WEIGHT MANAGEMENT POPULAR FAD DIETS Ali Hutton Today’s high prevalence of obesity, combined with Registered less than satisfactory results using traditional Dietitian, Vitaflo International weight-control methods, has helped to foster the popularity of fad diets.1 The purpose of this article is to look a little closer at three of these diets, Ali works as a Dietitian in to enable a better understanding of them, Medical Affairs so that we can offer our patients more and Marketing at Vitaflo informed advice should they wish to International and commence one. as a Freelance Dietitian at the Grosvenor As dietitians, we are often asked for for (i.e. meat and seafood) Nuffield Hospital in Chester. our opinion on or advice around and gathered (i.e. eggs, nuts, seeds, commencing a popular or fad diet, fruit, vegetables, herbs and spices).4,6 and sometimes we find that a patient This means that cereal grains, dairy has already commenced one. With an products, refined sugar, legumes, increased access to and use of the internet potatoes, processed foods, alcohol and and social media, new diets are reaching salt are excluded.2,4 our patients every day, making it hard to Advocates of the Paleo diet claim that keep up-to-date with all of them. as a long-term healthy eating plan this For full article The British Dietetic Association diet can achieve weight-loss, improve references (BDA)2,3 and NHS Choices4 have created lipid profiles5 and reduce the risk of please email useful lists of the most current popular diabetes, heart disease, cancer,4 metabolic info@ 7 networkhealth and fad diets, outlining the claims syndrome, acne vulgaris and myopia. group.co.uk behind and the pros and cons of each. The diet has some positive aspects, Many of these diets are endorsed by or such as encouraging an increase in the associated with celebrities and include consumption of fruits and vegetables the Paleolithic diet, the Bulletproof diet, and a reduction in the consumption of the Super Elixir diet, the No Sugar diet, processed foods.4 It is simple, flexible the 5:2 diet, the Dukan diet and the and doesn’t involve calorie counting. South Beach diet. Here, I will be taking The Paleo diet has, however, been a closer look at three of these diets. shown to be 9.3% more expensive than a diet of similar nutritional value,6 which THE PALEO DIET may limit the diet’s use to those on a One of the most controversial diets in higher income. The BDA2 deems the recent times is the Palaeolithic diet, diet to be unbalanced, time-consuming also known as the Stone Age diet, the and socially-isolating, and one which Caveman diet, or simply the Paleo could comprise a healthy relationship diet.5 The Paleo diet is a regime based with food. It also warns that excluding on the supposed eating habits of our dairy completely from the diet, without hunter-gatherer ancestors during the very careful substitution, could Paleolithic era, before the development compromise bone health due to a lack of agriculture around 10,000 years ago.4 of calcium. Indeed, a number of studies It is described as the diet that humans have shown that calcium intake is below are genetically adapted to, containing the recommended amounts in those only foods that can be hunted or fished following the Paleo diet.6,7,8 24 www.NHDmag.com June 2016 - Issue 115 Most studies on the Paleo diet are small, THE DUKAN DIET short, heterogeneous in design and The Dukan diet is a weight loss plan devised underpowered5 and more long- by French Doctor, Pierre Dukan. It claims to term research is needed to show achieve a weight loss of up to 2lb per week and conclusively whether or not it is as to promote long-term weight management.4 effective as some people claim. There It is a low-carbohydrate, high-protein diet are no accurate records of the diet of and consists of four phases. The attack phase our Stone Age ancestors, so the Paleo involves adhering to a strict lean protein diet for diet is largely based on an educated five days, with the aim of achieving rapid weight guess, with its health claims lacking in loss. Carbohydrate (including fruit and vegetable scientific evidence.4 Doing a quick internet search sources) is off limits, with the exception of a small will reveal a lot of conflicting advice around the amount of oat bran. The cruise, consolidation Paleo diet, with some websites supporting the and stabilisation phases of the plan involve diet9,10 and others criticising it.11,12 Taking all of the progressive reintroduction of some fruit, this into consideration, it is little wonder our vegetables and carbohydrate, and eventually patients can