, Luc Pelletier, Bettina Piko, Paige Pope, Meredith Rocchi, Kaley Roosen, Diane Rosenbaum, Kamila White and Gary Wittert.
Summary Health is regulated by homeostasis, a property of all living things. Homeostasis maintains equilibrium using feedback loops for optimum functioning of the organism. Dyshomeostasis, a disturbance of homeostasis, causes overweight and obesity, estimated to be present today in more than two billion people world-wide. In a new theory, Obesity Dyshomeostasis is associated with a 'Circle of Discontent', a system of feedback loops connecting weight gain, body dissatisfaction, negative affect and over-consumption. The Circle of Discontent is consistent with an extensive evidence-base. Obesity Dyshomeostasis occurs when homeostatic control of eating is overridden by hedonic reward. Appetitive hedonic reward is a natural response to an obesogenic environment containing endemic stress and easily accessible, high-energy foods and beverages. The objectives of this book are: (i) To define, describe and discuss the concepts of psychological homeostasis and dyshomeostasis and their relevance to overweight, obesity, the addictions and chronic stress; (ii) To propose a General Theory of Well-Being founded on the construct of psychological homeostasis; (iii) Within the general theory, to specify the Obesity Dyshomeostasis Theory (ODT) of overweight and obesity; (iv) To summarize the body of evidence that is supportive of the general
theory and the ODT; (v) To describe interventions for preventing overweight and obesity based on the ODT. Obesity dyshomeostasis is mediated by the prefrontal cortex, amygdala and HPA axis with ghrelin providing the signalling for feeding dyshomeostasis, affect control and hedonic reward. Dyshomeostasis plays a causal role in obesity, the addictions and chronic conditions and is fueled by negative affect and chronic stress. Prevention and treatment efforts that target dyshomeostasis provide strategies for reducing adiposity, ameliorating the health impacts of addiction, and raising the quality of life in people suffering from chronic conditions and stress. A four-armed strategy to halt the obesity epidemic consists of eliminating the causes of overweight and obesity: (1) Resisting and putting a stop to a culture of victim-blaming, stigma and discrimination; (2) Resisting and devalorizing the thin-ideal; (3) Resisting and reducing consumption of energy-dense, low nutrient foods and drinks; (4) Improving access to plant-based diets. If fully implemented, these interventions should be competent to restore the conditions for homeostasis in billions of people and the obesity epidemic could be halted.
List of Abbreviations BMI: Body Mass Index COD: Circle of Discontent CODT: Circle of Discontent Theory CRF: corticotropin-releasing factor EBT: Energy Balance Theory ED: eating disorder EWCB: extreme weight-control behaviour F/V: fruit and vegetable GH: ghrelin GTW: General Theory of Well-Being HPA axis: hypothalamo-pituitary-adrenal axis nAChRs: nicotinic acetylcholine receptors OD: Obesity Dyshomeostasis ODT:Obesity Dyshomeostasis Theory PFC: prefrontal cortex PLWO: people living with overweight or obesity RCT: randomised controlled trial SDT: Self-Determination Theory UCT: Unhealthy Commodities Tax WIC: Special Supplemental Nutrition Program for Women, Infants, and Children
One: Obesity Since the time of Hippocrates, the dictum of a good diet, exercise, a proper night’s sleep has been a prescription for a healthy life. Illness prevention has been a popular idea ever since. The first president of the American Public Health Association stated in 1874: "...the customs of society must be so changed that the physician is employed to prevent rather than cure disease" (Smith, 1874). Many editorials have addressed obesity, dieting, weight control, and related issues (e.g. Gold & Graham, 2011; Yanovski, 2011; Pagadala & McCullough, 2012; ThePLOS Medicine Editors, 2012; Edmonds & Templeton, 2013; Stuckler & Basu, 2013; Drewnowski, 2014; Fitzgerald, 2014;
Ndisang,
Vannacci & Rastogi, 2014; Potenza, 2014; Sniehotta, Simpson & Greaves, 2014). The obesity epidemic rolls on, unabated. Today the obesity epidemic is 'Public Health Enemy Number One'. Globally, between 1980 and 2013, the prevalence of overweight and obesity rose by 27.5% for adults and 47.1% for children. The number of people living with overweight and obesity (PLWO) increased from 921 million in 1980 to 2.1 billion in 2013 (Ng et al., 2014). A recent collaborative international study included more than 19·2 million adult participants (9·9 million men and 9·3 million women) in 186 of 200 countries for which estimates were made
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(NCD Risk Factor Collaboration, 2016). Global age-standardised mean BMI was found to have increased from 21·7 kg/m2 (95% credible interval 21·3–22·1) in 1975 to 24·2 kg/m2 (24·0–24·4) in 2014 in men, and from 22·1 kg/m2 (21·7–22·5) in 1975 to 24·4 kg/m2 (24·2–24·6) in 2014 in women. According to Dobbs et al. (2014) obesity is responsible for around 5 percent of global deaths and the global economic impact is $2.0 trillion, or 2.8 percent of global GDP, roughly equivalent to the impact from smoking or armed violence, war, and terrorism. In the US in 2004, direct and indirect health costs associated with obesity were $98 billion (CDC, 2013). Depending on the source, it is reported that the direct medical cost of overweight and obesity combined is 5 to10% of US health care spending (Tsai, Williamson & Glick, 2010). Forty-two million children under the age of 5 were overweight or obese in 2013. Prevalence of overweight or obesity in adults doubled from 6% in 1980 to 12% in 2008 (Stevens et al., 2012). By 2050, it is predicted that obesity will affect 60% of adult men, 50% of adult women and 25% of children making the US, Britain, and much of Europe a mainly obese society (Figure 1. Reproduced by permission). The World Health Organisation estimates that around 3.4 million adults die each year as a result of overweight or obesity (WHO, 2014). The WHO (2013) plans to halt the rise in diabetes and obesity by creating a world that is “free of the avoidable burden of non-communicable diseases.” WHO interventions revolve around “mobilizing sustained resources…in coordination with the relevant organizations and ministries” that consist of high
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level meetings between governmental representatives and publication of position statements. Leading authorities have concluded that obesity is a normal response rather than a pathological condition: “...obesity is the result of people responding normally to the obesogenic environments they find themselves in. Support for individuals to counteract obesogenic environments will continue to be important, but the priority should be for policies to reverse the obesogenic nature of these environments� (Swinburn et al., 2011, p. 804). It has been observed that the food and beverage industry ('Big
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Food') does not much care about the health of consumers. Big Food cares about big consumption of cheap food that leads to big profits (The PLOS Medicine Editors, 2012). The lack of effective interventions to date suggests that civil governments have been impotent to stem the tide of health detriments created by the food and beverage industry. The obesity epidemic is of comparable importance to the smoking epidemic. Arguably, obesity will prove to be even more significant in the history of human suffering than smoking. It took 50 years of consolidated pressure to reduce the prevalence of smoking-related diseases. There is enough scientific knowledge now to tackle the obesity epidemic. That systems of governance are market-led with health policies compromised by the interests of multinational industries means that food policy and regulation are not based on scientific evidence but on economic imperatives. There can be little doubt that if the food chain could be rationally developed, and resources were targeted to the most significant causal links of obesity, the epidemic could be solved within a decade from now. The prospects of a properly targeted approach to prevention would be very exciting. All conditions of health and illness are regulated by homeostasis. In this book, I present a new theory of obesity that I call the 'Obesity Dyshomeostasis Theory' and explain its relevance to the worldwide obesity epidemic. 'Dyshomeostis' may seem a bit of a mouthfull, in more senses than one, but its meaning becomes clear as we shall explain the ideas behind the theory. The epidemic is driven by contemporary social, economic and
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environmental conditions that actively create a vicious 'Circle of Discontent' that is difficult for individuals to control. The neurobiological foundations of Obesity Dyshomeostasis Theory (ODT) present interesting possibilities for new therapeutic targets and prevention strategies. Because the ODT receives strong empirical support and explains all of the principle features of the epidemic, it has the potential to enable the epidemic to be halted. Until now, the accepted explanation of overweight and obesity has been the “Energy Balance Theory� (EBT) in which weight gain is a consequence of energy expenditure being less than energy intake. This mechanistic approach has led to a modern obsession with calorie counting and dieting (Marks et al., 2015). It is true that short-term weight loss can be achieved by any calorie-reducing diet but, in the long-term, studies show that calorie-counting is not associated with significant weight loss. One reason for this outcome is that all calories are not equal (Feinman and Fine, 2004). If you eat an equal number of calories of protein, fat and carbohydrates, the metabolic processes are different and calories from fat are more likely to end up on your waist as fewer calories are burned by the thermic effect of eating. The quality and type of foods one consumes influences diverse pathways related to weight homeostasis, such as brain reward, glucose-insulin responses, adipocyte function, metabolic expenditure, satiety, hunger and the microbiome. All calories are not equal: some foods impair pathways of weight homeostasis and others promote the integrity of weight regulation. Associated with the EBT is the view that obesity and overweight
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are the consequences of inactivity. This belief has been responsible for much disillusionment among people striving for significant weight-loss. A 100-kg man needs to run about 20 km. each week to reach a weight of 85 kg. However, this outcome would take approximately 5 years using exercise alone. That would mean running 5000 km., one-eighth of the circumference of the planet, over 5 years to lose 15 kg (Marks et al., 2015). It is perhaps unsurprising that systematic reviewers have concluded that adding physical activity to a dietary intervention for obese individuals has a marginal, if any, effect on average weight loss (Loveman et al., 2011; Swedish Council on Health Technology Assessment, 2013). The inability of EBT to yield effective long-term interventions for obesity treatment and prevention, suggests that the energy balance approach is theoretically inert. It is a purely descriptive theory of energy transfers in and out of the body but it fails to predictive why any particular individual will develop obesity rather than another. The energy balance theory falls short, not only in explanatory power, but because it has done actual harm by stigmatizing overweight individuals who are blamed for being 'greedy' and 'lazy'.
In sum, the EBT is an oversimplified,
descriptive approach that has promoted victim-blaming and stigmatization but done nothing to reduce obesity prevalence (Marks et al., 2015; Marks, 2015a). One might even say that the EBT helped to increase the epidemic. The EBT has out-lived its usefulness and should be retired. Enter dyshomeostasis theory. Dyshomeostasis Theory
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proposes that homeostatic control of eating becomes disrupted under the conditions of modern living in which large sectors of the population are exposed to chronic stress while simultaneously being offered supplies of low-cost fatty and sugary foods. Under such oppressive conditions, palliation of stress and negative affect is facilitated by the hedonic eating of high-energy, high-fat or highsugar foods and beverages, indubitably the main cause of obesity. Over a protracted period of time, OD has a progressively deleterious impact on human physical and mental health and is associated with metabolic syndrome, insulin resistance/diabetes, cardiovascular disease, cancers, fatty liver disease, polycystic ovarian disease, depression and many other conditions that are not easily reversed, or are irreversible. The Food Chain The world is full of contradictions, inconsistencies and inequities (Marks, 2015a,b). On the one hand the Food and Agriculture Organization of the United Nations (2014) reported that 805 million people are chronically undernourished. Yet, the volume of food produced is more than one and a half times what is needed to provide everybody on the planet with a nutritious diet (Weis, 2007). It's not about lack, it's about inequity. While 805 million starve, 2.1 billion are overweight or obese, and that number is increasing. Production and distribution of food and beverages have changed profoundly with globalization. The main driver of the obesity epidemic and that of the other major noncommunicable diseases is unregulated marketing of unhealthy foods and
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beverages. Stuckler et al. (2012) observed that the sales of unhealthy commodities across 80 low- and middle-income countries are strongly interrelated. Moodie et al. (2013) argued that the alcohol and ultra-processed food and drink industries are using similar strategies to the tobacco industry to undermine effective public health policies and programmes.This trend is aided and abetted with commodification of animals in factory farms all over the world. Animals in factory farms live in cruel and harsh conditions that are regarded as efficient and profitable and, as long as consumers are given their fill of cheap beef, mutton, chicken, pork, and salmon, there will be no halting of industrial farming of animals. Indeed, the industry is expanding (Foer, 2009). In Western populations, the majority of people eat meat on a regular basis, products from an industry that requires excessive amounts of energy and leaves a deep carbon footprint. In the US a typical meat eater consumes around 200 animals/part-animals a year or 16,000 over a lifetime (Mohr, 2012). To provide all of this livestock, the agricultural and aquacultural systems degrade land and water, biodiversity and climate both directly through pasture and indirectly through its use of feed and forage, and the methane expelled by cattle (Foley et al., 2011). Ruminants use 86% of the world’s agricultural land and consume 71% of its total biomass, yet produce only 8% of its food (Smith et al., 2013). Human consumption of meat and dairy products is a major driver of climate change. Greenhouse gas emissions associated with their production are estimated to account for over 14.5 per cent of the global total, more than the emissions produced from all the world’s
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road vehicles, trains, ships and aeroplanes combined (Bailey, Froggatt and Wellesley, 2014). The food industry is playing a large part in the destruction of the planet and in causing ill-health across large sectors of its inhabitants. The relentless production of ever increasing amounts of high-energy, processed foods is doing more to destroy human health than any other industrial factor. 'Big Food', 'Big Meat' and 'Big Dairy' pose major health threats with increased prevalence of obesity, diabetes, metabolic syndrome, cardiovascular diseases and cancers everywhere (The PLOS Medicine Editors, 2012). Strong evidence and warnings by experts in nutrition and epidemiology go largely unheeded. The dead hand of governance gathers and reports statistics, but does little to abate the epidemic, while giving every possible assistance to Big Food, Big Meat and Big Dairy (The PLOS Medicine Editors, 2012). This negligence is in spite of five interesting facts: 1) “Red meat consumption is associated with an increased risk of total, CVD, and cancer mortality” (Pan et al., 2012, p. 555). 2) High consumption of red meat is associated with higher circulating levels of gamma-glutamyl transferase (GGT; a biomarker of metabolic syndrome and obesity) and high-sensitivity C-reactive protein (hs-CRP; a biomarker of inflammation and cardiovascular disease) (Montonen, 2013). 3) The intake of high-fat dairy products is associated with an increased risk of CVD mortality (van Aerde, 2013). 4) “Substitution of other healthy protein sources for red meat is associated with a lower mortality risk” (Pan et al., 2012, p. 555).
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5) High consumption of whole-grain bread is related to lower levels of GGT, hs-CRP, and alanine aminotransferase (ALT; a biomarker of liver disease) (Montonen, 2013). Obesity and the Stress of Life An important clue to obesity causation is the fact that economically worse-off people are the greatest consumers of unhealthy foods, while the better-off can afford healthier food and are less prone to overweight and obesity. Drewnowski and others have demonstrated a strong relationship between affordability of food and beverages and their energy density measured in terms of fat and sugar (Drewnowski & Specter, 2004). Energy-dense diets are associated with lower daily food consumption costs and provide an effective way to save money (Drewnowski & Darmon, 2005). On this basis, it is a reasonable assumption that: “Good taste, high convenience, and the low cost of energy-dense foods, in conjunction with large portions and low satiating power, may be the principal reasons for overeating and weight gain” (Drewnowski & Darmon, 2005, p. 900). A systematic review of 27 studies across 10 countries showed that a healthful diet costs $550 per year more than an unhealthy one (Rao, Afshin, Singh, & Mozaffarian, 2013). In England, another study suggested that the healthiest dietary pattern costs double the price of the least healthy, costing £6.63/day and £3.29/day, respectively (Morris, Hulme, Clarke, Edwards & Cade, 2014). To illustrate the general trend, the inverse relationship between economic deprivation and obesity prevalence among
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children in the UK is shown Figure 2. The obesity gradient shows that the rising incidence of overweight and obesity is not just a health issue, it is about social justice.
This fact is reinforced by
evidence that obesity prevalence varies according to ethnic group, education and gender. For example, in the US, non-Hispanic blacks have the greatest prevalence of obesity (35.7%), followed by Hispanics (28.7%) and non-Hispanic whites (23.7%), a pattern that is consistent across all census regions and greater among women than men (Pan et al., 2009). Black American women show heightened rates of obesity over the life course. Research findings suggest that overeating is an effective, early, well-learned response to chronic environmental stressors that
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strengthens over the life course (Jackson et al., 2010). For different social and cultural reasons, Black American men’s trajectories differ from those of Black women’s. Early in life, Black men tend to lead active, athletic lives, but in middle age this dopamine-producing coping strategy is reduced because of physical deterioration. At middle age Black men show increased rates of smoking, alcohol consumption, and illicit drug use. However, Black men do not show high prevalence rates of obesity at any age. This process is not assumed to be inherently linked to racial group membership. The negative outcomes observed among the Black population, in large part, can be attributed to the disproportionate distribution among Blacks of chronic, negative environmental, social, and psychological stressors, as well as the greater availability of environmental sources of unhealthy behaviors. White Americans who lived under similar situations and facilitating structures would almost certainly demonstrate the same processes and outcomes that are observed among the Black American population (Jackson et al., 2010). The relationship between educational achievement and obesity prevalence differs between rich and poor countries. The relationship is modified by both gender and the country's economic development level: an inverse association is more common in higher-income countries and a positive association is more common in lower-income countries, with stronger social patterning among women (Cohen, Rai, Rehkopf and Abrams, 2013). Hans Selye's book, The Stress of Life, first published in 1956, was a significant step in defining how the body responds to long-
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lasting but difficult-to-change problems of living. Throughout this book, I follow Selye in applying the term 'stress' to the body's response to problems of living. When problems of living persist over long periods, such as poverty or unemployment, then it is correct to refer to the resulting condition as 'chronic stress'. Selye (1984) himself stated: “...excessive obesity may also be a manifestation of stress, especially in people with certain types of frustrating mental experiences” (p.265). Selye could not have appreciated how prophetic this statement would be. If “certain types of frustrating mental experiences” can be allowed to include poverty, depression, and body dissatisfaction, then Selye's statement provided a 1950s version of the theory described herein. The purpose of this book is to explain the theory in as much detail as possible.
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Two: Dyshomeostasis In applying a biopsychosocial approach to the understanding of obesity, it is recognized that a complex array of genetic, nutritional, developmental, and environmental factors influence the development of overweight and obesity. However, none seems to ‘tell the whole story’ because, as experts all agree, obesity has multiple causes. Controlled twin study methods suggest that human body size is under substantial genetic control (Stunkard, Foch & Hrubec, 1986). It can be estimated that approximately 50% of the variance in obesity risk is explained by environmental factors and 50% by genetic factors (Bouchard, 1996). It remains necessary to explain how or why overweight or obesity can develop in a susceptible individual, and why some individuals develop it and not others. This is where the CODT surpasses EBT: the CODT not only describes what happens, it explains why it happens, and predicts who will and who won't develop obesity. The potential for complexity has never been more vividly displayed than in the Foresight Report (2007) that referred to a “complex web of societal and biological factors that have, in recent decades, exposed our inherent human vulnerability to weight gain”. The report presented an obesity map with energy balance at its centre and over 100 variables said to be directly or indirectly
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influencing energy balance. The Foresight committee recommended change at many levels—personal, family, environmental and national. The complexity of working with 100 or more variables is daunting and to a degree, paralyzing, as there are so many different avenues and choice points, there is confusion about where exactly one should intervene for change. It isn't really viable to work with 100 variables. One needs a more heuristic approach that can be worked with in practical terms. To be useful in the real world, it is necessary to have a scientific theory of obesity causation that contains a relatively small number of explanatory variables. Sharpening the focus on such a theory enables the planning of systematic interventions to focus on changing health outcomes on a mass scale. Two fundamental questions are: (1) Is the construction of such a theory feasible? (2) Which variables would be the operative ones? Review of the extensive literature from five decades of intensive investigation suggests three primary candidates in causation of overweight and obesity: (i) negative public perceptions of large body size and the resulting high levels of felt dissatisfaction among people with increasingly large body size; (ii) the high levels of negative affect in the form of anxiety, depression and stress consequential upon increasing body size;
(iii) the emotional consumption of fatty
and/or sugary foods and beverages including alcohol. The evidence to be reviewed suggests the existence of strong links between these three key processes. The evidence suggests that the three processes form a feedback system, “The Circle of Discontent�, a circle that arguably
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goes some considerable distance towards explaining the everrising incidence of overweight and obesity (Marks, 2015a). These three processes are well known within the field of obesity research and their interrelationships have been widely researched in thousands of studies. However, the intimate relationship that exists between them in the form of interconnecting, reciprocal feedback loops, and their homeostatic significance have not previously been described. The evidence suggests that Circle of Discontent Theory (CODT) rests on a bedrock of established principles and is buttressed by solid empirical evidence. Moreover, the theory yields testable predictions and provides the foundations for strategies for preventing the further growth of the obesity epidemic. Homeostasis as a Unifying Principle Homeostatic regulation is a singular unifying principle in all health protection and illness prevention. Health is regulated by homeostasis, one of the distinguishing features of all living things; it preserves life when in balance; it disrupts life when imbalanced; when not present at all, a system cannot be living (Mamontov, 2006). Homeostasis operates at all levels of living systems: in cells, tissues, organs, organisms, societies, and, arguably, in biodiversity itself and in the planet as a whole (the Gaia hypothesis; Lovelock, 2009).
