Lo-carb ‘slightly better’ than low fat diets for weight loss

Adopting a low-fat diet and foregoing guilty pleasures such as crisps and fry-ups may not be the best way to slim, a study has found. Experts who analysed data on more than 68,000 adults concluded that curbing fat intake did not lead to greater weight loss than low-carbohydrate or Mediterranean diets. Scientists pulled together information from 53 trials comparing the ability of low-fat and other kinds of diet to shed unwanted pounds over a period of at least one year. They found no significant difference in average levels of weight loss between reduced-fat and higher-fat diets.

Behind current dietary advice to cut out the fat, which contains more than twice the calories per gram of carbohydrates and protein, the thinking is that simply reducing fat intake will naturally lead to weight loss. But our robust evidence clearly suggests otherwise.

Lead scientist Dr Deirdre Tobias from Brigham and Women’s Hospital and Harvard Medical School

Diets that cut out fat were actually slightly less effective than those based on lowering carbohydrate consumption, the researchers reported in The Lancet Diabetes & Endocrinology medical journal. Compared with not dieting at all, avoiding fat resulted in 5.4 kilograms (12 pounds) being shed after a year, while low carbohydrate diets added another 1.15 kilograms (2.5 pounds) of weight loss.

Weight losses of 5 kg may be less than many people might hope for but we know from many other research studies that this brings surprisingly large health benefits, more than halving the risk of developing diabetes in people with raised blood sugar.

British nutritionist Professor Susan Jebb, from Oxford University

Health low-fat diet