The ketogenic diet and lymphedema A point and counterpoint discussion

The ketogenic diet has grown in popularity these last few years for both the general public and those living with lymphedema. The diet has also garnered significant controversy, specifically within the lymphedema community. We took the opportunity to have some of the common questions addressed with leading opinion experts.

The following POINT and COUNTERPOINT articles are the compilation of several communications including Zoom interviews between Dr. Anna Towers (Editorial Board member and Director of the Lymphedema Program at the McGill University Health Centre) and our esteemed authors. Our aim was for readers to be educated and presented with a balanced view in order to draw their own conclusions. It is imperative that you consult your healthcare provider before making any drastic dietary change. We recommend you also review the references and additional resources the authors have provided, that can be found online at https://canadalymph.ca/pathways-references.

POINT

Key points addressed by Leslyn Keith, in collaboration with Eric Westman.

What is the history of the ketogenic diet?

In our clinical practices, a ketogenic diet has been a valuable intervention for lymphedema and lipedema symptom management. Promoting health through ketogenic nutrition is not new, as it was commonly referenced in medical papers in the first half of the last century for treatment of diabetes and epilepsy before medications existed for these conditions1,15 Studied extensively in the last 25 years, a ketogenic dietary plan has shown considerable promise as a viable intervention for a variety of health conditions, such as obesity, diabetes, heart disease, epilepsy, cancer, and mental health disorders4,7,9,18,23,37. In this article, we answer a few common questions and discuss how ketogenic nutrition can be an important part of lymphedema and lipedema treatment and self-management.

Can you please explain the ketogenic diet?

A ketogenic diet is a pattern of eating that restricts carbohydrates, such as starches and sugars, to such a degree (usually <50 grams of carbohydrate per day) that ketones are generated20,35. Therefore, a ketogenic diet really is a low-carbohydrate diet that harnesses the beneficial effects of ketones by virtue of being an ultra-low-carbohydrate diet.

The Carbohydrate-Insulin Model (CIM) has been proposed as a mechanism for how a very low carbohydrate ketogenic diet can promote not only healthy weight loss but also improved overall health21 This model suggests that carbohydrate restriction limits the body’s access to glucose and necessitates that an alternate fuel source be used, namely ketones and fatty acids. The decreased consumption of carbohydrates has the added benefit of reducing the amount of circulating insulin. Insulin is released from the pancreas in response to glucose, the basic component that all carbohydrates break down into. One of the many jobs of insulin is to limit fat-burning and increase fat storage. Thus, limiting carbohydrate consumption will allow body fat to be used for energy instead of being stored and contributing to obesity.

What is the proven safety and effectiveness of a ketogenic diet. For example, aren’t carbohydrates essential?

The human body actually needs very little carbohydrate, or glucose, and can function very well using ketones and fatty acids for fuel34 Because humans can make any needed glucose through a biological process called gluconeogenesis, restricting carbohydrate consumption to very low levels is perfectly safe33. New research has shown the lymphatic system also does well with limited carbohydrate consumption. Lymphatic endothelial cells, those cells that form the vessel walls of the lymphatic system, have a preference for ketones, even in the presence of glucose11, and ketones and fatty acids elicit lymph vessel growth36.

Do people need to be concerned regarding cholesterol with ketogenic eating?

For the most part, it seems that following a ketogenic eating plan has a positive effect on cholesterol. For instance, in the majority of studies comparing low-carbohydrate or ketogenic diets with low-fat diets, the lipid panel becomes more favourable with carbohydrate restriction22 In a pilot study of nine women with lipedema, triglycerides reduced significantly after seven weeks on a ketogenic diet but then returned to the higher baseline levels after just six weeks back on a standard high carbohydrate diet27 It has been shown, however, that cholesterol levels in the blood may rise during weight loss28 This occurs with any diet, not just a ketogenic diet. It should also be noted that there is a small subset of the population that will experience elevation of certain lipoproteins with a ketogenic diet. There is currently a study underway to understand if the high levels of LDL in this group are harmful24

Are there any clinical trials showing that the ketogenic diet is safe?

Nutrition research, especially studies of long duration, can be challenging and costly8. For this reason, diet studies that last longer than two years tend to be observational, which means we are unable to draw any conclusions regarding causal relationships. However, it gives us a place to start. One such very large observational study, the Prospective Urban Rural Epidemiology (PURE) lifestyle study, followed over 135,000 patients from 18 different countries in five continents for approximately 7½ years31 The researchers reported that their data on diet showed a benefit with higher fat consumption, even saturated fats. They suggest that a diet too low in saturated fats may be harmful. An example of a clinical trial (i.e., not simply an observational study) is the two year study by Virta Health that examined the effectiveness of a ketogenic diet for diabetes management4. This study showed excellent outcomes (including better blood sugar control, weight loss, reduced need for medications, and diabetes remission) sustained over the two years without adverse events. Dr. David Ludwig20, in his paper reviewing the evidence for a ketogenic diet, reported meta-analysis reviews of a total of 77 dietary clinical trials that showed higher fat diets, including a ketogenic diet, were found to be superior to all low-fat diets for health outcomes.