Tissue homeostasis regulates the
birth (mitosis) and death of cells (apoptosis); many diseases are directly attributable to defective homeostasis leading to over- or under-production of new cells relative to cell deletion (Fadeel & Orrenius, 2005). Biochemical and physiological feedback loops
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regulate billions of cells and thousands of compounds and reactions in the human body to maintain body temperature, metabolism, blood pH, fluid levels, blood glucose and insulin concentrations inside the body (Matthews et al., 1985). A body in good physical health is in biochemical and physiological homeostasis. Severe disruptions of homeostasis that, if left unresolved, cause illnesses that can be fatal. Homeostasis is the in-built tendency of a living organism to maintain stable equilibrium among its internal components while interacting with an ever-changing external environment. 'Homeorhesis' is the tendency of living organisms to evolve along a trajectory while environmental conditions are continuously changing (Mamontov, 2007). Homeorhesis brings stability, order and normalcy in an evolving trajectory with internal and external disturbances. Homeorhesis is a necessary feature of any living system. If a system does not perform homeorhesis, it is nonliving (Mamontov, 2006). At any particular moment of time, homeorhesis reduces to homeostasis and, in this book, I prefer to use the term “homeostasis” as it is much better known. Hippocrates viewed health as a harmonious balance of elements, and illness as a systematic disharmony of these elements. Galen (CE 129 - 200), the early Roman physician, followed the Hippocratic tradition with hygieia (health) or euexia (soundness) as a balance between four bodily humors, black bile, yellow bile, phlegm, and blood. Galen believed that the body’s ‘constitution’, ‘temperament’ or ‘state’ could be put out of equilibrium by excessive heat, cold, dryness or wetness. Such
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imbalances could be caused by fatigue, insomnia, distress, anxiety, or by food residues resulting from eating the wrong quantity or quality of food. These early ideas about balance and harmony were the foundation of biochemistry, physiology, psychology and medicine in the 19th and 20th centuries. A person in good health is in a state of homeostasis that operates across all systems of biochemical, physiological, psychological and social homeostasis. Outward and inward stability in a life form is only possible by constant adaptation. All living beings strive to maintain a state of equilibrium and stability with other beings and the surrounding environment through millions of micro-adjustments and adaptations to the continuously changing circumstances. Adjustments and adaptations can be both conscious and unconscious. The majority of fine adjustments are occurring at an unconscious level, hidden from both external observers and the individual actor. Physiological Homeostasis In the 1850s Claude Bernard described the milieu intĂŠrieur (the environment within): “The fixity of the milieu supposes a perfection of the organism such that the external variations are at each instant compensated for and equilibrated.... All of the vital mechanisms, however varied they may be, have always one goal, to maintain the uniformity of the conditions of life in the internal environment.... The stability of the internal environment is the condition for the free and independent
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life.” (Bernard, 1974). Following Bernard and others, Walter Bradford Cannon, chairman of the Department of Physiology at Harvard Medical School, took up the concept and named it “homeostasis”. Walter Cannon (1929) described physiological homeostasis and, in so doing, acknowledged the views of Hippocrates and Bernard. Two other people who influenced Cannon's were Pflüger (1877) and Fredericq (1885), who suggested: “The living being is an agency of such sort that each disturbing influence induces by itself the calling forth of compensatory activity to neutralize or repair the disturbance. The higher in the scale of living things, the more numerous, the more perfect and the more complicated do these regulatory agencies become. They tend to free the organism completely from the unfavourable influences and changes occurring in the environment.” In 1932 Cannon defined “homeostasis” as follows: “The coordinated physiological processes which maintain most of the steady states in the organism are so complex and so peculiar to living beings - involving, as they may, the brain and nerves, the heart, lungs, kidneys and spleen, all working cooperatively - that I have suggested a special designation for these states, homeostasis. The word does not imply something set and immobile, a stagnation. It means a condition - a condition which may vary, but which is relatively constant.” (Cannon, 1932, p. 24). Cannon popularized the concept of homeostasis in his best-
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selling book, The Wisdom of the Body (Cannon, 1932). Physiological homeostasis restores the balance in any physiological system that evidences an imbalance. One of the most illustrated examples of is the body's response to excessive heat (Figure 3). There are literally thousands of homeostatic mechanisms at a physiological level that kick in automatically without any conscious awareness of what is happening. One of the most important examples is sleep that provides essential restoration from exhaustion and fatigue. In all forms of illness, homeostasis is disturbed and not properly restored, a state of 'dyshomeostasis'. However, with appropriate treatment, whether pharmacological, hormonal, surgical, or behavioural, there is rehabilitation and recovery. Psychological Homeostasis In parallel with physiological homeostasis are systems of regulation and control of immense sophistication and complexity geared to maintain psychological equilibrium and stability as a person interacts with, and is affected by, the ever-changing external world. In similar fashion to its physiological counterpart, psychological homeostasis regulates action, thought, motivation, and emotion. Continuous activity of feedback loops operate to maintain psychological equilibrium from moment to moment. Psychological homeostasis occurs in response to the infinite variety of circumstances that can affect well-being, including both internal adjustments (e.g. emotional regulation) and external adjustments using deliberate behavioural regulation (e.g. working
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communicating, eating and drinking). Psychological homeostasis operates throughout waking life, whether consciously or not. For most people, most of the time, homeostasis is maintained by thousands of largely invisible, unconscious micro-adjustments and accommodations to behaviour in response to the social and physical surroundings. These microadjustments are controlled centrally by cortical and neurological systems that regulate action, feeling and emotion including response to motivational states such as hunger, thirst, fatigue, cravings and sexual impulses. Psychological and behavioural control are often used to rebalance physiological homeostasis. In diabetic control an individual learns to monitor and maintain blood glucose levels as close to normal as possible, around 70–130 mg/dl before a meal and below 180 mg/dl one to two hours after a meal (American Diabetes Association, 2014). If a diabetic person is to avoid serious complications, then maintaining diabetic control is critical for long-term health. To maintain control, the individual must check their blood glucose levels several times daily and a physician should conduct the A1c test two to four times a year to assess average blood glucose control over the previous two to three months by measuring the level of glycated haemoglobin (HbA1c) in the blood stream. Individuals are commonly advised by their physicians to modify their routines of daily living, especially their diets, working habits, and sleeping patterns to reduce depression, fatigue and stress.
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Other examples of self-monitoring include anticoagulant management with drugs such as warfarin or rivaroxaban and blood-pressure self-management. Behavioural self-monitoring of food and drink consumption (Boutelle & Kirschenbaum, 1998), regular self-weighing to evaluate weight loss (Burke, Wang & Sevick, 2011), the counting of cigarettes consumed in smoking control (McFall, 1970) and self-monitoring of physical activity with pedometers (Bravata et al., 2007) are all behavioural techniques for restoring homeostasis. Behavioural homeostasis works best when guided with a planned series of goals that can help to regulate action (Locke & Latham, 2002). Goal setting is an ideal strategy in stroke rehabilitation (Rosewilliam, Roskell & Pandyan, 2011), cardiac rehabilitation (Moore & Kramer, 1996) and physical therapy (Baker, Marshak, Rice & Zimmerman, 2001). In rehabilitation, better outcomes and higher patient satisfaction are achieved when the patient can set their own goals. In psychological homeostasis, the level of well-being at which the person feels comfortable is a well-balanced arrangement of living or working conditions, with no particular irksome feelings, and without the necessity to regulate consumption of food and drink. In this state, the individual eats and drinks freely without restraint. However, in illness a person feels something is wrong, a growing dissatisfaction with his or her condition, and they feel a sense of alarm, negative affect, sad, lonely, anxious, empty or stressed. One response to disequilibrium is to eat and drink carefully and to take other restorative or conservative steps such as resting or 'taking things quietly' for a while' in order to return to
25
well-being. In many cases, such disequilibrium is episodic and short-lived (Figure 4). Social Homeostasis Another omnipresent system, that of social homeostasis, serves an essential regulatory function in all forms of social action including political and economic behaviour. William Shakespeare, i n As You Like It, refers to the world as a stage and men and women as merely players. The players on the stage are not free to act with hedonistic or libidinous abandon, however. There is a narrative, a script that plots what can happen, and the consequences that will follow. Anarchy is, by and large, avoided. To avoid anarchy, social behaviour involves both explicit and implicit set-points and standards that are variously referred to as 'codes of conduct', 'norms', 'etiquette' or 'manners' all designed to provide acceptable and appropriate forms of social When disruption
or
disturbance
idiomatic terms such as
behaviour.
is perceived, a discourse of
“upsetting the apple cart”, “rocking the
boat”, “making waves”, “causing trouble” and “disturbing the balance” come into play. A narrative of derogatory terms such as 'trouble-maker', 'rabble-rowser', 'hooligan' or 'vagabond' is employed. These sayings make explicit or implicit references to the codes of conduct and politeness, the social forms of balance and homeostasis, that are expected to be employed to maintain social cohesion, equilibrium and harmony. A popular concept is 'self-control'. Loss of self-control is seen as a weakness, and people are told to 'get a grip' or to 'pull
26
themselves together'. In social psychology, a person's sense of self-control is said to be guided by situational cues as to the appropriateness of expressive behaviour and self-presentation, a form of “self-monitoring� (Snyder, 1974, 1987). The social environment in the majority of everyday contexts is maintained in a state that approximates equilibrium through exercise of an infinitude of fine adjustments and accommodations to variously accepted rules of behaviour based on justice, fairness and balance that are designed for an architecture of interaction, conversation, sharing and intimate behaviour towards the common good and shared aims and purposes. Conflicts and confrontations are successfully avoided by accommodations and compromises that are in continuous adjustment to enable fruitful coexistence.
Competing demands
and pressures cause tensions and conflict that require delicate handling and agreed procedures for resolution. Conflict also may be created internally when a person has contrary emotions or desires or it may be external when two or more people seek different means or ends. In conflictual scenarios the smooth operation of central control can breakdown momentarily, for example, in situations of high strain/stress, negative moods, loss of temper, or inappropriate responses to sexual impulses. In the majority of cases the individual returns to a set-point of equilibrium, a point of stability of function, perhaps with compensatory actions such as apologies, compromises, agreements, resolutions, new rules, policies and regulations. If self-regulation fails then institutional means of social control can be deployed using the
27
police force and judiciary. Ideas of social homeostasis and social cohesion were present in Cannon's final chapter of The Wisdom of the Body, first published in 1932.
Here Cannon examined the ‘analogies
between the body physiologic and the body politic’ and suggested that studies of the means by which organisms retained physiological stability in the face of environmental changes might generate new ideas for restoring industrial, domestic and social harmony (Cannon, 1963: 305). Cannon argued that applying the principles of homoeostasis to social organization would not only ‘foster the stability, both physical and mental, of the members of the social organism’, but also provide ‘serenity and leisure, which are the primary conditions for wholesome recreation, for the discovery of a satisfactory and invigorating social milieu, and for the discipline and enjoyment of individual aptitudes’ (Cannon, 1963, p. 324). Selye (1974) followed Cannon in suggesting that parallels could be drawn between physiology and politics: “The same principles must govern cooperation between entire nations: just as a person’s health depends on the harmonious conduct of the organs within his body, so must the relations between individual people, and by extension between the members of families, tribes, and nations, be harmonized by the emotions and impulses of altruistic egotism that automatically ensure peaceful cooperation and remove all motives for revolutions and wars.” (Selye, 1974, p. 64) In a world wracked by wars, terrorism, mass migration,
28
genocide and starvation, Selye's notion of “impulses of altruistic egotism� seem nothing less than naive idealism. An alternative and obverse perspective is that oppressed parties in political and military struggles have no altruistic impulses whatsoever but are aiming single-mindedly to produce maximum amounts of instability and dyshomeostasis as a perfect means of gaining power and control. Integration of Systems It can be seen that the different forms of homeostasis work in parallel in complementary fashion to maximize stability and harmony. In prevention and treatment of clinical conditions, the individual will be advised to monitor and maintain physiological variables using behavioural forms of homeostasis, e.g. in cases of diabetes, metabolic syndrome, hypertension, thyroid problems, skin disorders such as urticaria, or obesity. Biochemical, physiological and psychological homeostasis are of similar complexity.
Behavioural forms of homeostasis occur in actions
designed to support neural systems of regulation. Social homeostasis in supportive actions by other humans or animals, whether requested or simply volunteered, is another way in which the well-being is protected. Other forms of homeostatic control technologies include: (1) electro-mechanical homeostasis, developed by engineers to enhance human control systems such as heating (thermostat), driving (cruise control), navigation (automatic pilot), and space exploration (computer navigation systems); (2) life support systems (e.g. artificial respirators, drip
29
feeding, kidney dialysis, intensive care units) ; (3) medical interventions and surgery; (4) pharmaceutics; (5) alternative and complementary therapies; (6) social, political and economic control. Homeostasis of all kinds operate in mutually supportive and synergistic ways to smooth variability towards a state of equilibrium. Examples of different levels of homeostasis operating in a single scenario are shown in Table 1. The different forms of homeostatic control complement and synergise one another. If one form of regulation fails, another form is activated until the individual, group or population reaches a state of acceptable equilibrium. When there is a perception of injustice, inequality and lack of fairness, there is discontent and unrest, potentially leading to an uprising by those who feel discriminated against, taking action to produce a greater sense of balance and fairness. General Theory of Well-Being In conceptualizing health as an outcome of homeostasis, it is necessary to consider an individual across the lifespan. This lifespan developmental perspective to well-being is encapsulated by the General Theory of Well-Being (GTW; Marks, 2015a; see Figure 5). A lifespan perspective enhances understanding of life transitions such as adolescence and the onset of overweight and obesity. Two processes that have been prominent within the health psychology literature and play a significant formative role are attachment and life satisfaction. These processes will be briefly discussed in turn.
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Attachment Attachment in infancy have been shown to play a profound role in emotional regulation and consequential health-related and developmental behaviours (Bowlby, 1969, 1973, 1980). John Bowlby's well-known Attachment Theory described the infants’ need to maintain proximity to an anchor person who in the most ideal situation is a “secure base” from where to explore the environment. 'Attachment' refers to an enduring affectional bond of substantial intensity (Bowlby, 1969, 1973, 1980). The availability and responsiveness of the anchor person in engaging with the infant's needs creates a template for social interaction. The theory elucidates how experiences with significant others are internalized into mental models of the world and the self, and how these models are generalized to new relationships right through to the individual’s death (Ainsworth, Blehar, Waters & Wall, 1978). Behaviors and strategies that develop and maintain affectional bonds persist throughout life and are activated in order to maintain a desired degree of proximity to highly discriminated persons. According to Bowlby's theory, attachment behavior is protective and facilitates learning. Three primary attachment styles have been distinguished – secure, avoidant, and anxious-ambivalent – and attachment of whichever type can play a role in both childhood and adulthood emotionality (Hazan & Shaver, 1987). Bowlby and Ainsworth both emphasized that attachment experiences in early life involve strong affect across the whole gamut of emotions and feelings including security, anxiety, fear, anger, love, grief and jealousy.
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In Attachment Theory, a model for the whole of life is drawn from processes formed in association with the primary caregiver. The evidence to be reviewed indicates that early parental attachment style plays a critical role in the homeostatic regulation of emotion and in the formation and modification of health-related behaviours such as eating habits (Tabacchi et al., 2007), drinking habits (van der Vorst, Engels, Meeus & Deković, 2006), substance abuse (Schindler, Thomasius, Sack, Gemeinhardt, Kßstner & Eckert, 2005) and romantic love (Brennan & Shaver, 1995). Emotion regulation is a homeostatic process that plays a critical role in the production of ill health, both direct and indirect (Kuh et al., 2003).
DeSteno, Gross and Kubzansky (2013) summarised
evidence that chronic high childhood distress at age 7 or 8 is associated with a range of adult physical health outcomes such as obesity (Goodwin et al., 2009), number of physical illnesses (Kubzansky, Martin, & Buka, 2009) and inflammation (Appleton et al., 2011). Infant feeding requires mother and infant to interact closely and intimately (Schloim et al., 2015) and can influence eating later in life (Nicklaus & Remy, 2013). Parents who bottle-feed may not recognise the infant's signals of hunger or fullness and thus overfeed their infant, potentially reduced the infant's ability to selfregulate when older (Birch, 2006). In breastfeeding the infant can actively regulate the flow of milk from the breast, controlling the pace of the meal and the sense of fullness (Shloim et al., 2015). Long-term effects of early feeding styles have been observed at six years of age such that bottle-fed infants are more likely to be
34
expected to empty their bottles and show lower satiety responsiveness compared to breast-fed infants (Li et al., 2014). Excessive parental control over feeding such as restriction or pressure to eat may be adversely associated with under- or overfeeding respectively, potentially leading to feeding problems (Johnson & Birch, 1994; Farrow & Blissett, 2006). Other studies suggest that lower levels of controlling feeding behaviours promote healthier eating behaviours in childhood (Faith et al., 2004; Birch, Savage & Ventura, 2007; Fisher and Birch, 1999). Childhood dietary habits tend to persist into adulthood, with parental influences that are internalized and enacted in dietary choices throughout the lifespan. Future emotion regulation is set by parental/caregiver patterns of interaction with their children (Mikulincer and Shaver, 2007).Troisi et al. (2005) observed that women with eating disorders reported having more severe symptoms of separation anxiety during chil dhood, and scored higher on a scale assessing insecure styles of adult attachment. Goossens, Braet, Van Durme, DecaluwĂŠ and Bosmans (2012) reported that insecure attachment toward the mother among 8-11 year-olds predicted increases in dietary restraint, eating concerns, weight concerns, and shape concerns, and adjusted BMI in children one year later. Insecure parental attachment, whether actual or recalled has been associated with high calorific food consumption (Faber & DubĂŠ, 2015). Similar findings exist for adult drinking problems and antecedent attachment style (Molnar, Sadava, DeCourville & Perrier, 2010). Thus, attachment patterns in childhood are associated with a
35
variety of homeostatic behaviours throughout life, particularly consumption of food, drink and drugs, and social relationships with romantic partners, family and friends. In any analysis of well-being, the organism's relationship with 'consumption' is a significant determinant of his or her physical and mental well-being. The category of 'consumption' includes not only food, beverages, medicines and substances, but material goods, housing, vehicles, clothing, shoes, fashion accessories, cosmetics, hobbies, computers, mobile phones, tablets, devices, gadgets, sports, golf club membership, holidays, cruises, skiing, gambling, pornography, entertainment, leisure activities and other forms of 'conspicuous consumption', including generation of waste and an individual's carbon footprint. An individual's resources, especially his or her disposable income, the assets in their possession that can be disposed of in any way they choose, and the ability to show restraint, to resist or restrict consumption by design, are the key driver and brake on consumption. Gaining energy through eating and drinking, and using it through activity and mobility provide a feedback loop with the power to stabilize or destabilize well-being. In the majority of cases, overweight and obesity are the consequence of one of both of two processes: (i) a high set-point for adiposity based on genetic predisposition that resists intervention but can be altered by a lifestyle that has high levels of activity (Li et al., 2010); or (ii) gradual dyshomeostasis caused by a disruption in consumption of food and drink owing to increased hedonic reward-based consumption overriding homeostasis.
