Fad diets 'make you gain weight'

“Fad diets make you fat,” according to the Daily Express, which said that many quick fixes for obesity are “doomed to end in failure”.

The claim was based on a conference presentation being given by Professor Chris Hawkey, president of the British Society of Gastroenterology. The newspaper quotes a press release on his talk, which says that people should avoid extreme food regimes based on “theory rather than evidence”. These include only eating grapefruit and  the Victorian practice of chewing each mouthful of food 32 times.

While people may turn to extreme diets to lose weight, the most well-established way to maintain both good health and an ideal body weight is to adopt a balanced diet, take regular exercise, not smoke and limit alcohol consumption.  

What is the basis for these current reports?

Professor Chris Hawkey is speaking today at GASTRO 2009, an annual international conference on gastroenterology, the field of medicine concerned with the stomach, intestines and other organs related to digestion. Professor Hawkey is the president of the British Society of Gastroenterology (BSG) and a professor of gastroenterology at the University of Nottingham.

Professor Hawkey’s presentation focuses on the fact that, despite the rise in popularity of diets and extreme food regimes, the obesity problem appears to be getting worse. He also states that balanced eating is more important than some of the “quirky” practices being adopted in the name of keeping slim and healthy.

To illustrate his point, Professor Hawkey focusses on “food fads of yesterday and today”, discussing how habits in eating and dieting have changed through time and particularly how some diets quickly rise in popularity but then fade into obscurity. He also presents the findings from a recent survey commissioned by the BSG which examined public attitudes towards food and diet.

What examples does he draw on?

The press release detailing Professor Hawkey’s presentation mentions several food fads. In the available summary of his talk, it is not clear whether he will discuss the scientific evidence to support or disprove them, or whether they are solely included for context. More detail will be available when the conference is over and any transcripts and related research papers are made available.

The food fads discussed by Professor Hawkey include:

• Fruitarian diets based on the belief that fruit was man’s original diet in the Garden of Eden.
• The Hollywood Grapefruit Diet, which is based on the claim that grapefruit contains an enzyme that can burn body fat.
• Consuming apple or cider vinegar before a meal to counteract alkaline substances in the diet.
• The Atkins Diet, which is based on the idea that diets that are low in carbohydrates may have a nutritional advantage because they encourage the body to burn more calories. As an interesting aside, Professor Hawkey notes that, at its peak, about 9% of all Americans followed the Atkins diet until the death of its founder, which was thought be linked to his diet.
• The Max Gerson Diet, which included rectally administered hydrogen peroxide and daily consumption of an extract of raw calf liver. He claimed his diet could cure cancer and other chronic illnesses.

Professor Hawkey is quoted as saying that “the main problem facing society is not the content of our diet but its quantity and consequent obesity.” He discusses his idea of a “Feed the World” approach to weight reduction, where consumers would purchase a 15% reduced portion of food for the same price as a full-size portion and the cost difference would go to famine relief. He speculates that “frustrated idealism” may lie beneath eating disorders. An exposé of the myths behind some of these fads will be welcome in this context.

What did the the survey on diet find?

Research commissioned by the British Society of Gastroenterology found that:

• One in 20 (5%) women would try the Atkins diet to lose weight.
• Only 2% of British people think the Atkins diet is good for their health.
• One in five (21%) Londoners would try weight-loss pills to lose weight.
• Only 65% of women would increase their exercise levels if trying to lose weight.
• Nearly one in 10 (9%) British people think a diet with a high fish content is bad for their health.

The figures come from an online survey of 1,959 adults conducted by YouGov research company in September 2009.

What is the bottom line?

There are numerous well-documented benefits associated with a healthy, balanced diet. These include preventing long-term illnesses, increasing lifespan and improving cardiovascular health. Consuming a healthy diet, doing regular exercise, not smoking and limiting alcohol are the most well-established ways of maintaining both good health and a healthy body weight.