Low-fat diet fails for maintenance after weight loss

US researchers evaluated the effects of three maintenance diets following weight loss of 10–15% in 21 young overweight and obese adults. In a cross-over study, participants consumed a low-fat, low-GI and very low-carbohydrate diet for four weeks each.

Decreases in energy expenditure were greatest with the low-fat diet, intermediate with low-GI and least with the low-carb diet.

The low-carb diet improved metabolic function the most but increased cortisol excretion and C-reactive protein and the low-fat diet increased serum leptin.

“A strategy to reduce glycaemic load rather than dietary fat may be advantageous for weight-loss maintenance and cardiovascular disease prevention,” the authors concluded, adding that the study challenged the notion that a calorie was a calorie.

Professor Jennie Brand-Miller, from the Boden Institute, Sydney, and director of the board of Glycaemic Index Foundations