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Complex social patterns, geared by early parental attachments, also affect life satisfaction, which I discuss next. Life satisfaction How satisfied a person is with his/her life and their level of subjective well-being are key concepts in bringing about homeostatic equilibrium, according to the GTW (Figure 5). According to Diener and Chan (2011), having high life satisfaction adds 4 to 10 years to the lifespan. The life-satisfaction construct is given an operational definition by the method used for its measurement. One prominent scale has been the Satisfaction With Life Scale (SWLS; Diener et al., 1985) that uses a 7-point Likert scale with five items: __In most ways my life is close to my ideal __The conditions of my life are excellent __I am satisfied with my life __So far I have gotten the important things I want in life __If I could live my life over, I would change almost nothing The SWLS provides a hedonic definition of well-being. However, life satisfaction is also about meaningfulness, purpose and self-realization, or the degree to which a person is 'fully functioning' (Ryan & Deci, 2001). Eudaimonic well-being occurs when a person lives in accordance with his/her ‘daimon’ or true self (Waterman, 1993). Eudaimonia occurs when life activities are informed by deeply-held values and are authentic expressions of such values. Empirical studies suggest strong and stable relationships
37
between meaning in life and subjective well-being (Zika & Chamberlain, 1992). People who experience their lives as meaningful are more optimistic and self-actualized (Compton et al., 1996), experience more self-esteem (Steger et al., 2006), more positive affect (King et al., 2006), less depression and anxiety (Steger et al., 2006) and less suicidal ideation (Harlow et al., 1986). The salutogenic theory of Antonovsky (1979) emphasized the relationship between meaning and purpose in life, assessed using the Sense of Coherence scale, and positive health outcomes (Eriksson & LindstrĂśm, 2006). Eudaimonic well-being is similar to the concept of “self-actualizationâ€? espoused by Maslow (1943). To date, the evidence for the protective effects of hedonic well-being on heart health is stronger than for eudaimonic well-being (Boehm & Kubzansky, 2012). When eudaimonic aspects to life satisfaction are combined with hedonic well-being, the association with longevity could be even more robust. Evidence for an association between life satisfaction and all-cause mortality is mounting in several domains suggesting a causal link between life satisfaction, affect, consumption and health. These causal links are specified by the GTW (Figure 5). Considering any population, there is a large group of people who experience a statistically average level of life satisfaction but who are neither satisfied nor dissatisfied with their lives. A range of one-half of one standard deviation on either side of the mean includes 38.2% of the population who can be assumed to be at or close to homeostasis. They are neither content nor discontent. Setpoints may move up and down according to circumstances
38
(Diener, 2000) and adaptation processes occur to help people move towards a position of perceived (by them) well-being even if the objective circumstances are quite dire (Headey & Wearing, 1992). Although a small percentage (<5%) may swing from one extreme to the other, life satisfaction in adults is moderately stable over significant periods of the lifetime (Eid & Diener, 2004; Koivumaa-Honkanen, Kaprio, Honkanen, Viinamäki & Koskenvuo, 2005). Homeostatic imbalance is evident when life satisfaction falls below an equilibrium set-point towards significant dissatisfaction and discontent (30.9% of the population). This state of relatively stable discontent is associated with negative affect and, frequently, over-consumption of unhealthy food and/or drink. The associations become stronger as the dissatisfaction level increases. Among an identifiable section of the population, life dissatisfaction can become persistent and more extreme, placing them at risk of adverse health outcomes (Koivumaa-Honkanen, Kaprio, Honkanen, Viinamäki & Koskenvuo, 2005). A state of extreme dissatisfaction/discontent/disequilibrium over a long period typically is associated with a variety of adverse consequences including depression, anxiety, alcoholism, substance abuse, smoking, gambling, insomnia, accidental injury, inadequate coping and obesity. A few illustrative studies can be summarized here. Newcombe, Bentler and Collins (1986) assessed 640 adolescents and 4 years later as young adults on associations between their alcohol use and dissatisfaction. Cross-lagged latent variable structural models were employed to evaluate the
39
antecedents and consequences of alcohol use on the life satisfaction measures. Alcohol Use and Self-Derogation were positively correlated at the first time point. However adolescent alcohol helped them as young adults to feel better about themselves but increased dissatisfaction levels regarding peer relationships and the environment. Self-reported life satisfaction and mortality were investigated in a prospective study (1976–1995) of 22,461 healthy Finnish adults (Koivumaa-Honkanen, Honkanen, Viinamäki, Heikkilä, Kaprio & Koskenvuo, 2000). Life satisfaction was scored as a threecategory variable yielding the satisfied group (21%), intermediate group (65%), and dissatisfied group (14%). The age-adjusted hazard ratios of all-cause, disease, or injury mortality among dissatisfied versus satisfied men were 2.11, 1.83, and 3.01 respectively. Dissatisfaction was associated with increased disease mortality, particularly in men with heavy alcohol use (hazard ratio = 3.76). In a related study, Koivumaa-Honkanen, Kaprio, Honkanen, Viinamäki and Koskenvuo (2004) investigated the relationship between life satisfaction and depressive symptoms in healthy adults both cross-sectionally and longitudinally with a nationwide sample of healthy adults (N=9679) aged 18–45. Longitudinally, a strongly increased risk of moderate or severe depression in 1990 was observed among those who had been dissatisfied compared with those satisfied in 1975 (OR=6.7) and in 1981 (OR=10.4). Strine et al. (2008) examined associations between life satisfaction and health-related quality of life, chronic illness, and
40
adverse health behaviors among adults. They used the 2005 Behavioral Risk Factor Surveillance System database in which 5.6% of US adults (about 12 million) reported that they were dissatisfied or very dissatisfied with their lives. A strong and consistent relationship existed between life dissatisfaction, negative affect and excessive consumption including smoking, heavy drinking. As the level of life satisfaction decreased, the prevalence of fair or poor general health, disability, and infrequent social support increased as did physical distress, mental distress, activity limitation, depressive symptoms, anxiety symptoms, sleep insufficiency, and pain. The association of alcohol use and alcohol-related problems in several domains of life satisfaction was studied in a sample of 353 students (Murphy, McDevitt-Murphy & Barnett, 2005).
Alcohol-
related problems were associated with decreased life satisfaction among both men and women. In a cross-cultural analysis of 17,246 students from 21 countries, Grant, Wardle and Steptoe (2009) studied the relationship between life satisfaction and seven health behaviors
Grant et al. found that life dissatisfaction was
positively associated with smoking, lack of physical exercise, failure to use sun protection, not eating fruit, and fat intake, but, after adjusting for age, gender, and data clustering, it was unrelated to alcohol consumption or fibre intake. Zullig, Valois, Huebner, Oeltmann and Drane (2001) explored the relationship between perceived global life satisfaction and selected substance use behaviors among 5032 public high school students in the 1997 South Carolina Youth Risk Behavior Survey.
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Cigarette smoking, chewing tobacco, marijuana, cocaine, regular alcohol use, binge drinking, injection drug, and steroid use were significantly associated with reduced life satisfaction. In addition, age of first alcohol drink, first marijuana use, first cocaine use, and first cigarette smoked were all significantly associated with reduced life satisfaction. Kuntsche and Gmel (2004) found that binge drinkers had lower life satisfaction, more depression, and were more often offenders of bullying and hitting. Solitary binge drinkers were found to be the most socially inhibited, prone to depressive symptoms, and victims of bullying in comparison to social binge drinkers who were socially accepted but more likely to be actual offenders of violence (Kuntsche & Gmel, 2004). Brassai, Piko and Steger (2015) explored the role of meaning in physical activity and healthy eating among 456 East-European adolescents. The presence of meaning, search for meaning, subjective well-being and health values at Time 1 were used to predict levels of healthy eating and physical activity 13 months later. All four variables predicted engagement in healthy eating and physical activity; presence of, and search for, meaning were the most robust predictors of healthy eating among boys and physical activity among girls. Conclusions on Homeostasis and Well-Being In adopting a lifespan perspective, the GTW is founded upon the strikingly powerful associations that have been evidenced between attachment style, life satisfaction and health-seeking
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behaviours, particularly those concerning consumption. Hazard ratios for discontented vs. contented samples typically range from 3.0 to 10.0. It is apparent that dissatisfied, distressed, and discontented people eat and drink to excess, assuaging not only their hunger and thirst, but their considerable discontents.
The
implications of these principles for the development of overweight and obesity are illustrated in Figure 6.
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Three: Evidence Obesity is a consequence of a homeostatic imbalance in the psychological sphere. I focus in this chapter on six feedback loops that form an insidious and vicious 'Circle of Discontent' (Figure 7). The theory assumes that, for most people, much of the time, these six pathways are in equilibrium. When so, it is a Circle of Content. However, if, for whatever reason, high levels of dissatisfaction, negative affect, consumption, or increased body weight should arise, then the interactivity through the feedback loops forms a vicious circle, a disturbance to the stability of the system that controls weight gain. Once activated, the system drifts away from equilibrium towards what in effect becomes a dysfunctional state of non-control. This follows from the fact that the activation of any one of the four processes within the circle will activate its neighbours. The feedback loops will run up activity levels throughout the system that will go into overdrive, similar to a badly performing motorcar with the accelerator pedal stuck all the way to the floor. Six pathways link the four processes together in a single system, the 'Circle of Discontent'. The first five of these links have been the subject of extensive research. In the following sections, I
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discuss each of the six pathways in turn, in light of representative studies.
Pathway 1 Reciprocal causal relationships exist between overweight/obesity and body dissatisfaction. â&#x20AC;&#x153;The problem is as inescapable as our image in a mirrorâ&#x20AC;? (Kumanyika, 2007). Many investigators have found an association between overweight or obesity and body dissatisfaction. Presnell et al. (2004) examined risk factors for body dissatisfaction using prospective data from 531 adolescent boys and girls. Elevations in body mass, negative affect, and perceived pressure to be thin from peers, but not thin-ideal internalization, social support deficits, or perceived pressure to be thin from family, dating partners, or
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media, predicted increases in body dissatisfaction. Gender was found to moderate the effect of body mass on body dissatisfaction and also negative affect. McLaren et al. (2003) studied the relationship between past body size and current body dissatisfaction among 933 middle-aged women from a prospective birth cohort study. Women who were dissatisfied at mid-life were found to have been heavier at age 7 and showed a more rapid increase in body mass index with age. Neumark-Sztainer, Paxton, Shannan, Haines and Story (2006) investigated body dissatisfaction in a prospective study with 440 early adolescent girls and 366 boys and 946 mid- adolescent girls and 764 boys. Participants were followed up 5 years later (Time 2). Prospective risk factors included BMI, socioeconomic status, ethnicity, parent dieting environment, peer environment, and psychological factors. Predictors of Time 2 body dissatisfaction were Time 1 body dissatisfaction, BMI, socioeconomic status, being African American, friend dieting and teasing, self-esteem, and depression. However, the profile of predictors differed across the samples. A construct that could be a valuable element in designing interventions is self-compassion with three components: (a) selfkindness—being kind and understanding toward oneself in instances of pain or failure rather than being harshly self-critical, (b) common humanity—perceiving one’s experiences as part of the larger human experience rather than seeing them as separating and isolating, and (c) mindfulness—holding painful thoughts and feelings in balanced awareness rather than over-
47
identifying with them (Neff, 2003, p.85).
In a sample of
undergraduates, Duarte (2015) found BMI to be highly positively associated with body image dissatisfaction (r= .58), in line with pathway 1. A novel finding was that self-compassion buffered the association between negative body image evaluations and young women’s quality of life. An investigation by Cruz-Sáez et al. (2015) of emotional distress and body image concerns in 712 Basque Country, Spanish normal-weight and overweight adolescent girls reported evidence that is fully consistent with the CODT. Cruz-Sáez et al. (2015) found 12.3% of normal-weight girls and 22.5% of overweight girls with extreme weight-control behaviours (EWCBs), i.e., self-induced vomiting, taking laxatives, diuretics, diet pills, and fasting. In normal-weight adolescents, engagement in EWCBs was associated with high levels of somatic symptoms, a drive for thinness and control over eating. In overweight girls, high levels of emotional distress, body dissatisfaction and depression were associated with EWCBs. The Cruz-Sáez et al. (2015) findings are completely consistent with the CODT. Highly significant positive relations were found between BMI, emotional distress, body image concerns and EWCBs, as predicted. EWCBs represent an adolescent's striving to restore a more ideal state of homeostasis, to break the Circle of Discontent by restoring and normalising equilibrium between their body weight, body satisfaction, affect and consumption. In Cruz-Sáez et al.'s study, EWCBs occurred with greater frequency in overweight than in normal-weight adolescents. The overweight adolescent females
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reported a greater drive for thinness, more body dissatisfaction and more negative self-beliefs. In normal-weight females emotional distress, negative self-belief, control over eating, and drive for thinness predicted engagement in EWCB. In overweight girls, GHQ-28 total score, depression, and body dissatisfaction predicted EWCB. These results led the authors to conclude: “emotional distress, excessive importance placed on physical appearance to define oneself, low self-esteem and t he negative cognitions associated with the body and eating, play an important role in the development of weight-control behaviours that put adolescent girls’ health at risk, even those considered normal-weight” (Cruz-Sáez et al., 2015). Further analyses were presented by Cruz-Sáez et al. (2013). Vocks et al. (2007) invited participants with eating disorders (ED) to look at their own bodies in the mirror for 40 minutes and compared their responses to 'normal controls' (NC). The group with ED showed higher negative emotional and cognitive responses to body exposure compared to NC. During the reflected body exposure, the extent of negative emotions and cognitions decreased significantly with medium effects for emotions and low effects for cognitions. Pathway 2 Reciprocal causal relationships exist between body dissatisfaction and negative affect. Several studies have provided evidence consistent with pathway 2 in the CODT. In a prospective study, Rierdan et al. (1989) evaluated the importance of body image in early adolescent
49
girls' depression. Depression scores of over 500 girls were assessed twice, in the fall (Time I) and spring (Time 2) of a school year. Discriminant analyses indicated that body image at Time 1 was important in the prediction of persistence of depression. Paxton et al. (2006) examined whether body dissatisfaction prospectively predicted depressive mood and low self-esteem in adolescent girls and boys 5 years later. Time 1 body dissatisfaction was a unique predictor of Time 2 depressive mood and low self-esteem in early-adolescent girls and mid-adolescent boys. They concluded body dissatisfaction is a risk factor for depressive mood and low self-esteem in both girls and boys but at different phases of adolescence. Mond, Van den Berg, Boutelle, Hannan and Neumark-Sztainer (2011) found that impaired emotional well-being of overweight adolescents is due primarily to the effects of weight-related body dissatisfaction during both early and late adolescence. The authors concluded that body dissatisfaction is â&#x20AC;&#x153;central to the health and well-being of children and adolescents who are overweightâ&#x20AC;?. A reciprocal causal association between depression and body dissatisfaction was also reported by Keel et al. (2001). Participants had completed a controlled treatment study of bulimia nervosa and participated in follow-up assessments 10 years later. Baseline levels of depression were found to prospectively predict body dissatisfaction at follow-up assessment suggesting that depression is a contributing factor in the maintenance of body dissatisfaction over a 10-year period. In a prospective study, Wardle, Waller and Rapoport (2001)
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found that baseline
depression was associated both with body
satisfaction and binge eating and that depression contributed independently to binge eating and partly mediated the bodydissatisfaction effect. This pattern was confirmed in the longitudinal analysis with reduced depression being associated with less binge eating, and reduced depression partly mediated the effect of reduction in body dissatisfaction. Wardle et al. (2001) suggested that: â&#x20AC;&#x153;reductions in depressed mood or improvements in well-being during obesity treatment might be expected to have enduring effects on eating controlâ&#x20AC;? (p. 778). Pregnancy tends to be a period of stress and anxiety, especially if there is an eating issue (Ward, 2008). Clark et al. (2009) examined depression and body dissatisfaction across pregnancy and the first 12 months postpartum. During pregnancy, women's perceived attractiveness and strength/fitness remained stable, while feeling fat and salience of weight/shape decreased in late pregnancy. During the postpartum, feeling fat and salience of weight/shape increased. Depression and body dissatisfaction were correlated concurrently and across multiple time points. Prospective analyses carried out by Clark et al. suggested that greater depression late in pregnancy predicts body dissatisfaction at six weeks postpartum and feeling fat throughout the postpartum. Pathway 3: Reciprocal causal relationships exist between negative affect and consumption of high-density foods and beverages. Reciprocal causal links in the pathway between negative affect
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and consumption of high energy foods are well established in the literature. For example, evidence from qualitative studies such as: “food is like a sedative to me. It knocks me out, like a drug. When I feel any little bit of sadness or anger, I eat. It's almost like being fed as a baby. I will eat and eat until I can't move and then I go and lie down and I sleep. And it's almost like, 'Here baby, come to mother....” or “Eating stops the process of my brain going. It offers relief from thoughts that might actually be quite uncomfortable” (Byrne, Cooper, & Fairburn, 2003). These qualitative findings are borne out by many quantitative studies. People eat to calm themselves, reward themselves, assuage sadness or guilt, or to reduce feelings of isolation. A variety of discontents have been shown to have associations with food consumption including basic need satisfaction (Timmerman & Acton, 2001), anxiety (Nguyen-Rodriguez, Unger, & Spruijt-Metz, 2009; Schneider, Appelhans, Whited, Oleski, & Pagoto, 2010), anger (Macht, 1999), stress (Adam & Eppel, 2007) and boredom (Rocke, 2015). Emotional eating has been viewed as an 'escape' to avoid negative self-awareness resulting in behavioral disinhibition and overeating (Heatherton & Baumeister, 1991). Distress- or discomfort-induced eating, including binge eating, is an available response to negative emotions (Arnow, Kenardy, & Agras, 1995; van Strien & Ouwens, 2007; Stice, 2001; Stice, Presnell, & Spangler, 2002a) as is overeating in vulnerable individuals (van Strien, Engels, Leeuwe, & Snoek, 2005). Some studies suggest that women are more prone to emotional consumption than men (Grunberg, & Straub, 1992; Tanofsky,
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Wilfley, Spurrell, Welch & Brownell, 1997). Men may rely on other outlets such as drinking, drugs and gambling (see below). Le Port et al. (2012) examined the association between dietary patterns and depressive symptoms over 10 years in a French cohort of 12,400 people aged 45â&#x20AC;&#x201C;60 years. Low-fat, Western, snacking and fat-sweet diets in men, and low-fat and snacking diets in women, were associated with depressive symptoms at the start and at follow-up. Conversely, a traditional diet (characterized by fish and fruit consumption) was associated with a lower likelihood of depressive symptoms in women. The healthy pattern, characterized by vegetable consumption, was associated with a much reduced risk of depressive symptoms. The authors suggested that there was probably a reverse causality effect for the healthy pattern. In a longitudinal, population-based study of 2,359 men and 2,791 women in Northern Finland, BMI at 31 years was highest among stress-driven eaters and drinkers, especially among women (Laitinen, Ek & Sovio, 2002). Stress-driven people liked eating sausages, hamburgers and pizza, and chocolate more frequently than other people and consumed more alcohol. Rosenbaum and White (2015) investigated depression, anxiety, and stress as independent correlates of binge eating in a mixed, community sample with diverse backgrounds. The findings indicated a relationship between anxiety and binge eating, and between stress and binge eating, independent of depression. Holt et al. (2015) examined whether there is a relationship between trans fatty acid (TFA) intakes and emotion regulation,
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mediated by positive or negative affect. Archival data on 1699 men and 3293 women were analyzed to measure TFA intake at baseline, positive and negative affect and emotion regulation at follow up. Holt et al. (2015) reported that higher TFA intake was associated with subsequent difficulties with emotional awareness, clarity and regulation strategies, all of these relationships being mediated by affect. Lower TFA intake is associated with increased positive and decreased negative affect which, in turn, are associated with improved emotion regulation. These findings suggest that TFA intakes may cause problems in the regulation of emotion. Rocke (2015) revealed that proneness to boredom and difficulties in emotion regulation simultaneously predict inappropriate eating behavior, including eating in response to boredom, other negative emotions, and external cues. Economic pressures influenced depressive symptoms and also spousal support, which serves as a buffer against poor health and weight management behaviors for husbands, while depressive symptoms exacerbated poor health and weight management behaviors for wives (Oâ&#x20AC;&#x2122;Neal et al., 2015). Economic hardship can also trigger disrupted sleep. Lundahl and Nelson (2015) propose four ways in which sleep problems are likely to increase food intake, namely: homeostatic mechanisms that disrupt appetitive hormones; impaired executive/cognitive functions with corresponding increases in reward sensitivity; increased negative affect and stress; and increased impulsivity. Guertin et al. (2015) tested a longitudinal motivation model for healthy eating in patients with
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cardiovascular disease. Participants with self-determined motivation were found to be more likely to develop a sense of selfefficacy towards eating and a healthy diet that had beneficial effects on their physical health and life satisfaction. Kola-Palmer et al. (2015) reported gender differences and correlates of extreme dieting behaviours (EDBs) among 15,425 US adolescents from the 2011 Youth Risk Behavior Survey. Being hit by a partner, being raped, bullied in school, e-bullied and feelings of hopelessness were all associated with a higher odds ratio for EDBs in both females and males and concluded that: “fasting, diet pill use, and purging may be quick and useful markers (‘red flags’) for other risk behaviours and mental health difficulties for both genders”. EDBs are an indicator of restraint, conscious striving towards homeostasis. Restraint When negative affect can so easily trigger emotional consumption, dietary restraint is used to strive towards a set-point for weight, a conscious form of homeostasis (Figures 5 and 6). The association between restraint, dieting and binge eating has been extensively researched for at least four decades (Herman and Mack, 1975; Polivy & Herman, 1985). Dietary restraint involves a conscious effort to eat according to cognitive cues rather than physiological cues such as hunger or satiety in order to lose or maintain weight (Herman and Mack, 1975). Herman and Mack (1975) presented sequence data indicating that dieting usually precedes binge eating chronologically. Evidence suggests that distress suppresses eating in non-dieters (unrestrained eaters),
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but increases it in chronic dieters (restrained eaters) (e.g. Baucom & Aiken, 1981). Polivy and Herman (1999) investigated the â&#x20AC;&#x153;masking hypothesisâ&#x20AC;? that dieters use overeating to mask distress in other areas of their lives by eating when distressed so they can attribute their distress to their overeating rather than to more uncontrollable aspects of themselves or their lives. Other hypotheses include the idea that eating acts as a distraction from negative affect or that eating is a form of learned helplessness. Polivy and Herman (1999) led female college participants to believe that they had failed or not failed a cognitive test and then gave them either ad libitum or three small spoonfuls of ice cream to taste and rate. They indicated that the masking, distraction, and helplessness hypotheses all received some support and that they may work in tandem with each other. Polivy and Herman's results suggested that distress-induced overeating in restrained eaters may serve psychological functions for the individual, allowing distraction from the distress or masking of the source of dysphoria. Restraint also can create a rebound effect as binge eating. Marcus, Wing and Lamparski (1985) determined the prevalence and severity of binge eating among 432 women. 46% of the women reported serious binge eating, especially younger and heavier women, in whom binge eating severity was related to overall dietary restraint.
