For too long we have been told that exercise helps weight loss and cuts obesity, but an Indian-origin doctor and his colleagues say that being dangerously overweight is down to bad diet rather than a lack of exercise.
In an article for the British Journal of Sports Medicine, cardiologist Aseem Malhotra and co-authors T Noakes and S Phinney wrote: “Let us bust the myth of physical activity and obesity. You cannot outrun a bad diet”.
Challenging conventional wisdom that made headlines Thursday, the article said those who want to avoid excess weight gain should adopt a diet that is high in fat but low on both sugar and carbohydrates.
“The public health messaging around diet and exercise, and their relationship to the epidemics of type 2 diabetes and obesity has been corrupted by vested interests. Celebrity endorsements of sugary drinks, and the association of junk food and sport, must end”.
“The ‘health halo’ legitimisation of nutritionally deficient products is misleading and unscientific. This manipulative marketing sabotages effective government interventions such as the introduction of sugary drink taxes or banning of junk food ads. Such marketing increases commercial profit at the cost of population health”.
The study said that while physical activity is useful in reducing the risk of developing heart disease, dementia and other conditions, it “does not promote weight loss”.
The authors add: “Members of the public are drowned by an unhelpful message about maintaining a ‘healthy weight’ through calorie counting, and many still wrongly believe that obesity is entirely due to lack of exercise.”
That “false perception”, they claim, “is rooted in the food industry’s public relations machinery, which uses tactics chillingly similar to those of big tobacco … denial, doubt, confusing the public and even buying the loyalty of bent scientists, at the cost of millions of lives.”
However, experts dismissed their conclusions. Catherine Collins of the British Dietetic Association said the doctors had down-played the metabolic and physical health benefits of undertaking even moderately intense exercise and had used “incomplete evidence” to make their case.
Susan Jebb, professor of diet and population health at Oxford University, said: “The authors fail to note that weight loss programmes that combine diet and physical activity are the most successful route to weight loss in both short (three to six months) and medium term (12 months)”.