FOOD & DRINK
WHOLEGRAINS IN THE UK Emma Berry Registered Associate Nutritionist Emma is a recent Nutrition graduate with an interest in public health nutrition.
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The most recent Scientific Advisory Committee of Nutrition (SACN) report on Carbohydrates and Health1 was heavily discussed in the media due to its change in the guidance related to the consumption of free sugars.2 Free sugars were advised to be less than 5% of the total daily intake, which was met with much controversy. However, there was also found to be a change in the guidelines related to fibre intakes. Fibre intake was advised to increase to 30g/day (as defined by AOAC fibre) for an adult aged over 18, through eating more wholegrains and cereal fibres. This increase is fairly substantial compared to the previous guidance to consume 23-24g/day.1 30g of fibre a day would be the equivalent of five portions of fruits and vegetables, two slices of wholemeal bread, a portion of high fibre breakfast cereal, a baked potato and a portion of whole wheat pasta.1 Following the report, the British Nutrition Society developed a sample menu to demonstrate how the increase in daily fibre intake could be achieved.3 The sample menu demonstrates a sevenday food plan, which consists of three meals and two snacks per day. It also details the nutritional values of each day. Despite the SACN guidance encouraging us to increase the consumption of wholegrains, there is no established definition for what a wholegrain food consists of, or any recommendations on the amount of wholegrain foods to consume. The SACN report1 advised foods which are considered wholegrains to be whole wheat, whole wheat flour, wheat flakes, whole and rolled oats, brown rice, oat flakes, bulgur wheat, whole rye and flour, whole barley and oatmeal. Work has been carried out to find a way to define what a wholegrain food is since this report. The Healthgrain Forum has been promoting research into defining
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wholegrain foods and encouraging consumption of wholegrains within the diet.4 The Healthgrain Forum definition of wholegrain consists of the endosperm, germ and bran being present in the same proportions as they would be in the kernel.5 These kernels can be intact, ground, cracked or flaked and the inedible parts can be removed. Figure 1 demonstrates the components of a wholegrain. The skin of the kernel is the bran, which has multiple layers and contains various nutrients. Inside the kernel is the endosperm and the germ. The endosperm is the largest part of the kernel, and contains carbohydrates, proteins and some vitamins. The germ has the potential to produce a new plant and is a source of vitamins, minerals, some protein and healthy fats. In white bread and white rice, the germ and bran are normally filtered out and the endosperm is the only remaining part of the kernel.6 The recent paper from the Healthgrain Forum put forward recommendations for a new definition to encourage universally consistent food labelling so that consumers are able to easily identify how much wholegrains are found within the food.5 The suggested labels were: 1 100% Whole Grain; 2 Whole Grain Foods (≼50% of grain is whole); 3 Foods contributing to Whole Grains (≼8g whole grains/serving).5
Figure 1: Components of a wholegrain. Diagram adapted from The Whole Grains Council.6
The skin of the kernel is the bran, which has multiple layers and contains various nutrients. The endosperm is the largest part of the kernel, and contains carbohydrates, proteins and some vitamins. The germ has the potential to produce a new plant and is a source of vitamins, minerals, some protein and healthy fats. This could make it clearer for consumers as to how much wholegrains are found within food and make it easier for them to identify wholegrain foods. This is important if we are to try and increase consumption of wholegrains within the general public. Although the UK currently has no specific recommendations for the daily amount of wholegrains to consume, some other countries do offer a guideline amount. Mann et al7 compared several countries' wholegrain consumption to the guidelines provided by the USA. These guidelines suggest an intake of 48-80g per day of wholegrains, with the study finding that in the UK National Diet and Nutrition Survey 20082011 data, only 17% met the minimum intake of 48g per day. The main intakes of wholegrains consumed came in the form of breads, breakfast cereals and a small amount from pasta. Although this data may be slightly outdated, it is likely that we may still not be consuming enough wholegrain foods. HEALTH BENEFITS
The SACN report outlined wholegrain consumption to be beneficial to cardiovascular health, as well as being linked to a reduced incidence of Type 2 diabetes and colon cancer.1 However, as the report admits a variation in the definition of wholegrain foods, the inference