Other studies have not confirmed this
finding. In a prospective study, Johnson and Wardle (2005) found no evidence of a rebound of bulimic binge eating among restrainers whereas body dissatisfaction was associated with all
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adverse outcomes, in line with many studies showing a strong association between body dissatisfaction and
depression (e.g.
Paxton, Neumark-Sztainer, Hannan & Eisenberg, 2006). Pathway 4 Reciprocal causal relationships exist between consumption of high-energy foods and overweight or obesity. Many strands of evidence suggest causal links between the consumption of high-caloric foods containing high levels of fat and/or sugar and the development of obesity. A review of clinical trials with humans that studied the effects of a reduction in the amount of energy from dietary fat showed that a reduction of 10% in the proportion of energy from fat was associated with a reduction in weight of 16 grams per day (Bray & Popkin, 1998). A more recent review came to similar conclusions (Hooper et al. 2012) suggesting a causal link between ingested fat and weight change. Passive overconsumption of high-fat foods, in particular, has been linked with a higher frequency of obesity (Blundell & MacDiarmid, 1997). In a prospective study with 107,243 postmenopausal American women aged 50-79 years, greater chocolate-candy intake was associated with greater prospective weight gain (Greenberg et al., 2015). Increased usage of sugar-sweetened beverages has been found to cause weight gain and incidence of type 2 diabetes in young and middle-aged women (Schulze et al., 2004). Systematic review
of prospective cohort studies and RCTs by Malik et al.
(2013) showed evidence that consumption of sugar-sweetened beverages promotes weight gain in children and adults
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Economic analyses suggested that the increased prevalence of obesity in the US can be largely attributed to the increased frequency of snacking in the diet (Cutler, Glaeser & Shapiro, 2003; Jahns, Siega-Riz & Popkin, 2001). McDonald, Baylin, Arsenault, Mora-Plazas and Villamor (2009) investigated the prevalence of overweight and any associations with dietary patterns and physical activity in a prospective study in children in BogotĂĄ, Colombia. Overweight was 3.6 times greater in children whose mothers were obese compared with children whose mothers had adequate BMI. Child overweight was also positively associated with adherence to a â&#x20AC;&#x153;snackingâ&#x20AC;? dietary pattern and to frequent intake of hamburgers and hot dogs with a prevalence ratio for at least once per week vs. never of 1.93, independent of total energy intake and other potential confounders. In a second report, a snacking dietary pattern and soda intake were both found to be related to the development of adiposity (Shroff et al., 2014). Snacking and eating during the night is more apparent in people suffering from psychological distress (Colles, Dixon and O'Brien, 2007) and depression, and is a risk factor for obesity (Gallant, Lundgren & Drapeau, 2012). Pathway 5 Reciprocal causal relationships exist between obesity and negative affect. Setting aside the fact that weight gain is an unwanted side effect of some drug treatments for psychiatric disorders (Zimmerman, Kraus, Himmerich, Sckuld & Pollmacher, 2003), psychiatric studies indicate a reliable association between
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depression and obesity. This association has been observed in both cross-sectional and prospective studies. Onyike et al. (2003) studied rates of depression for both men and women as a function of BMI. The participants were 9,997 respondents to the National Health and Nutrition Examination Survey (NHANES), an interview survey of the US population. Obesity was associated with increased rates of depression. A prospective study of depression and adolescent obesity with 9374 participants by Goodman and Whitaker (2002) showed that depressed mood at baseline independently predicted obesity at follow-up (odds ratio: 2.05). Depressed mood at baseline also predicted obesity at follow-up among those not obese at baseline (odds ratio: 2.05). Werrij, Mulkens, Hospers and Jansen (2006) investigated whether depressive symptoms in people with overweight or obesity is related to increased eating problems and decreased self-esteem. Depressed participants were observed to suffer from more eating problems, more restraint and higher BMI than non-depressed participants. Roberts et al. (2003) examined the temporal association between obesity and depression in a two-wave, 5-year observational study with 2123 participants, aged 50 years and older. Obesity at baseline was associated with increased risk of depression five years later, even after controlling for depression at baseline and an array of other covariates. Luppino et al.'s (2010) systematic review of longitudinal studies of depression and obesity indicated that obesity at baseline increased the risk of onset of depression at follow-up by 55% while overweight increased the
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risk of onset of depression by 27%. Similar findings were published by Faith et al. (2011) from a Swedish longitudinal case control study of children from birth to 15 years in which children more than 15% above average weight had suffered more psychosocial stress than controls (Mellbin & Vuille, 1989). In a prospective study of 7965 British civil servants aged 35â&#x20AC;&#x201C;55 at entry into the Whitehall II study, Kivimäki et al. (2006) measured work stress and BMI at baseline and 5-years later. A bidirectional effect of work stress on BMI was evident among overweight and obese men, but weight loss was more likely among stressed lean men. Pathway 6 linking body dissatisfaction directly with consumption. Relatively few studies have investigated the direct association between body dissatisfaction and consumption of food and beverages. Stice and Shaw (2002) reviewed evidence that pressure to be thin, thin-ideal internalization and elevated body mass increased the risk for body dissatisfaction. They found consistent support for body dissatisfaction as a risk factor for eating pathology. However they concluded that this relationship is mediated by increases in dieting and negative affect, in consistency with the CODT. Because findings have been inconsistent, the potential role of the direct pathways between body dissatisfaction and consumption remains uncertain (Figure 7, pathway 6). There is scope here for further investigation, ideally within prospective studies specially designed to evaluate the Circle of Discontent Theory of obesity.
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Variations in Outward Expression of the COD The pattern of findings across the studies reviewed is consistent with the CODT. Previous theories of overweight and obesity have focused on similar features: (i) The Psychosomatic Theory suggested that eating reduces anxiety, and individuals become overweight or obese because they learn to eat in response to emotional arousal or to reduce anxiety rather than in response to internal hunger cues (Bruch, 1961; Kaplan & Kaplan, 1957). (ii) The Spiral Model proposed by Todd Heatherton and Janet Polivy (1992) hypothesized that negative self-evaluations by dieters when confronted with slim body images leads to a spiral of increased negative affect and body dissatisfaction, reduced selfesteem, and increased susceptibility to dietary disinhibition and overeating. (iii) The Stress/Reward Model of Tanya Adam and Elissa Epel (2007) have also proposed that the obesity epidemic is being exacerbated by the prevalence of chronic stress, unsuccessful attempts at food restriction, and the effects on increasing the reward value of high energy food. The three theories, in common with the CODT, share the assumption that eating and drinking are, in part, responses to arousal of negative affect. As a specific case of the General Theory of Well-Being, the CODT can be confirmed or falsified using prospective investigations, qualitative studies, and case reports. The unifying concept extends to the field of psychology a principle that has been established in physiology for at least 150
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years. The 'Circle of Discontent' as a universal phenomenon of the human condition is evident in every population, religious, cultural and ethnic group, but the form of its expression varies according to national, cultural, religious and group-specific preference patterns of consumption. A few illustrative examples follow. In overweight adolescents and women consumption of sugarsweetened beverages is a trend that is associated with weight gain (e.g. Schulze et al., 2004). Large differences exist between different countries in the frequency of use of soft drinks and sweets (Kuusela et al., 1999). For a significant proportion of men, and a smaller proportion of women, alcohol, smoking, cannabis and/or psychotropic drugs is used as a form of 'self-medication' instead of food or prescription drugs when confronted by stress, anger, anxiety or depression (Breslau, Kilbey & Andreski, 1993; Helzer, & Pryzbeck, 1988; Patton, Hibbert, Rosier, Carlin, Caust & Bowes, 1996; Patton, Carlin, Coffey, Wolfe, Hibbert & Bowes, 1998; Swendsen, Merikangas, Canino, Kessler, Rubio-Stipec & Angst, 1998). For sexual minorities, of same-sex and both-sex attracted people, a greater reliance tends to be placed on binge-drinking than in heterosexual people (Brewster & Tillman, 2011; Lindley, Walesmann & Carter, 2011; Midanik, Brabble & Trocki, 2007; Pega, Smith, Hamilton & Summerfield, 2012; Taliaferro, Lutz, Moore & Scipien, 2014). Self-medication with tobacco, drugs, and/or alcohol readily can become an 'addictive behaviour' with loss of control and unpleasant withdrawal effects when ceased. Capitalist culture
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enshrines a belief in individualism and personal control, and addictive behaviours are viewed as 'mental disorders'. Yet the most harmfully addictive substances are promoted through televisual and multi-media mass propaganda to consumers who repeatedly consume ever increasing amounts of sugary beverages in the form of cola and alcohol, fatty, salty and sugary foods, and possibly also tobacco, recreational drugs, and the pursuit of gaming and gambling (Marks, 1998). Governments and corporations, while doing everything possible to maximise taxation and profits, talk about 'responsible consumption', cleverly placing the onus of responsibility on the discontented and comfort-seeking consumer. Vandewalle, Moens and Braet (2014) explored the association between parental rejection and emotional eating in 110 obese young people aged 10 and 16 years attending a Belgian treatment centre for obesity. Participants completed questionnaires assessing maternal and paternal rejection, emotion regulation strategies and emotional eating. Vandewalle and colleagues found that the use of maladaptive emotion regulation strategies mediated the relation between maternal rejection and emotional eating. Paternal rejection itself was not found to be associated with emotion regulation or with emotional eating in the young people. These findings are in line with the CODT. Sutin, Ferrucci, Zonderman and Terracciano (2011) studied the association between personality and obesity across the adult life span. They investigated personality associations with adiposity and fluctuations in BMI in 1,988 participants over more than 50
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years. Sutin et al. modeled the BMI trajectory across adulthood and tested whether personality predicted its rate of change. Participants with higher scores on Neuroticism or Extraversion or lower scores on Conscientiousness had higher BMI, more body fat, and larger waist and hip circumferences. The strongest association was found for impulsivity. Participants who scored in the top 10% of impulsivity weighed, on average, 11 kg more than those in the bottom 10%. Longitudinally, high neuroticism and low conscientiousness, and difficulty with impulse control, were associated with weight fluctuations, measured as the variability in weight over time, in line with pathways 3 and 5 of the CODT. People with Type D personality experience increased negative emotions across time and situations and often choose not to share these emotions with others because they fear rejection or disapproval. Williams and Booth (2015) investigated the relationship between Type D and dietary intake in a crosssectional study with 187 healthy participants measuring Type D personality, dietary intake, and coping. Type D was associated with maladaptive coping and significantly less healthy food intake, including more consumption of fat and sugar, and significantly less consumption of F/Vs. This relationship was partially mediated by coping. The negative affect experienced by Type D personality is a risk factor for unhealthy eating, in line with pathway 3 of the CODT. Spoor et al. (2007) examined the association between negative affect, coping, and emotional eating in 125 eating-disordered women and 132 women from a Dutch community population. Both
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emotion-oriented coping and avoidance distraction were found to be related to emotional eating, while controlling for levels of negative affect. The authors concluded: â&#x20AC;&#x153;It is possible that emotional eaters may have fewer emotionregulation strategies that effectively downregulate negative emotions. They may then try to escape from these emotions by means of overeating as they believe or have learned that eating can possibly reduce aversive emotionsâ&#x20AC;? (Spoor et al., 2007, p. 373). This suggestion is in perfect alignment with pathway 3 in the CODT. Chao (2015) examined the relationships between chronic stress, food cravings, and BMI with a community-based sample of 619 adults. Chronic stress had a significant direct effect on food cravings, and food cravings had a significant direct effect on BMI. The total effect of chronic stress on BMI was significant. However food cravings partially mediated the relationship between chronic stress and BMI. Thus, chronic stress potentiates emotional eating and food cravings that, in turn, contribute to stress-related weight gain, as predicted by the CODT. We have already discussed in Chapter Two the variation in obesity prevalence across ethnic groups. In the US, non-Hispanic blacks have the greatest prevalence of obesity (35.7%), followed by Hispanics (28.7%) and non-Hispanic whites (23.7%), a pattern that is consistent across all census regions and greater among women than men (Pan et al., 2009). There are change in vulnerability throughout the life span. For example, Black US
65
women show heightened rates of obesity over the life course. For different social and cultural reasons, Black US menâ&#x20AC;&#x2122;s trajectories differ from those of Black womenâ&#x20AC;&#x2122;s. Early in life, Black men tend to lead active, athletic lives, but in middle age this strategy is reduced and they show increased rates of smoking, alcohol consumption, and illicit drug use. This process is not assumed to be inherently linked to racial group membership but can be attributed to the disproportionate distribution among Blacks of chronic, negative environmental, social, and psychological stressors, as well as the greater availability of environmental sources of unhealthy behaviors. It is hypothesized that Whites who lived under similar situations would almost certainly demonstrate similar processes and outcomes that are observed among the Black American population (Jackson et al., 2010). Summary: the CODT and implications for obesity prevention The evidence provides strong empirical support to the CODT especially from prospective studies. Pending systematic investigations to test the theory with prospective studies, there is strong empirical support for the theory that the human obesity epidemic involves a breakdown in psychological homeostasis. Approaches to treatment and prevention can be designed using CODT as shown in Figure 8. We return to the implications for prevention in Chapter Seven. Before doing so, we need to examine the neurobiological basis for the CODT and, in addition, its ability to explain the kindred phenomena of the addictions.
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Four: Neurobiology
Homeostasis is omnipresent in nature and all living things. It occurs within individual organisms, in social milieu, and in the economic and political environment. At the physiological, psychological and social levels, smooth functioning of healthy organisms relies upon the successful operation of homeostasis. Wherever there is homeostasis, however, there is the potential for dyshomeostasis. When homeostasis is disrupted, the well-being of an individual, family or population is placed in jeopardy.
We
have argued in the preceding Chapters that the principle of dyshomeostasis provides a scientific explanation of obesity (Marks, 2015a). The key scientific dilemma is to understand how obesity can happen in the first place, and on the global scale that exists at the present time. There is a theoretical vacuum about the causes of obesity that defies logic and imagination. A phenomenon that is so pervasive cannot lie beyond explanation in science. The first place to look for an explanation of obesity dyshomeostasis is in neurobiology. In the obese person, something has gone wrong within the psychoneuroendocrinal system. Clearly, the mechanisms responsible for feeding control have been disrupted.
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But what is the nature of the disruption? And why does it happen in one individual rather than another? The explanation, I suggest, is a relatively simple but neglected one: obesity is a form of dyshomeostasis. What Is Dyshomeostasis? According to the CODT, obesity occurs as a consequence of a disruption to the homeostatic mechanisms that regulate the control of eating. When addressing the spectrum of clinical conditions that are the concern of medical and clinical science, the idea of homeostasis imbalance is an ancient one. Since Hippocratus and Galen, the history of clinical medicine has continued to be associated with the principal of dyshomeostasis. What is surprising is that dyshomeostasis has not previously been cited as a cause of obesity. In this chapter, the neurobiological basis for the CODT will be elaborated. Interesting parallels will become apparent between eating and other forms of consumption that rely on similar neurobiological mechanisms: the addictions to nicotine, alcohol, illicit and prescribed drugs and also behavioural addictions. The following sections discuss biological mechanisms that relate to the psychological and social issues included in the “Circle of Discontent”. In so doing, the opportunity to lend “a truly integrative biopsychosocial lens” is embraced, as suggested by Rosenbaum and White (2016). In a socio-cultural environment that promotes widespread body dissatisfaction, angst and depression, feedback loops are producing excessive consumption of unhealthy processed foods
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that, over a protracted period, causes obesity in large numbers of vulnerable people. Multiple clinical studies in different areas of medicine demonstrate the primary role of homeostasis in healthy functioning and also the consequences of dyshomeostasis. Homeostasis can be overloaded or over-ridden with too strong a flow of inputs or outputs that disrupt its normal functioning: â&#x20AC;&#x153;The homeostatic behaviour of inflow controllers breaks down when there are large uncontrolled inflows, whereas outflow controllers lose their homeostatic behaviour in the presence of large uncontrolled outflowsâ&#x20AC;? (Drengstig et al., 2012). Homeostasis can be disrupted anywhere and perturbations will inevitably occur in normal functioning (Richards, 1960). Competition for control can also be lost to another powerful system that offers hedonic pleasure in lieu of the moderating influence of containment and restraint. The internal struggle between these two systems is only partially a conscious one. It is noticed in the eternal conflict between having another helping and thinking about one's waistline. Many examples of dyshomeostasis exist in clinical medicine. Hans Selye reported that a persistent environmental stressor (e.g., temperature extremes), together with an associated homeostatic hormonal response, leads to tissue injury that he termed a 'disease of adaptation' (Selye, 1946). Intestinal homeostasis breaks down in inflammatory bowel disease (Maloy and Powrie, 2011) and in the microbial ecology of dental plaque causing dental disease (Marsh, 1994). This form of dyshomeostasis can result from local infection and inflammation and give rise to complications
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that affect the neuroendocrinal system (Maynard et al., 2012). An altered balance between the two major enteric bacterial phyla, the Bacteroidetes and the Firmicutes, has been associated with clinical conditions. Within the microbiota of the gut, obesity has been associated with a decreased presence of bacteroidetes and an increased presence of actinobacteria (Turnbaugh & Gordon, 2009; Ley, 2010). Kamalov, Bhattacharya and Weber (2010) proposed a dyshomeostasis theory of congestive heart failure. Craddock et al. (2012) suggested a zinc dyshomeostasis hypothesis of Alzheimer's Disease. Gut-Brain Relationships Homeostatic regulation within the neuroendocrinal system has been associated with feeding control. Cortical areas conveying sensory and behavioral influences on feeding provide inputs to the Nucleus Accumbens (NAc) and the Lateral Hypothalamic Area (LHA) is the site of homeostatic and circadian influences (Saper et al., 2002). Hormones such as leptin circulate in proportion to body fat mass, pass the blood-brain barrier, and act on the neurocircuits that govern food intake (Morton et al., 2004). Through direct and indirect actions, it is hypothesized that leptin diminishes the perception of food reward while enhancing the response to satiety signals generated during food consumption to inhibit feeding and lead to meal termination. Another important hormone is ghrelin, the only known mammalian peptide hormone able to increase food intake. Ghrelin (GH) also responds to emotional arousal and stress (Labarthe,
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Fiquet, Hassouna, Zizzari et al., 2015; MĂźller et al., 2015). In chronic stress, increased GH secretion induces emotional eating by acting on the hedonic/reward system. As GH has anxiolytic action in response to stress, emotional eating is an adaptative response that helps to control excessive anxiety and to ameliorate depression (LaBarthe et al., 2015). In obesity, studies have shown a reduced ability to mobilize GH in response to stress or central GH resistance at the level of the hedonic/reward system that may explain the inability to cope with anxiety and increased susceptibility to depression (Figure 9). Reciprocally, studies have shown that people with depression have increased susceptibility to obesity and eating disorders (Marks, 2015a).
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Recent findings suggest that the satiety response in obese children and adults may be weakened. The physiological response to meal intake of gut-derived appetite and satiety hormone signals differs between obese and healthy-weight children. A systematic review and meta-analysis of studies investigating the acute postprandial response of gastrointestinal appetite hormones, GH and PYY, to meal intake in obese children was undertaken by Nguo, Walker, Bonham and Huggins (2015). Obese compared with healthy-weight children had attenuated responses in both GH and PYY at 60â&#x20AC;&#x2030; min (N=5 studies; n=128-9 participants) and 120 min postprandial (N=4 studies; n=100 participants). These findings suggest that obese children experience abnormally low satiety to meal intake that could lead to eating extra portions or snacking between meals, two characteristics of PLWO. In addition to leptin and GH, other lipid messengers that modulate feeding by sending messages from the gut to the brain have been identified. For example, oleoylethanolamine has been associated with control of the reward value of food in the brain (Lo Verme et al., 2005; Tellez et al., 2013). Mice fed a high-fat diet had abnormally low levels of oleoylethanolamine in their intestines and did not release as much dopamine compared to mice on lowfat diets. Thus, alterations in gastrointestinal physiology induced by excess dietary fat may be one factor responsible for excessive eating in the obese (Tellez et al., 2013). The CODT holds that obesity is a created by the imposition of hedonic comfort eating and drinking to ameliorate negative affect. The Circle of Discontent is paralleled by the model of the
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hedonic/reward response to GH suggested by Alexandra LaBarthe et al. (2014) (Figure 9).