become misled and confused by this all foods.14 There is no limit to how much can be diet. eaten during the plan’s four phases, provided People on the Paleo diet should be referred that there is strict adherence to the rules of the to an accredited dietitian for individualised plan. There is no time limit on the final phase, advice and to discuss potential nutritional which involves having a ‘protein-only day’ once inadequacies such as calcium.5 Encouraging per week and taking regular exercise.4 an increase in activity levels that mimic our Studies have demonstrated that the diet Paleolithic ancestors, rather than trying results in a reduced energy intake, which is to copy their supposed diet, has also been responsible for the lowering of body mass.15 The NHD Magazine_0516_path.ai 1 24/5/16 10:29 AM recommended.4,13 rapid weight loss and prescriptive nature of the C M Y CM MY CY CMY K www.NHDmag.com June 2016 - Issue 115 25 WEIGHT MANAGEMENT The Paleo diet is a regime based on the supposed eating habits of our hunter-gatherer ancestors . containing only foods that can be hunted or fished and gathered . diet are likely to be key motivators for people like vegetables, fruit, dairy products and nuts, who wish to follow the Dukan diet. leading to a less than healthy diet. A number of side effects of following the Dukan Fruit juice receives bad press mainly due diet have been reported and include bad breath, to its high sugar content,21 but consumption of a dry mouth, tiredness, dizziness, insomnia and 100% orange juice has been positively associated nausea from cutting out carbohydrate, as well as with nutrient adequacy and diet quality, with no constipation from a lack of wholegrains, fruit and increased risk of overweight/obesity in children22 vegetables in the early stages.4 More worryingly, or adults.23 There is also convincing evidence from studies have warned that nephrolithiasis is a epidemiological and clinical studies that pure fruit potential side effect and so, persons with a known juices reduce the risk of CVD,21 which demonstrates history of this disease should not follow this that excluding a whole food group such as fruit from diet.14,16 Concerns have also been raised about the the diet because of its sugar content can actually potential progression of chronic kidney disease and remove elements of the diet that are beneficial to the increase in cardiovascular risk when following health. The BDA3 advocates a whole diet approach, the diet.14 One study doubted the efficacy of the rather than a focus on a single food or nutrient. Dukan diet in glucose tolerance control and weight As with the Paleo and Dukan diets, there is a loss,16 whilst another study revealed a lower intake large volume of conflicting advice on the internet of calcium, iron, potassium, vitamin C and folate, and social media around the No Sugar diet.24,25,26 but excessive amounts of protein, phosphorus, The health benefits of reducing sugar intake have sodium, vitamin A and vitamin D.15 been well documented over the years, but even the In terms of safety, there is little long-term Action on Sugar campaign27 is aiming for targets to information on the health effects of high-protein reduce the amount of sugar added to food and not diets16 such as the Dukan diet. An internet search the complete exclusion of sugar from the diet. on the Dukan diet will reveal both success stories of people who have followed it17,18 and warnings CONCLUSION against following it.19,20 Again, given the lack of Given the lack of robust evidence for or against robust evidence and the myriad of confusing popular or fad diets and the large amount of messages around the diet, it is easy to understand conflicting advice on the internet and social why patients are unsure of whether or not it is an media, it is easy to understand how patients appropriate weight-loss option for them. may become misled and confused. As dietitians, rather than dismiss outright a patient’s desire to THE NO SUGAR DIET commence one of these diets, it may be better to The No Sugar diet involves exclusion of all types discuss the lack of clinical evidence to support the of sugar from the diet. The BDA3 acknowledges diet and highlight the potential adverse effects that cutting down on free sugars, adding less on health that following the diet may have. If sugar to food and consuming fewer products they still wish to follow the diet, then suggesting already containing added sugar, in addition to an adapted version of the diet (i.e. that doesn’t being label aware, are positive elements of this ban any food groups), or offering advice on how diet.