of the studies discussed is quite limited. Since the SACN report, there have been further studies discussing the benefit of wholegrains. A recent systematic review found a positive association for wholegrain consumption and coronary heart disease, cardiovascular disease and cancer, as well as all-cause mortality. The mechanisms suggested for this include a general increase in fibre, with a higher level of wholegrains consumed; a reduced level of obesity with higher wholegrain consumption and a reduction in inflammation.8 However, there has been the suggestion that increased wholegrain consumption is found to correlate with higher consumption of other foods such as milk, yoghurt, fruits and vegetables.9 In a study of the National Diet and Nutrition Survey, individuals who consumed wholegrains were found to have a higher range of various nutrients compared to individuals who did not consume wholegrains. Nutrients included iron, calcium, potassium, phosphorus, thiamine and magnesium.10 From the same sample, it was found that over 70% of the participants did not consume the minimum recommended amount of wholegrains from the US. Therefore, it is important to establish if the suspected impact of wholegrains on health is wholegrain specific, or that individuals who have a higher consumption of wholegrains may have a higher intake of fibre www.NHDmag.com May 2018 - Issue 134
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FOOD & DRINK
. . . wholegrains are an important addition to an individual’s diet. They are linked to numerous health benefits and are also linked to an increase in fibre consumption, which in itself has a benefit to health. and a healthier diet in general. It’s also important to note that if the majority of the population are struggling to consume enough wholegrains, then this may need to become an important project for future public health campaigns within the UK. There have been numerous studies which have investigated how to improve wholegrain consumption, whilst also investigating the barriers to improving consumption. Kamar et al11 discussed the factors which impact adolescent consumption. The most well-known reasons for consuming wholegrains were their positive impact on the digestive system and that they were a source of longer lasting energy. However, the participants were often confused by the various food labels - using brown bread as an example of wholegrain food, supporting the importance of the clear labelling as suggested by the Healthgrain Forum. Many participants advised that wholegrain food was not part of their normal diet and was not readily available to them. While some simply disliked the taste, texture or appearance of wholegrain foods, but this depended on the individual. Although there hasn’t been much research into the barriers and facilitators of adult consumption of wholegrains in the UK, there has been work carried out in other countries. In a study by Chea et al,12 some of the barriers found included a lack of understanding about what a wholegrain food was, as well as the taste of wholegrains and the cost. This further supports the need for clear labelling, as suggested by the Healthgrain Forum. One way to encourage a higher level of wholegrain consumption is through industry reformulation. However, this is a significant challenge facing manufacturers to achieve a 28
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level of wholegrains which would be considered to be contributing to an improvement in health, while still being found palatable to the general public who don’t tend to eat much wholegrains. The foods developed need to be convenient and innovative approaches are required to take on this complex challenge.13 There should be future research into what barriers face the wholegrain consumption within adults in the UK. Research into identifying and reducing these barriers could increase the consumption of wholegrains and likely also improve the consumption of fibre. CONCLUSION
In conclusion, wholegrains are an important addition to an individual’s diet. They are linked to numerous health benefits and are also linked to an increase in fibre consumption, which in itself has a benefit to health. In other countries, there is a recommended guideline for how much wholegrain should be consumed daily, which the majority of the UK population does not meet. There are various barriers for individuals consuming more wholegrains. One major issue is a lack of consistency for how wholegrains are defined and how products containing wholegrains are labelled. Clarifying and standardising both of these, would help improve the public understanding of wholegrains. Reformulation could also be used to incorporate more wholegrains into processed foods, to increase the public consumption without individuals having to drastically change their diets. However, the first step is to establish a UK guideline for wholegrain consumption which the public can understand and use.