In Figure 9, “Chronic stress” and
“Anxiety/Depression” are merged into the single construct, “Negative affect”. Similarly, in the context of obesity, “Hedonic reward/response” and “Emotional eating” are also operationally a single process. With these amendments, it can be seen that the simple diamond structure of the Circle of Discontent emerges from the LaBarthe model (Figure 10) providing the CODT with a framework inside neurochemistry.
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Obesity Dyshomeostasis in Neurobiology Traditionally, the control of feeding has been associated with the hypothalamus (Kelley, Baldo, Pratt & Will, 2005). Circulating factors in the blood modulate the activity of energy-sensing neurons in the arcuate nucleus, that modulate food-directed behaviours. This process is achieved by activation of outputs from lateral hypothalamic regions to thalamo-cortical systems, central autonomic effectors and motor pattern generators. There is a convergence of inputs from amygdala, prefrontal cortex, and the nucleus accumbens shell that allow direct modulation of feeding behaviours using cognitive and affective signalling. These avenues of influence provide the entry point for the Circle of Discontent. When the environmental conditions: (A) are obesogenic, due to the ready availability of highly palatable high-energy foods; (B) stressful, due to the presence of stigma, depression and anxiety; and (C) engender body dissatisfaction, due to the omnipresent socio-cultural thin-ideal, we have the 'Perfect Storm' for obesity formation. According to CODT, the cognitive and affective processes of the Circle of Discontent over-ride feedinghomeostasis leading to a break down. The amygdala, prefrontal cortex and nucleus accumbens participate in the regulation of both affect and feeding. The amygdala consists of a group of nuclei involved in emotional learning and expression, a key element of the neural basis of emotion. Damage to the amygdala may lead to an increased threshold for emotional perception and expression, impairments in emotional learning, deficits in the perception of facially expressed
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emotion, and impaired memory for emotional events (Cardinal, Parkinson, Hall and Everitt, 2002). Among younger adults, it has been found that the ability to wilfully regulate negative affect, enabling effective responses to stressful experiences, engages regions both of the prefrontal cortex (PFC) and the amygdala. Urry et al. (2006)
tested whether the PFC and amygdala responses
during emotion regulation predict the diurnal pattern of salivary cortisol secretion. Urry et al. also tested whether PFC and amygdala regions are involved in emotion regulation in older (62-64-year-old) individuals. They measured brain activity using functional magnetic resonance imaging as participants regulated by intentionally increasing or decreasing their affective responses or attended to negative picture stimuli. Urry et al. also collected saliva samples for one week at home for cortisol assay. Increasing negative affect resulted in ventral lateral, dorsolateral, and dorsomedial regions of PFC and amygdala activation. The predicted link between brain function in the PFC and amygdala occurred while reducing negative affect in the laboratory and diurnal regulation of endocrine activity in the home environment (Urry et al., 2006). The authors concluded that functional coupling between the PFC and the amygdala enables effective regulation of negative emotion and the activity of PFCâ&#x20AC;&#x201C;amygdala circuitry during regulation of negative affect predicts longer-term regulation of endocrine activity that may be important for health and well-being. These connections between the PFC and the amygdala play a key role in the CODT. In the CODT, negative affect causes increased comfort feeding.
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This causal relationship is made possible by the fact that the hypothalamo-pituitary-adrenal (HPA) axis regulates both feeding and affect and, thus, each process influences the other in eliciting increased consumption (Maniam and Morris, 2012). It has been established that negative affect induces increased comfort food intake and body weight gain in humans (Dallman et al. 2003). In rats chronic stress produces decreases in corticotropin-releasing factor (CRF) mRNA in the hypothalamus. Depressed people who overeat have decreased cerebrospinal CRF, catecholamine concentrations, and hypothalamo–pituitary–adrenal activity. It has been proposed that people eat comfort food in an attempt to reduce the activity of the chronic stress-response network with its attendant anxiety (Dallman et al., 2003; Dallman et al., 2004). Research from Dallman et al. (2003, 2004) indicates that consumption of foods high in fats and carbohydrates reduces anxiety via feedback to the HPA axis. In chronic stress, negative feedback loops through which cortisol regulates release of CRF break down as glucocorticoid receptors are down-regulated and the release of CRF continues. Release of CRF associates with feelings of anxiety as CRF mRNA expression in the amygdala is increased. Thus, consuming comfort foods facilitates the “shutdown” of the stress response by regulating the release of CRF. Abdominal fat deposits from comfort foods signal increased metabolic energy stores that, in turn, enables decreases in the expression of CRF mRNA in the hypothalamus via the inhibition of catecholamine production in the nucleus of the tractus solitarius. Thus, eating comfort food reduces anxiety by inhibiting the release
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of CRF. Obesity is associated with neuroendocrine disturbances, in which the HPA axis plays a central role. The HPA axis is stimulated by negative affect that is associated with discrete, periodical elevations of cortisol (Bjรถrntorp and Rosmond, 2000). Prolonged HPA axis stimulation is followed by a continuous degradation of the mechanisms controlling eating and affect. The net effects of neuroendocrine-endocrine pertubations in the HPA axis is insulin resistance and accumulation of body fat. These are effects of cortisol combined with diminished secretion of growth and sex hormone secretions. The outcome is hypothalamic arousal and the Metabolic Syndrome. The feedback regulation of the HPA axis has a key position in this chain of events with control being mediated by glucocorticoid receptors (Bjรถrntorp and Rosmond, 2000). The role of the HPA axis and cortisol in emotional eating is a strong one and patients with abdominal obesity have elevated cortisol levels.
Epel, Lapidus, McEwen and Brownell (2001)
hypothesized that high cortisol reactivity to stress would lead to eating after stress, given the associations between cortisol with both psychological stress and hunger mechanisms. Fifty-nine healthy pre-menopausal women received both a stress session and a control session on different days. High cortisol reactors were found to consume more calories on the stress day compared to low reactors, but similar amounts on the control day. High reactors ate significantly more sweet food across days and increases in negative mood following the stressors was also significantly
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related to greater food consumption. Similar findings were recently reported by Hewagalamulage et al. (2016) who also observed a strong association between HPA axis activation and energy homeostasis. Like people, sheep that are high cortisol responders were found to have a greater tendency to obesity than low cortisol responders. These results suggest that the cortisol response to stress influences subsequent eating behaviour. A further relevant finding is that the impact of negative affect, whether in the form of anxiety, depression or stress, is modulated by the PFC. The PFC appraises, evaluates, interprets and monitors the meaning and relevance of information from multiple sources and points of view, including one's perception of the appearance of the body reflected in a mirror.
A person's body
dissatisfaction is at once a cognitive and affective product based on cognitive appraisal and autochthonous perception of the body's attributes and one's feelings about these. The PFC generates body dissatisfaction and, in response, the HPA axis produces glucocorticoids that regulate consumption. In addition to the mediation of stress responses by the HPA axis, recent studies have observed that there is an alternative system for stress mediation in circulating GH acting upon the amygdala (Meyer et al., 2013). In regard to the two systems of feeding control, both of which use GH signalling, we can agree with MĂźnzberg et al. (2016) who point out that: â&#x20AC;&#x153;The traditional dichotomy between homeostatic and nonhomeostatic/hedonic systems responsible for the control of appetite and regulation of body weight, although heuristically
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still useful, no longer adequately describes the extensive anatomical and functional interactions between the two systems. In addition, much of the output of this larger interactive system is bypassing awareness.â&#x20AC;? Because the two systems can override one another, the Circle of Discontent gains traction as an explanation of obesity.
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A provisional description of the neurobiological substrate of the Circle of Discontent is summarised in Figure 11. The model shows feedback loops between the pre-frontal cortex, the amygdala, the HPA axis and visceral adiposity as mediators of body dissatisfaction, negative affect, eating behaviour, and obesity respectively. The evidence from neurobiology suggests that the homeostasis of eating can be overridden by the hedonic reward system acting to relieve stress through the excessive consumption of palatable foods. Furthermore, eating is controlled by a complex neural network including the mesocorticolimbic pathway, which consists of the ventral tegmental area, nucleus accumbens, amygdala, hippocampus and prefrontal cortex. These regions are the neural substrates of mood, pleasure, desire, experience of self, body satisfaction and self recognition, and significantly influence eating patterns. The hedonic system overrides and disrupts homeostatic control when there are chronic levels of negative affect and easy accessibility to palatable energy-dense foods. In PLWO, eating to excess is produced by a Circle of Discontent, a difficult-to-control self-medication of hedonic reward to assuage stress, anxiety and depression. Entering and Exiting the Circle of Discontent A key question concerns entry and exit to the Circle of Discontent (DiClemente and Delahanty, 2016). Who enters the Circle for the first time, who stays and who leaves, and is it a revolving door? In a person's lifetime, when is entry most likely to happen? Once inside, what are the prospects of making an exit?
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Important work on behaviour change has been carried out by Carlo DiClemente and his group (DiClemente, 2003; DiClemente, Delahanty and Havas, 2015). If the theory is to have true explanatory value, the issue of change needs to be addressed by the dyshomeostasis theory. As stated by DiClemente and Delahanty (2016): â&#x20AC;&#x153;The challenge is to understand how early problems in attachment may influence some to overeating or anorexia, others to sociopathy and drug abuse, others to depression or anxiety, and still others to being successful professionals. It depends on how the experiences, environment, knowledge, and opportunities filter the early experiences and influence movement forward in the process of change for these different outcomes.â&#x20AC;? Obesity Dyshomeostasis Theory describes two main systems, the Circle of Discontent (COD) and the Motivation and Energy Mobilization (MEM) system (Figure 6). In the Circle of Discontent, the levels of body dissatisfaction, negative affect and high-energy consumption run out of control. As we have seen, a key connection in the Circle is between chronic stress and comfort eating (Dallman et al., 2003). In the MEM system, lowered motivation causes changes in restraint, dietary intake and activity, which cause reductions to subjective well-being, mobility, and positive affect. The whole complex establishes unhealthy eating habits, low activity levels, negative affect, overweight and obesity. It is commonly assumed that the primary cause of obesity is 'lifestyle', the learning of unhealthy habits and behaviours; at worst,
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PLWO are seen as greedy and lazy. These stereotypes are wrong and fly in the face of all of the evidence from scientific research. In fact there are many drivers over a person's lifetime that can push and pull him or her towards entry to the Circle. The majority of significant influences occur in the first few years of life, well before the person becomes an adult and can develop a so-called 'lifestyle'. To clarify this point, we can consider the analogy of a lottery in which people are allocated tickets at different critical stages. Imagine that tickets are issued at different critical points in the life cycle starting from the moment of conception. The tickets carry percentage points that are weighted according to the importance of each life transition as a potential obesity determinant. At any time, a person's BMI is linearly related to the total number of 'obesity points' they have been allotted. A schematic plan of obesity determinants is shown in Table 2.
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The single largest determinant is heredity (50 percentage points) over which the individual has absolutely no control. In this case the lottery analogy is completely accurate. Genetic predisposition, prenatal maternal stress, including problems with the partner and epigenetic factors all have an influence (Sominsky and Spencer, 2014; Talge, Neal and Glover, 2007). Socioeconomic disadvantage in the form of poverty causes chronic life stress at all stages from infancy and adolescence through to adulthood. People living with low levels of income suffer social oppression, chronic stress and multiple episodes of negative affect, restraint and hedonic reward eating of fatty and sugary foods leading to obesity (Drewnowski and Specter, 2004; McLaren, 2007; Monteiro et al., 2004). Early life stress including general parenting, parent childhood abuse and attachment style influence appetite, feeding behaviour and metabolism throughout life (Felliti, 1993; Felliti et al., 1998; Puig et al., 2013; Sleddens et al., 2011; Sominsky and Spencer, 2014). The prenatal period and adolescence are thought to be critical periods for the development of obesity that persists into adulthood (Dietz, 1997). The field of epigenetics and obesity is relatively new but early steps are being made to identify biomarkers for obesity. Findings suggest that several epigenetic marks are modifiable, not only by changing the exposure in utero, but also by lifestyle changes in adult life, so there is some potential for interventions to reform unfavourable epigenomic profiles (Van Dijk et al., 2015). However, the degree to which epigenetic influences are open to reversal currently remains uncertain. Probably they can be reversed to some degree.
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Genetic and neurobiological factors help to explain why many people develop obesity while others head towards other consumption-related conditions such as alcoholism, nicotine or drug addiction. Once again, GH helps to tell the story.
Ghrelin
levels in children with Prader Willi Syndrome are 3- to 4-times higher compared with BMI-matched obese controls (Haqq et al., 2003). Ghrelin shows wide differences between obese and normal weight adults (Tschop, Weyer, Tataranni, Devanarayan et al., 2001) and among adolescents with different kinds of disorders such as anorexia nervosa and obesity. Baseline GH concentrations increased and decreased, respectively, to a mixed meal in anorexic and obese female adolescents (Stock et al., 2005). Low plasma GH has been independently associated with type 2 diabetes, insulin concentration, insulin resistance, and elevated BP (Pรถykkรถ, Kellokoski, Hรถrkkรถ, Kauma et al., 2003). Ghrelin levels were also found to be significantly higher in female alcohol-dependent patients compared to controls, but not in male alcoholics (Wurst, Graf, Ehrenthal, Klein et al., 2007). For many people, entry into the COD is impossible to avoid. Modern living conditions are guaranteed to deliver high proportions of the population with overweight and obesity. It has very little to do with conscious choice.
For a significant segment of the
population, overweight and obesity are a statistical inevitability. Once inside the Circle, is there any escape? As shown in Table 2, the majority of available 'tickets' for the obesity 'lottery' are allocated by the the time a person reaches adulthood. obesity is 90% determined before early adulthood with only limited scope for
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change.
The obesity die has been cast. If we allow for the
possibility that around half of epigenetic influences on obesity might be reversible, and a further 10% for potentially reversible lifestyle determinants,
it must be concluded that 80-90% of
obesity determinants are irreversible by non-surgical treatment. The Circle of Discontent is vicious and self-sustaining. Exit options are few. Breaking out of the vicious circle requires momentously strong motivation and a transformational change in eating habits, lifestyle and philosophy of living. For the majority of sufferers, is a persistent and intractable condition. A small average weight loss of 2-4 kilograms may be achievable by committed adherence to a structured diet regime (Dansinger et al., 2005) but diet systems generally do not provide the keys to a cure (Foster et al., 2003; Katz, 2002). Psychological therapies lead to disappointing outcomes, typically producing a weight loss of a few kilograms
(Shaw et al., 2005). Drug treatments involve safety
issues and also yield relatively low levels of weight loss. Weight loss relative to placebo ranges from 3% for orlistat and lorcaserin to 9% for phentermine plus topiramate-ER at one year (Yanovski & Yanovski, 2014). The only effective treatment for long term weight loss in patients with clinical obesity is surgery, which is costly, imperfect and inaccessible for the majority of patients (Buchwald et al., 2004). Within current knowledge, the determinants of obesity are practically irreversible; the illness is persistent and almost untreatable. To give any other impression to patients is unethical and misleading. A person inside the Circle of Discontent is likely
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to remain inside. Their only exit point most likely will be an early death. To offer treatments that are minimally effective placebos is unethical. Yet the weight loss industry is relentless and profits from the false hopes of millions. Many charlatans sell snake oil placebos to exploit PLWO who are clutching at straws of hope. There is no other area of medicine where the hippocratic oath and the trust of patients is so flagrantly and repeatedly smashed to smithereens. Exploiters of victims of obesity should hang their heads in shame. Until new, properly vetted and approved endocrinological treatments become available, all necessary resources should be directed towards prevention.
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Five: Addictions Manifestations of dyshomeostasis can be observed in multiple fields of psychology and medicine. In the case of obesity, it has been shown that hedonic reward has a disruptive effect of weight homeostasis. It is interesting to examine kindred phenomena in the field of addictions. As many investigators have noted, it is apparent that food and drug consumption share some common features and neural substrates, with opioid receptors playing a mediational role in both feeding and reward (Kelley et al., 2005). For example, Saper et al. (2002) stated: â&#x20AC;&#x153;endogenous opioid systems regulate the hedonic value of food intake independently from the ongoing metabolic needs of the individual. Furthermore, food deprivation, which enhances the hedonic response to food, also increases the motivational value of non-food rewards, such as psychostimulants ...intracranial self-stimulation â&#x20AC;Ś and heroin intakeâ&#x20AC;?. This perspective places food and addictive drugs into a similar category. However, while similarities certainly do exist, there are also differences between the two types of consumption (DiLeone, Taylor and Picciotto, 2012). While eating is necessary for survival, and susceptible to selection pressures during evolution, drug
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addiction begins as a voluntary choice, and then appropriates a subset of reward pathways that evolved for feeding (Figure 12).
The CODT has particular relevance to the addictions to tobacco, alcohol, illicit drugs, and behaviours such as gambling and gaming.
These addictions involve compulsion and loss of
control that can be costly to individuals and families in both health and monetary terms; all have been associated with chronic stress
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and negative affect in the form of anger, anxiety or depression (Breslau et al., 1993; Helzer, and Pryzbeck, 1988; Patton et al., 1996, 1998; Swendsen et al., 1998). Diverse consumption patterns across different population groups prove that â&#x20AC;&#x153;no size that fits allâ&#x20AC;? but the causal mechanisms of compulsive consumption remain essentially the same. Excessive consumption is a hedonic strategy to increase reward. It reinforces the operant behaviour by reducing negative affect and dissatisfaction. Alcohol use, tobacco smoking, recreational drugs, gambling, gaming, shopping, internet use, TV viewing, sports, fitness training, running, swimming, tanning, and sex are all activities that can be addictive. It suffices here to consider tobacco addiction. Smoking a cigarette is a homeostatic behaviour that corrects the imbalance of the dopaminergic reward system and reduces dissatisfaction and negative affect. The different kinds of homeostasis complement each other to stabilize physiological and psychological well-being. Tobacco smoking is one of many examples of unhealthy habits that are strengthened by hedonic reward and the palliation of negative affect in a Circle of Discontent. Nicotine addiction is the result of neurochemical changes to the brain. Long-term tobacco use results in physical dependence and a compulsion to use tobacco. The cigarette is the most efficient and rapid method for delivering nicotine to the brain. Nicotine from cigarette smoke is quickly absorbed in the lungs and rapidly passes into the brain where it binds to specialized nicotinic acetylcholine receptors (nAChRs). Stimulation of nAChRs by nicotine results in the release of a variety of neurotransmitters in
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the brain of which dopamine is the most important because it produces pleasure. In an addicted smoker, nicotine therefore produces pleasure, arousal, and mood modulation. However, the effects of a single cigarette are short-lived and the smoker requires frequent top-ups of nicotine to maintain a state of cognitive and affective stability. For the addicted smoker, smoking is a homeostatic process that maintains the required level of nicotine in the brain (Prochaska and Benowitz, 2016). In chronic nicotine addiction, tolerance develops so that more nicotine is needed to maintain normal brain functioning and nicotine is required to deliver the same neurochemical effect.stopping smoking, or waiting for a longer interval between smokes, is associated with withdrawal symptoms of irritability, anxiety, poor concentration, hunger, weight gain and problems getting along with others. Nicotine addiction is therefore a 'twoedged sword' that is sustained both by positive effects of pleasure and arousal and by the avoidance of the unpleasant effects of nicotine withdrawal. Conditioning sustains tobacco use through the reinforced association between smoking and 'triggers' in the form of specific behaviours such as drinking coffee or alcohol, talking on the phone, driving a car, and/or completing a meal. Sensorimotor drug-associated cues or 'triggers' become associated with the act of smoking and become cues for smoking and maintain tobacco use (Sulzberger and Marks, 1977; Marks, 2005). Research with cocaine and other drugs suggests that dopamine release occurs in the presence of the triggers alone (Ito, Dalley, Robbins and Everitt, 2002).