Can you explain the pathophysiology of lymphedema & lipedema?

While lymphedema starts with excessive fluid accumulation and lipedema begins with fat tissue expansion, both conditions can ultimately result in similar chronic tissue and skin changes such as edema, fat proliferation, inflammation and fibrosis10. Additionally, both conditions can be exacerbated by a third chronic condition: obesity. While the current prevalence of obesity has topped 42% in US adults29, the occurrence of this condition is even more pervasive in lymphedema and lipedema populations17, 5. Unfortunately, lymphatic function may be irreversibly damaged with a BMI of above 50 kg/m2 14 For this reason, it becomes critical to address both the lymphatic disorder and obesity with a single dietary plan. The fact that the presence of obesity, but not a high-fat diet, was shown to negatively impact lymphatic function in two independent animal studies12,13, gives us hope that a ketogenic diet may be the answer.

Why do you recommend the ketogenic diet for lymphedema and lipedema?

Recent research has confirmed what we have seen in clinical practice: characteristics and underlying pathophysiology of lymphedema and lipedema may be favourably impacted by a ketogenic diet. For instance, edema and limb volume reduction in participants with lymphedema has been seen in response to a ketogenic diet in both animal and human studies11,28,36, with a current clinical trial in progress that has already shown promising results32 Pain reduction, often independent from weight loss, was observed in several studies using a ketogenic diet for participants with lipedema2,6,27. Better outcomes were observed for women with lipedema, including improved blood panel, decreased pain, and reduced body fat on the lower body, with a ketogenic diet compared to a moderatecarbohydrate or a low-fat diet3,16

Do you have any concluding statements?

In our clinical experience, even when weight loss is not desired or warranted, ketogenic nutrition may prove to be central to managing chronic lymphatic and fat disorders such as lymphedema and lipedema. Because a ketogenic diet is a weight-regulating diet rather than an exclusively weight-loss diet, this eating plan can be used to promote health, not just to promote weight loss26. For those who find it a challenge to adhere to very low carbohydrate levels long term, it has been shown that a modest decrease in carbohydrate has beneficial effects on lipedema symptoms, though not to the prescription-strength effectiveness of a ketogenic diet16 The most effective eating plan is the one that is satisfying and sustainable over a lifetime. LP

Leslyn Keith is a certified lymphedema therapist with a Clinical Doctorate in Occupational Therapy. She has been treating lymphedema and lipedema for over 20 years. Dr. Keith is the author of two books that promote a ketogenic diet for lymphatic disorders and developed Lymphatic Lifestyle Solutions.

Eric Westman, MD, MHS specializes in obesity medicine and internal medicine and has conducted several clinical trials and authored several books on low carbohydrate and ketogenic diets. He was on the doctoral committee for Leslyn Keith’s pilot study examining the effectiveness of a ketogenic diet for lymphedema and obesity.

COUNTERPOINT

Key points addressed by Cate Ward, in collaboration with Christopher Gardiner.

Theketogenic diet, commonly known as the “keto diet,” is a high-fat, low-carbohydrate diet that has gained popularity in recent years, however, has been used as a treatment for epilepsy since the 1920s. Proponents of the diet claim that it can lead to weight loss and other health benefits. However, there are also potential drawbacks to the diet, including: risk of nutrient deficiencies, increased saturated fat intake (unadvised for fatty liver disease and cardiovascular health), difficulty eating in social situations, reduced ability to maintain over a long period of time, and decreased athletic performance. In this article, we will discuss the pros and cons of the ketogenic diet for people with lymphedema.

Weight loss can be especially beneficial for people with lymphedema, as excess weight can put additional pressure on the lymphatic system and worsen the condition. Losing weight can help to reduce the risk of developing lymphedema or improve symptoms in those who already have the condition. It is important to work with a healthcare professional to determine the most appropriate diet for individual needs.

How does the keto diet compare with other diets?

One potential benefit of the ketogenic diet for people with lymphedema is weight loss. The diet is designed to promote the production of ketones, which are produced when the body breaks down fat for energy. A keto diet is quite restrictive, and thus, may encourage weight loss by moving diet participants into a calorie deficit. However, it is important to note that any diet that moves an individual’s intake into a calorie deficit can lead to weight loss. In the Keto-Med trial by Dr. Christopher Gardner and his group at Stanford, participants lost similar amounts of weight on either a well formulated ketogenic diet or a Mediterranean plus diet, with no significant differences across the groups (Gardner et al., 2022).

