Research proves
diets don’t
achieve lasting
weight loss

Professor Traci Mann, a psychologist at the University of California in Los Angeles, says: “Diets do not lead to sustained weight loss or health benefits for the majority of people. You can initially lose five to 10 per cent of your weight on any number of diets, but then the weight comes back.

 “We found that the majority of people regained all the weight, plus more. Sustained weight loss was found only in a small minority of participants, while complete weight regain was found in the majority.”

Prof Mann analysed 31 long-term studies of diet regimes and concluded that most people would have been better off not dieting at all.

“Their weight would be pretty much the same, and their bodies would not suffer the wear and tear from losing weight and gaining it all back again.”

Judy More, spokeswoman for the British Dietetic Association, said the results were not surprising. “When people are on a diet, they feel as if they are denying themselves things, so when they come off it, they think, ‘Oh, thank God, I can go back to eating’.”

She added that people who wanted to lose weight should look at the challenge as a change in lifestyle. “They’ve got to find a physical activity they enjoy, whether it's walking or going to the gym or taking up a new sport.”

We have to look for new answers, says professor

As people put on pounds the body accepts the new weight and tries to restore any losses as quickly as possible. Nick Finer, professor of obesity medicine at University College London, says the average long-term weight loss achieved through dieting by most obese adults is so small as to be almost irrelevant.

Humans evolved in unpredictable environments where food was scarce and our bodies are programmed to maintain our body weight at all costs.

“When people become fat their hormone and nervous systems adapt to the new weight – so it’s very hard for anyone to fight that by cutting their food intake, especially in a world where food is so plentiful. It means we have to look for new answers.”