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In the formation of tobacco addiction, the novice inhales tobacco smoke that, in the early stages, produces toxic and unpleasant sensations in the mouth and throat. However, with each inhalation, these unpleasant sensations are replaced by feelings of satisfaction as the addiction becomes strengthened. The feelings of satisfaction grow stronger as the habit is reinforced by the dopamine release and the accompanying reduction of negative affect. As the habit strength increases, the smoker feels withdrawal symptoms that increase in intensity the longer he/she waits before lighting the next cigarette. Symptoms of addiction appear within days or weeks after occasional smoking first begins (Russell, 1990). The addicted smoker uses cigarettes to regulate mood control in a type of self-medication, titrating the dose to match momentary fluctuations in his or her mood. Smokers quickly learn to regulate their nicotine intake on a puff-by-puff basis, a strategy that is acquired early in the tobacco-dependence process (Collins et al., 2010). For this reason, smokers report that cigarettes help to relieve their feelings of stress (Figure 13). Nicotine addiction exacerbates stress yet yields the delusory impression to smokers that it is stress-reducing. Contrary to the subjective experience of smokers that leads them to report that smoking reduces stress, smokers' stress levels actually are higher than those of nonsmokers, and adolescent smokers report increasing levels of stress as they develop regular smoking patterns (Parrott, 1999). Nicotine consumption rapidly increases heart rate, and blood
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pressure (Rose, 2001). Thus, the alleged â&#x20AC;&#x153;relaxation effectâ&#x20AC;? of smoking is a consequence of reversing the tension and irritability that develop during nicotine depletion between cigarettes. Addicted smokers need nicotine to feel 'normal' (Parrott, 1999). This situation is exactly paralleled by other drug use. Unpleasant withdrawal symptoms are associated with increases in urges and intentions to take any drug to which a person is addicted. In addition, addicted individuals rate coping with negative affect as the prepotent motive for drug use (Baker et al., 2004). Smoking
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cessation leads to reduced stress. How addicts react to drug-associated cues provides one measure of their drug dependency on the drug. The cue-reactivity procedure exposes addicts to a variety of drug-related stimuli while self-report of craving and physiological responses are monitored. Meta-analytical techniques have been used to select and evaluate results from 41 cue-reactivity studies that compared responses of alcoholics, cigarette smokers, cocaine addicts or heroin addicts to drug-related versus neutral stimuli (Carter & Tiffany, 1999).
The
general profile of effect sizes across addict groups for drug-related stimuli was increased heart rate (+0.26) and sweat gland activity (+0.40) and decreased skin temperature (-0.24). One mechanism common to all types of addiction is the increased dopamine transmission that gives an immediate feeling of pleasure and satisfaction. The increase in dopamine activity from nicotine results in pleasant feelings of satisfaction for the smoker, but the subsequent decrease in dopamine leaves the smoker craving for more cigarettes (Gamberino & Gold, 1999; Arias-CarriĂłn et al., 2010). The level of negative affect influences how much an individual tends to consume, whether it is food, smoking, alcohol, other drugs, or behaviours and how intensely one craves and, ultimately, whether an abstinent individual will return to harmful consumption (Holgate and Bartlett, 2015). Drug addiction has been defined by Koob (2015) as a threestage cycle â&#x20AC;&#x201C; binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation â&#x20AC;&#x201C; that involves homeostatic changes in the brain reward and stress systems. Two primary sources of
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reinforcement, positive and negative reinforcement, are hypothesized to play a role in this process.
The negative
emotional state that drives negative reinforcement is hypothesized to derive from dysregulation of key neurochemical elements involved in the brain reward and stress systems. Specific neurochemical elements in these structures include not only decreases in reward system function (within-system opponent processes) but also recruitment of the brain stress systems mediated by corticotropin-releasing factor (CRF) and dynorphin- Îş opioid systems in the ventral striatum, extended amygdala, and frontal cortex (both between-system opponent processes). CRF antagonists block anxiety-like responses associated with withdrawal, block increases in reward thresholds produced by withdrawal from drugs of abuse, and block compulsive-like drug taking during extended access. Excessive drug taking also engages the activation of CRF in the medial prefrontal cortex, paralleled by deficits in executive function that may facilitate the transition to compulsive-like responding. Neuropeptide Y, a powerful anti-stress neurotransmitter, has a profile of action on compulsive-like responding for ethanol similar to a CRF1 antagonist. Blockade of the Îş opioid system can also block dysphoric-like effects associated with withdrawal from drugs of abuse and block the development of compulsive-like responding during extended access to drugs of abuse, suggesting another powerful brain stress system that contributes to compulsive drug seeking. The loss of reward function and recruitment of brain systems provide a powerful neurochemical basis that drives the
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compulsivity of addiction (Koob, 2015, p.7). In the case of alcohol use, which is often associated with tobacco smoking, chronic consumption of alcohol alters the normal function of the affect system causing an increased susceptibility to stress (Adinoff et al., 1998). This increases the likelihood of progression as it produces a cycle of degeneration where exposure to stress leads to escalations in consumption, further reducing the ability to cope with stress and shortening the length of intervals between periods of abstinence. The combined use of several substances leads to many individuals in the population having multiple addictions (Anthony, Warner and Kessler, 1994; Lorains, Cowlishaw and Thomas, 2011). In such individuals there are multiple Circles of Discontent operate in complementary fashion. Figure 14 illustrates a model of a person addicted to nicotine, ethanol, cocaine, and gambling. The four concurrent addictions each has its own homeostatic system. The same person could quite possibly have other addictions as well (e.g. to caffeine, other drugs, the Internet) and the already complex diagram would need to be extended to include these. The different addictions have associative connections and any one of the behaviours may act as a trigger for one or more of the others. The brain areas mediating appetitive drug seeking and addictive behaviours may differ between addictions, but include at least some of the areas shown in Figure 12.
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The four addictions reinforce one other and, after prolonged exposure, the addictions become closed off from external influence and obsessive-compulsive in nature (Vanderschuren and Everitt, 2004; Volkow and Fowler, 2000). The total system illustrated in Figure 14 becomes self-sustaining with all of the addictions under the control of a single hedonic reward system designed to palliate negative affect by repeated appetitive behaviours. As previously mentioned, the peptide GH activates reward systems, and its receptor (GHS-R1A) appears to be required for alcohol, cocaine, amphetamine and nicotine induced reward (Jerlhag and Engel, 2010). The hedonic reward system, under the influence of GH, overrides the normal functioning of homeostasis, maintaining the Circle of Discontent and placing the individual at significant longterm risk. As noted, smokers report that smoking relaxes them but physiologically they actually register higher levels of stress. Ng et al. (2003) studied associations between perceived stress and fat intake, exercise, alcohol consumption, and smoking behaviours. Data were from surveys of 12,110 individuals in 26 worksites and linear regression analyses examined cross-sectional associations between stress level and health behaviours. Analyses were stratified by gender and controlled for demographics. High stress levels were associated with a higher fat
diet,
less
frequent
exercise, cigarette smoking, recent increases in smoking, less self-efficacy to quit smoking, and less self-efficacy to not smoke when stressed. These findings are consistent with the CODT by revealing a causal relationship between chronic stress and
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increased consumption. The CODT offers a coherent, parsimonious explanation of obesity and the addictions and indicates the significant causal role of chronic stress.
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Six: Motivation In this brief chapter, I clarify the motivational aspects of the CODT. Motivation is a key driver of behaviour and an essential element in any theory of behaviour change. In a person living with overweight and obesity, motivation, or its lack, is often stated to be one of the key issues. Motivation has been highlighted in a recent critical commentary on the CODT by Pelletier, Guertin, Pope and Rocchi (2016). They focus their remarks by reference to the motivation perspective of Self-Determination Theory (SDT; Deci and Ryan, 1985). They suggest that the CODT “does not explain why some people exposed to the same conditions (e.g., abundance of unhealthy foods, negative life events) do not gain weight and become obese” and that it emphasizes strategies that do not consider individuals as active agents of their own behaviours. There can be no question that motivation plays a pivotal role in human behaviour change and in the aetiology of obesity. As previously stated: “It remains necessary to explain how or why overweight or obesity can develop in a susceptible individual, and why some individuals develop it and not others” (Marks, 2015a). The dyshomeostasis theory of health holds that human health is regulated at all times by multiple systems of homeostasis that are
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operating in parallel and in cascades all directed towards stability of function. All of the many thousands of homeostatic systems are interconnected and complementary in maintaining the stability and equilibrium of the human organism (Figure 9).
The Circle of
Discontent is only one of the systems relevant to obesity and the addictions. Of equal importance to the COD is the Motivation and Energy Mobilization (MEM) system. The MEM system incorporates Motivation, Restraint, Diet, Physical Health, Activity, Subjective Well-Being, Mobility and Affect. As shown in Figure 5, the MEM and COD systems are equally involved in regulating Physical Health and Affect, but only the MEM system includes individual motivation. Without any doubt, the MEM system is significant in the maintenance of healthy habits and behaviours and, when things go wrong, in the generation of obesity and addictive behaviours. Self-Determination Theory It is helpful to consider the regulatory styles within SDT that are differentiated along an alleged continuum that ranges from nonself-determined styles
(i.e. amotivation, external regulation, and
introjection) to self-determined ones (i.e. identification, integration, and intrinsic motivation). As suggested by Pelletier et al. (2016) there are parallels between SDT concepts concerning motivational style and the CODT. The Circle of Discontent is a perfect fit to the profile of 'Controlled Motivation' within SDT. Studies by Pelletier and colleagues have provided interesting evidence concerning the motivation style that is most likely to be
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associated with unhealthy eating, depressive symptoms and increased BMI, namely 'Controlled Motivation' (Pelletier, Dion, Slovenic-D'Angelo & Reid, 2004). The findings from Pelletier et al. (2004) revealed a response pattern that is consistent with the CODT, namely unsuccessful regulation of eating, a concern with quantity but not quality of food eaten, bulimic and depressive symptomatology, low self-esteem, low life satisfaction, and increased BMI, all significantly associated with controlled regulation (Table IV, Pelletier et al., 2004). On the other hand, autonomous regulation was found to be significantly correlated with a concern for quality rather than quantity of food eaten, with successful regulation of eating, healthy eating behaviors, high selfesteem and high life satisfaction. One could not wish for a more positive confirmation of the CODT. It would appear to be the case that the two profiles of Controlled Motivation and Autonomous Motivation represent the opposite ends of the homeostasis continuum. Autonomous Motivation brings satisfactory internalized control of eating behaviours, relatively high life satisfaction and positive affect, a state of positive homeostasis.
Controlled Motivation, on the other hand, is a
component of homeostatic imbalance in which the individual fails to enjoy, or internalize, the desired goals of eating behaviour (Ryan & Deci, 2006). The person whose motivational system is ruled by the Circle of Discontent is perfectly represented by the 'Controlled Regulator', a person whose eating habits are running out of control and whose life satisfaction, and affect levels have deteriorated. According to SDT, Controlled Regulation occurs in
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three forms:
1) The 'Introjected Regulator', not wanting to be ashamed of how they look and eat, feeling that they must absolutely be thin, feeling they would be humiliated if they were not in control of their eating behaviors.
2) The 'External Regulator', other people close to them insist that they do things a certain way, other people close to them will be upset if they donâ&#x20AC;&#x2122;t eat well, people around them will nag them to do it, or it is expected of them.
3) The 'Amotivated Regulator', the worst case scenario, feeling helpless and hopeless, not really knowing what to do, having the impression that they are wasting their time trying to regulate their eating behaviors, not seeing how their efforts can ever lead to eating healthily or helping to improve their health. In SDT, motivation is King, with a commanding role in need satisfaction for autonomy, competence and relatedness (Ryan and Deci, 2000). In the CODT, motivation is more a Courtier than a King, but a key player nevertheless inside the MEM system. From the perspective of CODT, the role of motivation in real behaviour change should be evaluated on the basis of the hard-won findings of systematic reviews and meta-analyses. Ng et al.'s (2012) metaanalysis of self-determination theory studies in health care found only low correlations: between autonomous self-regulation and mental and physical health of .06 and .11 respectively; between controlled regulation and mental and physical health of -.19 and . 09 respectively; and between amotivation and mental and physical health of -.05 and -.15 respectively. These correlations suggest
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that motivational style controls, at most, 3-4% of variance in mental and physical health. These modest empirical associations between selfdetermination theory constructs and health outcomes may, in part, be explained by methodological problems concerning the scoring of self-determination motivation. The validity of the assumed selfdetermination continuum, forming the basis of the measures employed, has not been supported by state-of-the-art psychometric analyses. In a Rasch analysis of the continuum concept, Chemolli and Gagne (2014) found strong evidence of a multidimensional factor structure rather than a continuum.
This
issue places a limitation on the use of SDT in prevention of obesity. Until these methodological issues are solved, the status of SDT remains uncertain and unclear. A RCT with SDTâ&#x20AC;&#x201C;based exercise motivation variables evaluated a behavioral weight control intervention on 3-yr weight change (Silva et al., 2009, 2011). The one-year SDT-based intervention was immediately followed up and then again 2-years later with 221 female participants. The intervention group attended 30 sessions, targeted at increasing physical activity and energy expenditure, adopting a diet consistent with a moderate energy deficit, and integrating exercise and eating patterns that would support weight maintenance. The control group received 29-sessions of general health education on the basis of several educational courses covering various topics, e.g., preventive nutrition, stress management, self-care, and effective communication skills. Treatment had significant effects on 1- and 2-yr autonomous
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regulations, 2-yr physical activity, and 3-yr weight change. Average weight loss at 12 months was -7.29% vs. -1.74% in the control group, but the intervention effect tapered off over time showing only -3.9% vs. -1.9% in the control at 36 months. The intervention produced a 2.0% greater average weight loss at 36 months than the control condition. Autonomous style motivation correlated -.31 with 3-year weight change, explaining only 10% of the variance in weight change. Unfortunately, the theoretical importance of the motivation construct has not yet been empirically established in the form of concrete health outcomes. Unless psychological theories and interventions can be cashed out in objective benefits to health outcomes, they tend to lead only to false hopes and disappointment. The role of individual motivation appears to be a modest one, one process among many within a complex multilevel system, as explicated in the CODT. The poor motivation reported by many PLWO is an obstacle to treatments and undoubtedly plays a role in the poor outcomes that are obtained. Upstream methods for obesity prevention provide rational and effective strategies for the elimination of the condition in future generations and it is on these methods that resources should be concentrated. The CODT is a motivational theory. The strong desire to satisfy wants and needs includes the fundamental desire to increase comfort (positive affect) and to reduce suffering, anxiety and depression (negative affect). The eternal struggle to maximize the former and to minimize the latter is the main drive of
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sentient
beings. The struggle between pleasure and pain is a defining feature of all living beings, the yin and yang of life itself. There can be nothing more fundamental to survival of the species.
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Seven: Prevention
To have significant impact on the obesity epidemic, effective prevention strategies must be delivered. Any long-term strategy to curtail the obesity epidemic needs to be based on effectiveness and cost-effectiveness. In this regard, upstream interventions have been shown to be significantly more effective and more costeffective than downstream ones. In agreement with many other economic reports, a recent economic analysis of the obesity epidemic concluded: â&#x20AC;&#x153;Education and personal responsibility are critical elements of any program to reduce obesity, but not sufficient on their own. Additional interventions are needed that rely less on conscious choices by individuals and more on changes to the environment and societal normsâ&#x20AC;? (Dobbs et al., 2014). The infrastructure required for individual-level psychological interventions for the two billion people with overweight or obesity far outstrips available resources. To make any real impact on the obesity epidemic, it is essential to implement upstream policies to change the environmental context that
currently promotes the
spread of obesity at all levels of society. A sea change is necessary to the food environment, to the social environment, and to the individualistic culture that promotes the blaming of victims.
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For decades psychologists have ambitiously striven to tackle problems of 'unhealthy lifestyles' using individual–level theories and therapies. This individualized treatment approach has led to the raising of false hopes, poor outcomes, and no significant improvement to population health. There is a need to change gears and raise the game to an environmental level. Pelletier et al. (2016) argue that “Environmental changes … may be slow to implement, can be very expensive, and could be stalled by industries with competing interests”. However, economic studies have demonstrated that environmental changes in the form of regulations on sugar or advertizing can generate significant revenue. Both the sugar-sweetened beverage excise tax and the elimination of the tax subsidy for advertising unhealthy food to children would lead to substantial yearly tax revenues ($12.5 billion and $80 million, respectively; see Gortmaker et al., 2015 b). The analyses of Gortmaker et al. (2015 a, b) have shown that the cost effectiveness of these preventive interventions is greater than that obtained from published clinical interventions to treat obesity. Individual approaches using social cognition models have been tried and tested for many years but outcomes have been consistently disappointing (Marks, Murray, Evans & Estacio, 2015). Lehnert et al. (2012) reviewed long-term economic findings (at least 40 years) for 41 obesity prevention interventions. Interventions were grouped according to their method of delivery, setting and risk factors targeted into behavioural (n = 21), community (n = 12) and environmental interventions (n = 8). Interventions that modified a target population’s environment, i.e.
