A study published in The Lancet Diabetes & Endocrinology has looked at the effectiveness of low-fat diets for long-term weight loss.
The researchers from Brigham and Women’s Hospital and Harvard Medical School reviewed data from 53 studies involving over 68,000 subjects which compared the long-term (over a year) effect of low-fat and higher fat dietary interventions on weight loss.
In weight loss trials, the researchers found that low carb interventions led to significantly greater weight loss than low-fat diets (2.5lbs lighter after follow-up of at least one year). Low fat interventions showed no different effect than higher-fat interventions and led to a greater weight loss only when compared with a usual diet.
However, when groups differed by more than 5% of calories obtained by fat, higher fat weight loss interventions led to significantly greater weight loss than low-fat interventions at follow-up.
Lead researcher Dr Deirdre Tobias commented on the findings: “Despite the pervasive dogma that one needs to cut fat from their diet in order to lose weight, the existing scientific evidence does not support low-fat diets over other dietary interventions for long-term weight loss. The thinking is that simply reducing fat intake will naturally lead to weight loss. But our robust evidence clearly suggests otherwise.”
She added: “The science does not support low-fat diets as the optimal long-term weight loss strategy. To effectively address the obesity epidemic, we will need more research to identify better approaches for long-term weight loss and weight maintenance, including the need to look beyond differences in macronutrient composition.”