What were the results of the Keto-Med study?

Keto-Med study compared two low-carb diets, the well-formulated ketogenic diet (WFKD) and the Mediterranean-plus diet (Med-Plus), in adults with prediabetes or Type 2 Diabetes Mellitus (T2DM). The main differences between the two diets were the inclusion or exclusion of legumes, fruits, and whole grains. The study found that both diets resulted in significant improvements in glycated hemoglobin (HbA1c) levels after 12 weeks, but there were no significant differences between the two diets for this outcome. The dietary adherence assessment indicated similar levels of adherence between the two diets. Although weight loss was not discouraged, the study diet design did not include a prescribed energy restriction and was not intended to be a weight loss study. Participants were told to eat until they were satiated throughout the study. Significant weight loss occurred for both groups (WFKD and Med-Plus) at week 12 of the study, however, no differences in weight loss were seen across groups.

What about long-term sustainability?

It may be difficult to maintain adherence to a ketogenic diet in the long-term, as it requires a significant change in eating habits and may be challenging to stick to. In the Keto-Med trial, adherence to both Med-Plus and WFKD were very similar in the intervention (Landry, M., et al. 2021). However, it is important to note that each diet period was only 12 weeks long. In this paper, Dr. Landry highlights how many studies fail to capture adherence, which is a shortcoming. Longer-term studies are needed to assess sustainability of ketogenic diet adherence over time.

Can you explain possible nutrient deficiencies in the keto diet?

Although following a ketogenic diet may aid in weight loss, there are also potential drawbacks to the ketogenic diet for people with lymphedema. One concern is the risk of nutrient deficiencies. The diet is low in carbohydrates, which can lead to a deficiency in important nutrients such as fiber, vitamins, and minerals. It can also be low in fruits and vegetables, which are important sources of micro-nutrients and fiber, potentially disrupting gastrointestinal regularity and is not ideal for long term health outcomes.

What about fitting the diet into daily life?

Following a ketogenic diet can also be challenging in social situations, as it may be difficult to find food options that fit within the strict guidelines of the diet. It may be necessary to bring separate food to events, and to make special requests when dining out. When dining with family members who do not follow a ketogenic diet, it can be challenging to prepare separate meals that fit the keto diet requirements. Aside from medical treatment, a ketogenic diet is generally not recommended for children due to its restrictive nature, as their growing bodies and developing brains have different nutritional needs compared to adults. Children require a balanced diet that includes a variety of nutrients, including carbohydrates, to support their growth and development.

Is fatty liver disease a concern?

The quality of a ketogenic diet can impact metabolic health, including cardiovascular health and liver function. The high-fat nature of the keto diet may lend to higher intake of saturated fat. Without emphasis on a “wellformulated ketogenic diet” (low saturated fat diet), as in the Keto-Med trial, a keto diet high in saturated fat may lead to increased risk of both cardiovascular disease and fatty liver disease. Increased saturated fat intake can lead to increased LDL cholesterol, which is a risk factor for developing cardiovascular disease. Additionally, patients with fatty liver disease are generally advised to consume a diet low in saturated fat, thus, a keto diet is likely not a great choice in managing fatty liver disease.

Is there a risk for decreased muscle mass?

Exercise is an important lifestyle intervention to aid in weight loss, weight maintenance, and longevity. Some studies3 suggest following a keto diet does not provide enough carbohydrates to support intense exercise or athletic performance, thus in this respect, can lead to decreased muscle mass. A ketogenic diet can provide adequate protein to help maintain muscle mass, however, exercise and strength training are important to both gain and preserve muscle mass.

In conclusion, weight loss through any diet that reduces calorie intake may provide similar benefits for people with lymphedema, without the drawbacks of ketogenic diet that include the risk of nutrient and fiber deficiencies, potentially increased saturated fat intake, difficulty eating in social situations, questionable long-term adherence, and decreased athletic performance. It is important for people with lymphedema to work with a healthcare professional to develop a treatment plan that is safe and effective for their individual needs. LP

References/resources can be found at https://canadalymph.ca/pathwaysreferences.

Cate Ward, PhD, RD is a postdoctoral fellow at Stanford School of Medicine. Her current research focuses on the metabolic effects of a plant-based diet. Dr. Ward works with patients via her private nutrition practice. https://www.catepward.com

Christopher Gardiner PhD is a nutrition scientist with more than 26 years of research, studying the best foods to consume for optimal health and how to motivate people to achieve healthy dietary behaviours. He recently led the Keto-Med study, comparing outcomes of the well-formulated ketogenic diet or a Mediterranean-plus diet.

References can be found at https:// canadalymph.ca/pathways-references