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fiscal and regulatory measures, reported the most favourable costeffectiveness. There can be little doubt that obesity prevention requires the use of cost-effective interventions at all levels of society. For the two billion-plus individuals living today with overweight and obesity these words will not be very welcome. But it is better to face the truth than live in a dreamworld with impossible hopes and expectations. For the vast majority of obese people alive today, there will be no significant reversal. Current treatments are disappointingly weak, expensive, and, often, have unwanted side effects, especially drugs and surgery (Marks et al., 2015). The only way forward that makes sense is prevention -
to prevent new
cases, as many as possible. The emphasis should be placed on upstream approaches, preventing new floods of cases before they arrive at the point of no return. Ananthapavan, Sacks and Moodie et al. (2014) review the potential contribution of health economics in supporting resource allocation decision making for obesity prevention/treatment. They suggest that, while economic evaluations of single interventions provide useful information, evaluations that are part of a priority setting exercise provide the greatest scope for influencing decision making. They review several priority setting examples in prevention and treatment that indicate the value of policy-based (as compared with programme-based) interventions, targeted at prevention (as compared with treatment) and focused â&#x20AC;&#x153;upstreamâ&#x20AC;? on the food environment, are likely to be the most cost-effective options for change. However, they also found that methodological
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advances are necessary including the incorporation of intervention costs/benefits outside the health sector, the addressing of equity impacts, and the increased engagement of decision makers in the priority setting process. The active engagement and participation of PLWO in policybased interventions would be a productive way forward. A significant turning point could be activism spear-headed by PLWO themselves. PLWO need to raise their voices to resist their continued exploitation in the retail marketplace and in health care in creating movements of resistance. With two-thirds of US adults struggling with overweight and obesity, PLWO could be a powerful lobby and have real impact at the ballot box. Several strategies for the prevention of obesity which spring from Obesity Dyshomeostasis Theory are illustrated in Figure 8. There are many hotly debated controversies about food, diets and dieting. Different dietary interventions for obesity have been extensively explored but outcomes have been universally modest. From simple trials of a single method to complex multi-component treatments, interventions have yielded unexciting results. A discussion paper providing an upbeat economic perspective on obesity prevention listed 74 interventions across 18 groups (Dobbs et al., 2014). Weight management programmes were listed fourth in terms of estimated impact beneath portion control, reformulation and high-energy food and beverage availability. Behavioural interventions in obesity prevention and treatment have yielded disappointing outcomes. Raising false hopes among people with overweight or obesity by continuing to offer interventions that have
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such poor outcomes is a questionable practice. The report contains some helpful economic analyses but there is almost no discussion of psychological evidence on the causes or consequences of overweight and obesity. Reliance is placed on “subconscious mechanisms” illustrated by this quotation: “subconscious mechanisms change the physical activity and food and drink environments, and are therefore more likely to change behavior “ (Dobbs et al., 2014, p. 46). For “subconscious”, I think we have to read “environmental”, but the two terms cannot be used interchangeably because environmental changes described as “subconscious” in the Dobbs et al. report are invariably consciously perceived, e.g. improved labelling of foods. A psychological analysis of the the causes and consequences of overweight and obesity that yields effective interventions is absent from the Dobbs et al. report. The CODT fills that gap. Behavioural interventions in obesity prevention and treatment have yielded disappointing outcomes. Raising false hopes among PLWO by continuing to offer interventions that have such poor outcomes is a questionable practice that should be terminated. In spite of having strong motivation and significant effort, many largebodied individuals cannot achieve significant weight loss because of a hereditary component. However, people who have become obese from a slimmer baseline may have the capability to shed their weight gain and return to that baseline. Economic analysis has been applied to interventions to determine which should be prioritised. Sacks et al. (2010) compared the cost-effectiveness of two commonly proposed
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policy-based interventions in Australia: front-of-pack ‘traffic-light’ nutrition labelling (traffic-light labelling) and a tax on unhealthy foods (‘junk-food’ tax). Estimates of changes in energy intake were based on an assumed 10% shift in consumption towards healthier options in four food categories (breakfast cereals, pastries, sausages and preprepared meals) in 10% of adults. Sacks et al. (2010) concluded that such policy-based population-wide interventions offer excellent ‘value for money’. Cecchini et al. (2010)
outlined public health strategies for
chronic diseases that are closely linked to obesity. Prevention policies could generate substantial health gains while entirely or largely paying for themselves through future savings in health-care expenditures. These strategies include: health communication to improve population awareness about the benefits of healthy eating and physical activity; fiscal measures that increase the price of unhealthy food content or reduce the cost of healthy foods rich in fibre; and regulatory measures that improve nutritional information or restrict the marketing of unhealthy foods to children. Economic growth is driving increased consumption of processed, high-caloric, low nutrient foods and beverages in an environment where passive over-consumption is pervasive. A recent review of the economics of obesity concluded: “The interventions most likely to be cost-effective were the upstream interventions that targeted the environmental drivers of the obesity epidemic such as regulation related to unhealthy food and beverage advertising, front of pack nutrition labelling and taxes on unhealthy food and beverages” (Ananthapavan, Sacks, Moodie &
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Carter, 2014). In light of analyses such as those reviewed, four practical and cost-effective strategies for obesity prevention are recommended: (1) Resisting and putting a stop to victim-blaming, stigma and discrimination using anti-discrimination legislation; (2) Resisting and devalorizing the thin-ideal by enforcing truth in advertising; (3) Resisting and reducing the consumption of energy-dense, low nutrient foods and drinks; (4) Improving access to and the attractiveness of plant-based diets. These ideas are rational and feasible. However, they have yet to be implemented with the energy and commitment that is warranted in light of the scale of the obesity epidemic and the economic and environmental forces that are causing it. The following sections discuss each of the strategies in turn. Strategy 1: Anti-discrimination legislation. If we accept that a combination of genetic, epigenetic and environmental factors are the causes of obesity, it is clear that the biological and psychosocial processes regulating bodyweight are operating in the unconscious realm. PLWO do not choose an obesogenic lifestyle. It is an inevitable consequence of dyshomeostasis in response to the 'stress of life'. This fact makes any form of victim-blaming irrational and discriminatory and should be made culpable under anti-discrimination laws. Research reviewed above shows that PLWO are highly stigmatized, and that bias and discrimination are a regular occurrence. The situation has been described thus:
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Given that half the [American] population is overweight, the number of people potentially faced with discrimination and stigmatization is immense. The consequences of being denied jobs, disadvantaged in education, or marginalized by health care professionals because of one’s weight can have a profound impact on family life, social status, and quality of life. Obese individuals can suffer terribly from this, both from direct discrimination and from other behaviours (e.g. teasing and social exclusion) that arise from weight-related stigma. (Puhl and Brownell, 2004, p. 69). There has been no published evidence that negative attitudes toward PLWO is becoming less prevalent (e.g. Puhl and Heuer, 2009). The authors concluded that weight bias will remain a social injustice and public health issue, impairing the quality of life for both present and future generations of obese individuals. Weight bias exists not only in the lay population but in health care professionals specializing in obesity. Schwartz et al. (2003) used the the Implicit Associations Test (IAT) and a self-report questionnaire to assess attitudes, personal experiences with obesity, and demographic characteristics with clinicians and researchers attending the opening session of an international obesity conference (N = 389). The IAT was used to assess implicit weight bias (associating “obese people” and “thin people” with “good” vs. “bad”) and three ranges of stereotypes: lazy-motivated, smart-stupid, and valuable-worthless. The health professionals showed significant pro-thin, anti-fat bias on the IAT. In addition, participants significantly endorsed the implicit stereotypes of lazy, stupid, and worthless. The fact that professionals in clinical
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management of obesity show strong weight bias indicates “pervasive and powerful stigma” (Schwartz et al., 2003). There is little reason to think that anti-fat stigma will have lessened over the last 12 years. In the US, discrimination is prohibited under public laws enacted by Congress. For example, federal funding of research is granted only if there is no discrimination on the basis of race, color, national origin, religion, gender, or physical or mental disabilities: “...no person in the United States shall, on the grounds of race, color, national origin, religion, gender, or physical or mental disabilities, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any program or activity (or, on the basis of sex, with respect to any education program or activity) receiving Federal financial assistance”. There is no mention here of overweight or obesity. Currently, only one state (Michigan) and several localities across the US (San Francisco and Santa Cruz in California, Washington, DC, Madison, Wisconsin, Urbana, Illinois, and Binghamton, New York) have laws prohibiting weight discrimination, as a protected category within existing civil and human rights statutes. Yet online surveys conducted in 2011, 2012 and 2013 indicate that there is strong, consistent support for policies prohibiting weight discrimination in the US (Suh et al., 2014). Similarly, in Europe, the EU Equal Treatment Directives implements the principle of equal treatment between men and women in EU Labour Law and, in the UK, the UK Equality Act of
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2010 provides an anti-discrimination law protecting workers against discrimination in employment on grounds of religion or belief, sexual orientation and age. It requires equal treatment in access to employment as well as private and public services, regardless of the protected characteristics of age, disability, gender assignment, marriage and civil partnership, race, religion or belief, sex, and
sexual orientation. Once again, there is no
mention of overweight and obesity. Without legislation, there is little prospect that discrimination against, and stigmatization of, PLWO will change.
There is an
immediate need to develop specific anti-discrimination legislation to protect people with obesity and improve their quality of life. Antidiscrimination laws will help to eliminate one of the primary sources of discontent responsible for the causation of obesity. Strategy 2: Resisting and Devalorizing the Thin-Ideal. There is an immediate need for legislation to control the prominent use of images representing the thin-ideal. As has been the case with tobacco advertising for many years, governments need to legislate to restrict presentations in the media, both print and electronic, of prominent display on magazine covers and in advertisements of abnormally thin models. In the US, H.R. 4341, also known as the Truth in Advertising Act, is being considered by Congress. The Truth in Advertising Act of 2014: â&#x20AC;&#x153;Directs the Federal Trade Commission (FTC) to submit a r eport to Congress that contains: (1) a strategy to reduce the use, in advertising and other media for the promotion of
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commercial products, of images that have been altered to materially change the physical characteristics of the faces and bodies of the individuals depicted; and (2) recommendations for a risk-based regulatory framework with respect to such use. Requires the FTC to solicit input from external stakeholders and experts including, to the extent practicable, from: (1) stakeholders that are geographically and culturally diverse; and (2) experts from physical and mental health, business, and consumer advocacy communities.” If the thin-ideal is ever going to be replaced by a more representative body shape, then similar legislation is needed throughout the world. Even under existing employment legislation, the employment of thin models to the exclusion of models with average of large body size could be considered illegal under equal opportunities legislation. If attempts to control the publication of images of thin models in print and electronic media do not succeed, then legislation will be required to enforce plain covers on fashion magazines. The Québec Charter for a Healthy and Diverse Body Image (La Charte Quebecoise Pour Une Image Corporelle Saine et Diversifiée, also referred to as 'La Chic') from 2009 defined seven avenues for action: “1. Promote a diversity of body images, including different heights, proportions, and ages 2. Encourage healthy eating and weight control habits 3. Discourage excessive behavior with respect to weight loss or appearance modification. 4.
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Refuse to subscribe to esthetic ideals based on extreme slimness 5. Remain vigilant and diligent in order to minimize the risks of anorexia, bulimia, and unhealthy concerns about weight. Act as agents of change in order to promote healthy and realistic practices and images regarding the body 7. Promote the Québec Charter for a Healthy and Diverse Body Image to our partners, clientele, and colleagues while actively adhering to and respecting these principles.” An evaluation of the Québec Charter for a Healthy and Diverse Body Image was published by Gauvin and Steiger (2014). They examined the population reach, acceptability, and perceived potential of the initiative six months after the Charter’s launch. They surveyed 1003 Québec residents aged 18 years or older about their knowledge of the Charter, their willingness to adhere to it, and their perceptions of its potential. Around 35% of respondents recognized the Charter, 34% were very favorable toward personally adhering to the Charter and 33% perceived the Charter as having high potential to sensitize people to negative consequences of disordered eating. The authors concluded that Charter reached a substantial portion of adults and is viewed as acceptable and potentially influential. Longer term outcomes need to be assessed in a larger-scale study. In Australia in 2009 a Voluntary Industry code of Conduct On Body Image was published. Organisations that signed up to this code of Conduct agreed to abide by the following principles: Positive content and messaging Use positive content and messaging to support the
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development of a positive body image and realistic and healthy physical goals and aspirations among consumers. Realistic and natural images of people Should not use digital technology in a way that alters images of people so that their body shape and features are unrealistic or unattainable through healthy practices. Make consumers aware of the extent to which images of people have been manipulated. Healthy weight models Use models that are clearly of a healthy weight. Appropriate modelling age Only use people aged 16 years or older to model adult clothes or to work or model in fashion shows targeting an adult audience. Fashion retailers supporting positive body image Stock a wide variety of sizes that reflects demand from customers. (Australian Government, 2009). Voluntary codes are almost never effective. To be effective, policy interventions need to mandate changes. In 2015, France passed legislation to outlaw excessively thin fashion models and start levying fines on agencies and fashion houses that continue to hire them. The country is joining Israel (which passed similar laws in 2013) in taking measures to curtail the culture of super-skinny models on the catwalk and in advertising campaigns. Under this new legislation, models need to present medical proof that they are healthy enough to be hired for a job. Fashion house and agency professionals that overlook the new ruling could face up to
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$82,000 in fines or even six months in prison. The move by France, a world leader in the fashion and luxury industries worth tens of billions of euros, is likely to have an international impact because many models from other countries such as the US and UK travel to work in France. Other countries, such as Italy and Spain, rely on voluntary codes of conduct to prevent exploitation of excessively thin models. The French legislation was driven by a campaign against, not obesity, but anorexia (The Guardian, 2015). In 2010, Isabelle Caro, an anorexic 28-year-old former French fashion model, died after posing for a photographic campaign to raise awareness about the illness. In addition, any re-touched photo that alters the bodily appearance of a model for commercial purposes must carry a message stating it had been manipulated. A second measure means that any website inciting a reader to "seek excessive thinness by encouraging eating restrictions for a prolonged period of time, resulting in risk of mortality or damage to health" will face up to a year in prison and fines of up to 100,000 euros. Other challenges to the thin-ideal involve innovative curricula in education. Australia adopted the â&#x20AC;&#x153;Revised Australian Curriculum: Health and Physical Education: Foundation to Year 10â&#x20AC;? (Australian Curriculum, Assessment and Reporting Authority, 2013) that has included body image as a topic in the curriculum and supported media literacy resources in the analysis of body image influences within education. At a more downstream level, school-based interventions can be offered to enable youth and women to resist pressures towards self-objectivation whatever its
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source (Tylka and Augustus-Horvath, 2011). Health educators can find themselves struggling with the same problems of body image as their students. College health professionals can be creative in making plans of action for reducing the negative effects of such influences. Discussions of body image can be incorporated into health curricula and classes, focusing research on intervention, and using advocacy to initiate change at the societal level (Rasberry, 2008). In educational settings, eating disorders prevention programmes can be incorporated into health studies curricula using computer-based interactive procedures (e.g. Graff Low et al., 2006). It has been found that time spent on the Internet using social media such as Facebook is significantly related to internalization of the thin ideal, body surveillance, and drive for thinness (Tiggemann and Slater, 2013). Social media such as Facebook can also be used to critique and resist cultural stereotypes such as the thin-ideal. Strategy 3: Resisting and reducing the consumption of energy-dense, low nutrient foods and drinks. It was noted above that an inverse relationship exists between energy density of foods (kilojoules per gram) and their energy cost (dollars per megajoule). In addition, the inverse relationship between affordability and healthfulness helps to explain why the highest rates of obesity and diabetes are found among minorities and the working poor. With these facts in mind, it behoves government to enact legislation to make fruit and vegetable (F/V) intake more affordable and fast processed foods and beverages
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less desirable. The imposition of a sugar, fat or salt tax on people who are already hard-pressed making healthy food purchases would be unfair and only make matters worse unless carefully targeted at specific products that are known to be linked to overweight and obesity such as soda drinks. Sugar consumption is a major factor in childhood obesity, and sugar-sweetened soft drinks are the single biggest source of dietary sugar for children and teenagers and sugar-sweetened soft drinks are a major factor in the prevalence of childhood obesity. In its Budget 2016 the UK government announced a new soft drinks industry levy targeted at producers and importers of soft drinks that contain added sugar. The levy, which will become effective from 2018, is designed to encourage companies to reformulate by reducing the amount of added sugar in the drinks they sell, moving consumers towards lower sugar alternatives, and reducing portion sizes. If producers change their behaviour, as is to be expected, then they will pay less tax. The levy is expected to raise £520 million in the first year. In England, revenue from the soft drinks industry levy will be used to double the primary school physical education and sport premium from £160 to £320 million per year to help schools support healthier, more active lifestyles. The sugar levy will also provide £10 million funding a year to expand breakfast clubs in up to 1,600 schools to ensure more children have a nutritious breakfast as a healthy start to their school day. A more comprehensive levy could also be considered in which manufacturers are levied for formulations that contain any amount
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of sugar, salt or trans fat. An 'Unhealthy Commodities Tax' (UCT) on producers and suppliers would be proportionate to the total content of unhealthy ingredients. This tax could be rationally computed based on known contents of all foods and beverages available for sale, not simply soda drinks. The UCT would be based on the known unhealthy contents of sugar, salt and trans fats. For any product, the total weight in grams of saturated fat, trans fat, sugar and salt could be summated to give the total weight for the unhealthy content (UC) using the formula: UC = grams of saturated fat + grams of trans fat + grams of sugar + grams of salt A list of ten products that have been hypothetically subjected to UCT is presented in Table 3. For example, a McDonalds Big Mac containing 10 grams of fat, 9 grams of sugar and 0.2 grams of salt, has a total UC of 19.2 grams. Charging one penny per gram generates a UTC of 19 pence, 7% of the price of a Big Mac in the UK (January 2015 prices). To make the system as fair as possible, UTC should be divided equally between producers and suppliers. In the case of the Big Mac, McDonalds would pay 3.5% of the sale price and the retail franchisee would pay 3.5% also. The imposition of UTC would incentivise suppliers to reformulate their products towards the lowest possible levels of fat, sugar and salt. Retailers would be equally incentivised to switch to less unhealthy products. Consumers would be given a healthier set of options to take home
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to their tables. In the UK, with a food and drinks market worth around ÂŁ100 billion, the revenue from UTC is estimated to be in the range of ÂŁ510 billion.
Revenues from UTC could be paid directly into two
areas: (1) To fund the National Health Service to allay costs of treating patients with obesity and related conditions such as diabetes, metabolic syndrome and cancers; (2) To subsidise the production of organic F/V with payments to growers and sellers
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to enable lower retail prices of organic F/V. The use of a UTC tax for these purposes would be a fair use of resources because a share of the profits from sale of unhealthy commodities would contribute proportionately to (A) the resulting health service costs; (B) improving the diet of consumers towards higher F/G intake. Legislation to introduce UTC would be a significant step towards reducing inequities and the eradication of the obesity gradient. Strategy 4: Improving access to plant-based diets. On behalf of the Union of Concerned Scientists, Boucher et al. (2012) argued that a diet shift from beef toward chicken would greatly reduce the pressure on land and the resulting pressure for deforestation. It would also have health benefits, particularly in developed countries where beef consumption is already at levels leading to heart disease, cancer, and other illnesses. Other authorities have been recommending a switch to a plant-based diets (e.g. Campbell & Campbell, 2005), a recommendation that is well supported by epidemiological studies. High F/V intake decreases risk of cardiovascular disease and of certain cancers, mainly of the digestive system, and is inversely linked to body weight and fat mass. In comparison with high sugar and high fat foods, F/V intake contributes to the prevention of weight gain among overweight individuals (Guillaumie,Godin & VĂŠzina-Im, 2010). High F/V intake is associated with better health, especially among those who consume at least five servings per day (Heimendinger, Duyn, Chapelsky, Foerster, Stables, 1996;
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Stables,
Subar & Patterson, 2002). Some countries such as
Canada and Australia have considered increasing the recommended F/V intake to at least seven or eight servings a day. He, Nowson, Lucas and MacGregor (2007) reported the finding from a metaanalysis that increased F/V consumption is related to a reduced risk of coronary heart disease (CHD) Compared with individuals who had less than 3 servings/day of F/Vs, the pooled relative risk of CHD was 0.93 for those with 3–5 servings/day and 0.83 for those with more than 5 servings/day. Boeing et al. (2012) reviewed the protective effects of increased F/V intake on a wide range of conditions, that included obesity, type 2 diabetes mellitus, hypertension, CHD, stroke, cancer, chronic inflammatory bowel disease, rheumatoid arthritis, chronic obstructive pulmonary disease, asthma, osteoporosis, eye diseases, and dementia. The authors concluded: “from a scientific point of view, national campaigns to increase F/V (intake) are justified. The promotion of F/V (intake) by nutrition and health policies is a preferable strategy to decrease the burden of several chronic diseases in Western societies” (Boeing et al., 2012). Meats are high in energy and fat and it is not surprising that meat consumption (MC) is associated with overweight and obesity. Wang and Beydoun (2009) analysed data collected in the 1999– 2004 National Health and Nutrition Examination Survey (NHANES) to test the associations between MC and adiposity measures controlling for potential confounders. Those who consumed more meat had a significantly higher daily total energy intake, for example, those in the upper vs bottom quintiles consumed around
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700 more kcalâ&#x20AC;&#x2030; per day. Regression models showed consistent dose-related positive associations between MC and BMI, waist circumference, obesity and central obesity. Reducing the amount of meat in one's diet can be an effective dietary intervention for PLWO. The most extreme forms of this diet are the vegetarian and vegan diets. Vegetarian diets include eggs and/or dairy but no other foods derived from animal sources. Vegan diets exclude all animal-based foods. In addition to improved health including weight loss, making the switch to a plant-based diet can be driven by ethical beliefs against animal cruelty and by concerns for the environment. Recent scientific evidence has indicated that a vegetarian diet reduces the risk of most contemporary diseases and that vegetarianism is being increasingly accepted owing to health concerns and ethical, environmental, and social issues including the need for a sustainable nutrition. A meta-analysis with 120,000 participants reported a 29% lowered risk of death from cardiovascular disease in vegetarians and an 18% lower incidence of cancer (Huang, Yang, Zheng, Li, Wahlqvist and Li , 2012). Vegetarians also have lower risk of hospitalization or death from ischemic heart disease (Crowe, Appleby, Travis and Key, 2013), lower risk of hypertension (Pettersen, Anousheh, Fan et al., 2012; Yokoyama, Nishimura, Barnard et al., 2013), lower risk of developing MS (Rizzo, Sabate, Jaceldo-Siegl et al., 2011), and lower risk of some cancers than meat eaters. In a systematic review of vegetarian diets and glycemic control
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in diabetes vegetarian diet was associated with a significant reduction in HbA1c [â&#x2C6;&#x2019;0.39%] and a non-significant reduction in fasting blood glucose concentration compared with consumption of comparator diets (Yokoyama, Barnard, Levin and Watanabe, 2014). Yokoyama et al. concluded that consumption of a vegetarian diet is associated with improved glycemic control in type 2 diabetes suggesting that a plant-based diet can significantly improve blood sugar levels and potentially leave patients free of the disease. Although not compared directly in the analysis, the findings suggest relief from diabetes symptoms with a vegetarian diet are superior to those expected from drug therapy.
