A court case in France recently highlighted the dangers of dieting. Dr Pierre Dukan is a best-selling author whose protein-based diet is followed by Hollywood celebrities and who basically says you can eat as much as you like from a limited list and you don’t need to count calories.
In the opposite corner, and being sued by Dukan, was Dr Jean-Michel Cohen, another dietician, who says slimmers should eat a limited amount of most things and exercise regularly.
Cohen was being sued for saying that there is a whole slimming industry, including doctors, profiting from these ideas, but he also upset Dukan by saying that the Dukan diet is a potentially dangerous rehash of old ideas which can increase cholesterol and lead to heart problems and breast cancer.
The case was eventually settled out of court but a report from the French health watchdog Anses surveyed these diets and 13 others and concluded that they all had dangers and weaknesses and that people would be better off just following a balanced diet. (Mothers with daughters take note!)
More than 80% of people who tried book diets put back their weight and more a year later and the head of the nutrition service at the Pasteur Institute actually said; “slimming makes you fat”.
And last Summer an article in the Sunday Times (24/7/11)providing more scientific proof that diets don’t work.
That won’t stop the diet industry’s efforts of course or the newspapers and magazines promoting them. British women start on average 3 diet regimes a year and spend £25k on diets over their lifetime. If you think you know all about diets try this BBC quiz
One in four UK adults is overweight or obese and 16% are trying to shed weight at any one time. The problem is basically that once you gain weight it’s there to stay. Fewer than 10% of people who diet keep the weight off, the other 90% put it back on within a year. There are some advantages to dieting as you probably eat more healthily and may exercise more but yo-yo dieting is not good for you.
The Medical Research Council’s National Survey of Health & Development followed over 5,000 men and women from birth in 1946, and 20,000 people born in 1958. They measured weight and blood pressure and assessed lifestyles.
Interestingly both groups started putting on weight in the 1980s and since then people have been increasing in weight throughout their life. Men tend to put weight on steadily but for women it starts slowly and accelerates in their mid-30s (perhaps after having children?).
The Health Survey for England (2009) shows that 14% of kids and 25% of adults are obese and at least the same percentages are overweight. Excess body fat leads to a higher risk of diabetes, heart disease, arthritis, and cancer.
An endocrinologist, Professor Nick Finer, was reported suggesting that we have not evolved to tackle obesity as it has only become a problem since the mid-20th century. Previously there would have been an evolutionary advantage to be able to store fat in our bodies.
Even the idea of a set point for weight no longer seems true as it becoming overweight can rest it to a higher level. So there must be a ratchet effect if losing weight doesn’t reset it lower.
The government has been encouraging people to lose weight to combat the obesity epidemic and has encouraged GPs, pharmacists, and dietitians to offer weight loss programmes.
Researchers have now compared the NHS-provided programmes with private sector provision. Overweight patients selected by their GPs in South Birmingham were offered the chance to be referred to a weight-loss programme paid for by the NHS. Half of the patients were referred to NHS programmes and half to commercial slimming clubs: WeightWatchers, Rosemary Conley, and Slimming World.
The greatest weight loss was 4.4kgs after 12 weeks for patients who attended Weight Watchers. The NHS programmes achieved a weight loss of only 1.4kgs. despite being 50% more expensive than the private slimming clubs. After a year the figures for weight lost were:
- WeightWatchers: 3.46 kgs (4.43 kgs after 12 weeks)
- Rosemary Conley: 2.12kgs (4.23 kgs after 12 weeks)
- Slimming World: 1.89kgs (3.56 kgs after 12 weeks)
- NHS provision: 0.83kgs (1.37 kgs after 12 weeks)
One reason for the private slimming club success is that the dieters went back to them every week. This may not have been the case with the under-resourced NHS.
As the figures show people couldn’t maintain their early weight loss over a full year. Other research has shown that people achieve their maximum weight loss after six to eight months and there appears to be a natural plateau effect. It seems people find it hard to stick to a diet for longer than 6 months and the majority give up.
Clearly dieting alone is not enough. Eating more healthily is a side effect of dieting which is to be encouraged but exercise rarely gets a mention. If people were fitter they would be able to exercise more and attain a healthier body weight as well as strengthening their bodies and having more flexibility. This in turn would make them healthier – a virtuous circle.