low-fat diet leads to more fat loss than carb restriction

Contrary to popular claims, restricting dietary fat can lead to greater body fat loss than carbohydrate restriction, even though a low-carb diet reduces insulin and increases fat burning, new researcher has found.

"A lot of people have very strong opinions about what matters for weight loss, and the physiological data upon which those beliefs are based are sometimes lacking," said one of the researchers Kevin Hall from National Institute of Diabetes and Digestive and Kidney Diseases, part of US National Institutes of Health (NIH).

"I wanted to rigorously test the theory that carbohydrate restriction is particularly effective for losing body fat since this idea has been influencing many people's decisions about their diets," Hall noted.

For the study, the researchers confined 19 consenting adults with obesity to a metabolic ward for two dieting periods of two weeks each.

At the end of the two dieting periods, the researchers found that body fat lost with dietary fat restriction was greater compared with carbohydrate restriction, even though more fat was burned with the low-carb diet. 

The study was published in the journal Cell Metabolism.