Other
studies showed that vegetarians and fish eaters have a lower risk of cancer compared to meat eaters (Key, Appleby, Spencer et al., 2009), lower risk of diverticular disease compared to meat eaters or fish eaters and vegans have an even lower risk (Crowe, Appleby, Allen and Key, 2011). Vegetarians, especially vegans, have a lower risk of developing type 2 diabetes (Tonstad, Butler, Yan and Fraser, 2009; Tonstad, Stewart, Oda et al., 2013). However, vegans require dietary supplements of vitamin B12, B6, D and iodine.In light of the evidence concerning plant-based diets as a diet of choice for PLWO, the ability to change to a vegetarian or vegan diet, and to maintain the change, is a topic of some importance. On current evidence, vegetarian and vegan diets, with increased intake of F/V and reduced meat consumption, provide a sustainable and effective means for achieving healthful nutrition and a significantly beneficial method of reducing adiposity. For many people, however, the pricing of food requires rebalancing to
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make a diet of healthy plant based foods as affordable as a diet that concentrates on meat and dairy. The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) is the largest food supplement programme in the US, serving around nine million participants each year (Coleman-Jensen, Gregory & Singh, 2014). Eligibility is based on nutritional need and income. Eligible participants receive five main benefits: (I) Supplemental food cheques or an electronic benefit card are issued to programme participants enabling them them to purchase nutritious food at approved stores. The average monthly benefit in 2014 was $43.26. (ii) Formula vouchers. (iii) Nutrition education. (iv) Access to healthcare and other social services.(v) Breastfeeding support. In addition to the above five benefits, a system like the WIC provides an opportunity to improve F/V for millions of people. Trials have shown positive results. Herman, Harrison, Afifi and Jenks (2008) tested the effectiveness of a subsidy for fruits and vegetables to the WIC. Women who enrolled for postpartum services (n=602) at three sites in Los Angeles were assigned to an intervention (farmersâ&#x20AC;&#x2122; market or supermarket, both with redeemable food vouchers) or control condition (a minimal nonfood incentive). Interventions were carried out for 6 months, and participantsâ&#x20AC;&#x2122; diets were followed for an additional 6 months. Participants increased their F/V consumption and sustained the increase 6 months after the intervention. Farmersâ&#x20AC;&#x2122; market participants showed an increase of 1.4 servings per 4186 kJ (1000 kcal) of consumed food from baseline to the end of intervention
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compared with controls, and supermarket participants showed an increase of 0.8 servings per 4186 kJ of consumed food. In 2009, WIC added a F/V voucher to WIC food packages. Following the changes to the WIC food package, Whaley et al. (2012) found that consumption of whole-grain food increased by 17.3%, a 51% increase over baseline. In addition, caregivers and children who usually consumed whole milk decreased by 15.7 and 19.7%, respectively, a 60%-63% reduction over baseline. Small but significant increases in F/V consumption were also reported. The investigators concluded that the federal policy changes to WIC had the intended effect of increasing consumption of the prescribed food items. In support of this finding, Zenk et al. (2014) used a quasi-experimental design to determine whether F/V prices at WIC vendor stores decreased after the policy revision in seven Illinois counties. Results suggested that the WIC policy revision contributed to reductions in F/V prices. In light of these and other findings, there can be little doubt that adding fresh fruits and vegetables to WIC food packages would result in increased access to F/V consumption. Following the WIC model, legislation should be considered in every state and country to improve F/V intake.
As suggested above, proceeds from the
UCT could be used to subsidise the organic production of F/V with payments to growers and sellers to enable lower retail prices of organic F/V. Interventions to increase access and affordability of F/V would help to slow the obesity epidemic.
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Conclusions The four obesity prevention strategies described above have the potential to reduce obesity prevalence in future generations. These strategies are certainly theoretically necessary, but only experience can show whether they are sufficient. Unfortunately this author's confidence in their potential effectiveness is unlikely to be matched by the governing authorities' willingness to legislate them into action. Powerful lobbying from the captains of industry will always argue for voluntary agreements, as was the case for tobacco control. Yet experience proves that mandatory changes can and do yield significant improvements in public health.
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Eight: Questions
Obesity Dyshomeostasis Theory proposes that weight gain is fostered by a Circle of Discontent which consists of four causally interrelated processes: body dissatisfaction, negative affect, overconsumption and obesity. The theory provides a new scientific explanation of obesity with a strong empirical evidence-base and has a well-defined neurobiological foundation. In light of the theory, strategies for the prevention of future cases of obesity have been proposed. In this chapter, I discuss a few of the interesting issues raised by recent commentators on the CODT (Annunziato & Grossman, 2016; Brindal & Wittert, 2016; DiClemente & Delahanty, 2016; Markey et al., 2016; Pelletier et al., 2016; Piko & Brassai, 2016; Roosen & Mills, 2016). Avenues with potential for further investigation are explored. Educational Settings Drawing on the framework of the CODT, Annunziato and Grossman (2016) describe research in two domains, victimblaming and devalorizing the thin-ideal. Annunziato and Grossman suggest that university-based clinical health psychologists are uniquely positioned to implement large-scale approaches that have shown promise in addressing core issues in the CODT.
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Annunziato and Grossman cite examples of research that include a “Social and Emotional Learning” curriculum in Sweden that demonstrated decreases in victimization (Kimber et al., 2008) and the “Body Project” in the US that has produced reductions in eating disorders, in thin-ideal internalization, body image dissatisfaction and negative affect in female students (Stice et al., 2011, 2012, 2013) and an internet-based programme that demonstrated large weight gain prevention effects (Stice et al., 2014). Annunziato and Grossman (2016) propose more extensive use of both systemic and individual interventions with adolescents and young adults in school settings. For example, large-scale programs in secondary schools and universities could be designed to bring about culture change. A school-based programme is described by Tran et al. (2014) based in the Canadian province of Alberta. Fung et al. (2012) demonstrated the feasibility and effectiveness of a school-based program in preventing childhood obesity, the Alberta Project Promoting active Living and healthy Eating in Schools (APPLE Schools). The
intervention involved a full-time School Health
Facilitator in each of 10 schools for implementing healthy eating and active living policies, practices and strategies while engaging stakeholders, including parents, staff and the community. The Facilitators contributed to the schools' health curriculum, and organized activities such as cooking clubs and healthy breakfast, lunch and snack programs, after school physical activity programs, walk-to-school days, community gardens, weekend events and circulated newsletters. By 2010 the students' eating habits and
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physical activity levels at APPLE Schools had improved significantly while obesity prevalence had declined relative to their peers attending other Albertan schools. Other comprehensive school-based programs have achieved similarly positive results (Greening et al., 2011; Khambalia, 2012; Verstraeten et al., 2012; Veugelers & Fitzgerald, 2005). Ideally, education about and training of healthy eating habits and regular physical activity will become a part of every school curriculum universally. In combination with Strategy 2 described in the previous chapter, the Body Project provides an effective intervention for resisting and combatting the thin-ideal in educational settings everywhere. Are national governments everywhere prepared to put their money where their mouth is and invest in effective state-wide educational programmes to prevent obesity? Couples and Families Markey et al. (2016) referred to the role of social relationships in couples' eating patterns. They point out that romantically-involved partners appear to be an especially important and understudied factor in eating behaviors, body image, and obesity risk. In line with Markey et al.'s (2016) ideas, there is certainly evidence from studies on marital couples which supports the suggestion. Jaremka et al. (2015) investigated the influence of the quality of marital relationships on appetite regulation using a double-blind, randomized crossover trial. Both members in 43 couples were invited to eat a standardized meal at the beginning of two visits. Observational recordings of marital conflict were employed to
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assess marital distress. Samples of GH and leptin were taken premeal and post-meal at 2, 4, and 7 hr. The findings suggested that people in more distressed marriages have higher post-meal GH and a poorer quality diet than those in less distressed marriages, but only among participants with lower BMI.
Ghrelin and diet
quality may provide connecting, causal links between marital distress and its negative health effects (Jaremka et al., 2015). Children growing up in disharmonious environments, whether caused by socioeconomic disadvantage or other factors, are exposed to a variety of detrimental experiences including parental frustrations, relationship discord, lack of social support and cohesion, negative belief systems, unmet emotional needs and general insecurity. These stressful experiences increase the risk of psychological and emotional distress, including low self-esteem and self-worth, negative emotions, negative self-belief, powerlessness, depression, anxiety, insecurity and a heightened sensitivity to stress (Hemmingsson, 2014). All of these processes push and pull a young person towards the Circle of Discontent. The consequences can be lifelong comfort eating, excessive use of tobacco, alcohol and other drugs that ultimately can be highly detrimental. With parents who are already inside the COD, then youngsters are COD-prone themselves, and so the COD travels through the generations. The cross-generational perspective on CODT warrants in-depth investigation. Governments need to invest in parenting with economic reforms designed to reduce the stress levels that prevail in a large section of the population. They know what is necessary, but have they the will to do it?
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'Allostasis'? In another commentary, Brindal and Wittert (2016) suggest the importance of the constructs of 'allostasis', coping style and habituation that need to be considered as additions to the COD model. They argue that the incorporation of these elements into the Obesity Dyshomeostasis Theory could help to “expand its explanatory power and associated avenues of intervention”. Furthermore they suggest that a meaningfully approach to the obesity epidemic and associated chronic disease will require “policy and regulation as well as targeted behavioural strategies aiming to reduce allostatic load”. While appreciating these comments, in this author's opinion however, the concept of 'allostasis' is misguided and adds nothing to the CODT which is founded on the concept of homeostasis described by Cannon (1932). The concepts of 'allostasis' and 'allostatic load' appear to be based on a misunderstanding of Cannon's original concept of homeostasis that covers all of the functions that proponents of 'allostasis' wish to attribute to it. In coming to this conclusion, I am following and concurring with the critical analysis of 'allostasis' provided by Day (2005).
In addition, the construct of allostasis
does not help us to better define stress. Day (2005) provided a helpful précis of the 'allostasis theory' in the following terms; McEwen and Wingfield (2003) wrote: “(the term) stress will be used to describe events that are threatening to the individual and elicit physiological and behavioural responses as part of allostasis in addition to that
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imposed by the normal life cycle'... They propose, in effect, that stress is just one type of challenge that can activate … allostatic (or, as I prefer, homeostatic) responses. Accordingly, we can summarise their position as follows: life is a series of challenges; some are part of the normal life cycle; some can be described as stressors; all of these challenges must be met, i.e. homeostasis must be maintained; the process of maintaining homeostasis (a process they would refer to as allostasis) involves wear and tear (which they refer to as allostatic load) that can impact adversely on health. This re-statement of McEwen and Wingfield’s thesis may seem banal but reading it with the bracketed words eliminated will demonstrate that understanding their thesis does not require the adoption of allostasis terminology. The critical question that remains then is this: does the concept of allostasis help us to better define stress? I suggest that the answer is 'no'” (Day, 2005, p. 1198). Diverse Bodies In discussing obesity stigmatisation, Roosen and Mills (2016) suggest the need for a cultural shift “not only to reduce thin valorization, but also to promote social acceptance of diverse bodies, including bodies that are traditionally understood as unattractive, unhealthy, and unproductive (i.e., disabled and/or obese).” Roosen and Mills (2016) suggest that this cultural shift is already underway, valorising a “fit” ideal body instead of a thin or
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muscular one (Musolino et al., 2015). Homeostasis and dyshomeostasis are evident in a diverse array of life circumstances and conditions (see Table 4 ). Roosen and Mills rightly draw attention to the broader context in which cultural stereotypes and assumptions are a negative influence on human well-being. Behavioural homeostasis occurs in a variety of ways including coping strategies, compensatory actions, life identity projects and an infinite array of sophisticated adaptations to illness, injury and life events. There are many potential areas for further investigation of the cultural roots of stigmatization. Of key significance to stigmatisation is the plain visibility of obesity, gigantism, dwarfism and, in many instances, disfigurement. The degree of stigmatisation may be influenced in part by the perceived self-responsibility for the condition. Gigantism, dwarfism and many types of disfigurement are genetic and unavoidable. On the other hand, obesity is often viewed as a controllable, changeable 'lifestyle choice'. Hopefully, the inaccuracy of this simplistic and ignorant portrayal has been thoroughly debunked in earlier sections of this book. The social perception that obese people can consciously choose to lose weight if they want to, but fail to do so through laziness, 'weakness', or lack of 'will-power', helps to explain the strong stigmatisation of obese people in modern society (Backstrom, 2012). Roosen and Mills rightly draw attention to the widespread existence of stigmatization across people living with disablement of diverse kinds. Programmes are needed to educate young people about the detrimental influences of stigmatization and to activate resistance against it.
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Spirituality Homeostasis? Piko and Brassai (2015) make a case for spiritual balance as a form of homeostasis.
They contend, correctly I believe,
that
existential attitudes are closely related to â&#x20AC;&#x153;identity formation, moral development, value-related attitudes, personal goals, and lifestyle choicesâ&#x20AC;?. Having meaning in life is associated with engagement in health-promoting behaviors and the avoidance of health-risking behaviors, such as obesity and eating disorders. Along with physical, cultural, psychosocial and economic needs, a definition of health may also specify spiritual needs, not simply the absence
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of illness (Marks et al., 2015, p. 5). Piko and Brassai (2016) discuss the meaning-making model of Park (2010) that proposes that people’s perceptions may contribute to content/discontent with life, body and the world. Park (2013) states: “According to the Meaning Making Model, the degree to which one perceives one’s illness as discrepant from one’s global beliefs, such as those regarding identity (e.g., I live a healthy life style) and health (e.g., living a healthy lifestyle protects people from illness), and global goals (e.g., desire to live a long time with robust health) determines the extent to which the illness is distressing” (p. 43). The Meaning Making Model includes the assumption that a discrepancy exists between global beliefs and identity that produces distress. In some cases, those beliefs are spiritual in nature. However, primary sources of research on spirituality are not all supportive of the model proposed by Park (2013). For example, the existential significance of meaning and purposefulness had previously been strongly advocated by Viktor E Frankl (1959) and, later, in the Salutogenic Theory of Aaron Antonovsky (1979, 1987) yet neither Frankl (1952) nor Antonovsy is referenced by Park (2010, 2013). We must never forget what Frankl said about the prisoners living in concentration camps: “Every man was controlled by one thought only: to keep himself alive for the family waiting for him at home, and to save his friends” (Frankl, 1959). In describing the inmates' dream life, he stated: “What did the prisoner dream about most frequently? Of bread, cake, cigarettes, and nice warm baths. The lack of having these
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simple desires satisfied led him to seek wish-fulfilment in dreams.” In another place, Frankl describes his ultimate realisation, that it is love that satisfies a person's needs for meaning: “A thought transfixed me: for the first time in my life I saw the truth as it is set into song by so many poets, proclaimed as the final wisdom by so many thinkers. The truth —that love is the ultimate and the highest goal to which man can aspire. Then I grasped the meaning of the greatest secret that human poetry and human thought and belief have to impart: The salvation of man is through love and in love. I understood how a man who has nothing left in this world still may know bliss, be it only for a brief moment, in the contemplation of his beloved..."Set me like a seal upon thy heart, love is as strong as death."“ No mention is made here of spirituality. Frankl (1952) asserted what he called “the will to meaning”: man's search for meaning as the primary motivation in his life. The GTW posits causal reciprocal relationships between subjective well-being and life satisfaction (Marks, 2015a; Marks, Murray, Evans & Estacio, 2015). In many respects, the two concepts overlap. Empirical studies suggest the existence of strong and stable associations between meaning in life and subjective well-being (Zika & Chamberlain, 1992). People who experience their lives as meaningful tend to be more optimistic and self-actualized
(Compton et al., 1996), experience more self-
esteem (Steger et al., 2006) and positive affect (King et al., 2006), as well as suffering less depression and anxiety (Steger et al., 2006) and less suicidal ideation (Harlow et al., 1986). The
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Salutogenic Theory of Antonovsky emphasized the relationship between meaning, purpose in life and positive health outcomes (Eriksson & LindstrĂśm, 2006). For many people, spiritual experience is a source of great meaning. However it must be stated that spiritual beliefs and experiences are far from universal. To quote one statistic, in the region of 500-750 million people worldwide have no religious or spiritual beliefs and are living as declared atheists (Zuckerman, 2009).
In homeostasis the organism actively strives to actively
reduce the discrepancy between an optimum level of a quantity or quality and its current state. While many people certainly strive for meaning, and may feel that they lead 'empty lives', there is no evidence of an optimum level or a homeostatic mechanism for spirituality. Yet there may be other subjective elements of human experience that warrant a homeostasis hypothesis. The GTW, attachment style has been given a primary developmental role (Figures 5, 6 and 8; Marks, 2015a; Marks et al., 2015). A core part of attachment to a parent or significant other is the emotion of love. One striking discovery by Frankl was the significance of love in people on the brink of death who were suffering from extreme food deprivation and cruelty. Frankl concluded his work with the statement that â&#x20AC;&#x153;The salvation of man is through love and in loveâ&#x20AC;?. In this light one feels entitled to ask whether love itself is a fundamental need, akin to the need for sustenance by food and drink? If so, could it too be regulated by a combination of homeostasis and hedonic reward? Clues offered by literature, music and the arts suggest the answer may be 'Yes'. Are 'love
145
sickness', loss of love and the pain of rejection, not all forms of 'love dyshomeostasis', and its inverse, the joy of love regained, a form of successful homeostasis?
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Nine: Conclusions 1) Health is regulated by homeostasis, a property of all living things. Homeostasis maintains equilibrium at set-points using feedback loops for optimum functioning of the organism. Long-term disruptions of homeostasis or 'dyshomeostasis' arise through genetic, environmental and biopsychosocial mechanisms causing illness and loss of well-being
including obesity, the
addictions, and chronic conditions. 2) Obesity dyshomeostasis is associated with a selfreinforcing activity of a vicious Circle of Discontent in which hedonic reward overrides weight homeostasis in an obesogenic and chronically stressful environment. Over-consumption of processed, high-caloric, low-nutrient foods, combined with stressful living and working conditions, have caused loss of equilibrium, overweight and obesity in more than two billion people. 3) The prevalence of obesity is higher in women and lowincome groups who are more exposed to chronic stress and low purchasing power including some ethnic minority groups.
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4) Research on different diets suggests that a plant-based diet containing low amounts of sugar, little or no red meat and the minimum of fats promotes weight-loss and prevents obesity, diabetes, metabolic syndrome, coronary heart disease, and cancer. A vegan diet with no meat, fish or dairy is especially antiobesogenic. 5) The 'thin ideal' pervades popular culture with narratives and images of thinness. This influence has an entirely negative effect on youth the world over. 6) Discrimination against people who are overweight or obese causes stress and socio-economic disadvantage. Approaches to the epidemic that invoke a narrative of 'blame-andshame' exacerbate the problem. There are very few people who deliberately become obese through conscious effort or who would not like to avoid it if they possibly could. 7) Homeostatic imbalance in obesity includes a 'Circle of Discontent' (COD) a system of feedback loops linking weight gain, body dissatisfaction, negative affect and overconsumption. This homeostatic COD theory is consistent with a large evidence-base of cross-sectional and prospective studies. 8) A preliminary model suggests that obesity dyshomeostasis is mediated by the prefrontal cortex, amygdala and HPA axis with signalling by the peptide hormone ghrelin, which
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simultaneously controls feeding, affect and hedonic reward. 9) The totality of evidence within current knowledge suggests that obesity is a persistent, intractable condition. Prevention and treatment efforts targeting sources of dyshomeostasis provide ways of reducing adiposity, ameliorating addiction, and raising the quality of life in people suffering chronic stress. 10) Vigorous and uncompromising Governmental actions are required, independent of corporate interests, at all levels of society to reduce the prevalence of obesity and related conditions. A four-armed strategy to halt the obesity epidemic is necessary. 11) T h e r e i s a n i m m e d i a t e n e e d t o e n a c t a n t i discrimination legislation to protect people with obesity and improve their quality of life. Anti-discrimination laws are necessary to eliminate one of the primary causes of obesity which fuels the Circle of Discontent. PLWO need legal protection from discrimination which has been shown to be detrimental to the mental health of the victims of obesity. 12) Legislation to enforce a mandatory code of practice is needed to resist and devalorize the thin-ideal. Precedents have been set in Israel and France to ban models with extremely low BMI, examples which should be followed in all countries. The
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retouching of pictures in fashion magazines to make the human subjects appear slimmer or more attractive should be controlled. Consumers should be informed when images of people have been manipulated. 13) Generic legislation is necessary to curb the widespread consumption of energy-dense, low nutrient foods and drinks. Mexico, France, Finland and Hungary and, most recently, the UK have set charges for a levy on sugary drinks, a step in the right direction. More generic taxation is necessary to incentivize producers and retailers to reformulate products. An 'Unhealthy Commodities Tax' which would yield revenue and improve the diet of a large segment of the at-risk population. 14)
Improving the access to plant-based diets is an
effective strategy for producing weight loss. The example of the WIC in the US indicates that increasing access to fruit and vegetables has a positive effect on food consumption towards a healthier diet. Following the WIC model, legislation should be considered in every state and country to improve F/V intake. Proceeds from a UCT could be used to subsidise the organic production of F/V with payments to growers and sellers to enable lower retail prices of organic F/V. Interventions to increase access and affordability of F/V would help to slow the obesity epidemic. 15) Huge resources have been invested on the quantitative monitoring of the obesity epidemic and on the treatment of PLWO.
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The major part of future investment should be re-directed towards the containment and control of the epidemic by legislating strategies for obesity prevention as was previously the case in tobacco control. No more kowtowing to industry. Let's cease the â&#x20AC;&#x153;shock-horrorâ&#x20AC;? narrative of obesity at all levels of society and replace it by concrete actions.
We know what is
required. Can our national governments show the necessary leadership and do what is necessary? The survival of the planet and the human race requires nothing less.
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The Author David F Marks, PhD, has published 25 books and 200-plus scientific articles. His best-selling titles include The Psychology of the Psychic (1980, 2000) and Health Psychology. Theory, Research & Practice (2015), currently in its 4th edition. Thousands have successfully given up smoking with his self-help methods for quitting (An Easier Way to Quit Smoking, 1993; Overcoming Your Smoking Habit, 2005; Give Up Smoking Now, in press). David is the editor of the Journal of Health Psychology and Health Psychology Open.
Website: www.davidfmarks.com Email: david@davidfmarks.com Twitter: @newhealthpsych Facebook: David F Marks LinkedIn: David F Marks
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