FRANCE'S most popular weight-loss regimes, including the number one Dukan diet, are ineffective and potentially dangerous to people's health, doctors have warned.
The Agence Nationale de Sécurité Sanitaire has issued a warning over 14 of the most fashionable diet regimes in France.
Researchers at the Institut Pasteur in Lille assessed each regime, including Atkins and Montignac, for its nutritional value and potential side-effects.
Head of nutritional research Jean-Michel Lecerf, who led the study, said the diets disrupted the body's natural metabolism and led to serious nutritional imbalances.
Out of the regimes examined, only the Weight Watchers diet was considered by the researchers to be balanced and suitable.
In the others, the protein content was typically much higher than the recommended daily intake, especially the Dukan diet, which is France's top-seller.
Some of the diets contained 10 times less fibre than the recommended level and up to twice as much salt. They also lacked vital vitamins and minerals.
The study also pointed to an increased risk of fractures and other bone problems, muscle wastage and cardiovascular problems in some of the regimes.
The research, due to be published in full later today, appears in today's Le Parisien.
Dr Lecerf told the paper that, in 95 per cent of cases, people who follow a dietary regime regain weight as soon as they finish. In some instances, the weight they regain is greater than the amount lost.
He said: "Each regime is less effective than the one before, and the weight gain afterwards is greater each time."
According to the study, about 70 per cent of people in France have followed some sort of weight-loss programme, many without consulting a doctor beforehand.
The Régime Dukan is the most popular diet in France at the moment.
Like Atkins, it is high in protein in the initial "attack" phase, but low in fat. Next comes the "cruise" phase, with protein-only days and protein-and-veg days. Potatoes are banned, as are high-calorie vegetables such as peas, carrots and sweetcorn.
More than two million copies of the Dukan book Je ne sais pas maigrir have been sold in France.
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