Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet: a randomized trial.

Description

The purpose of this study was to compare the long-term (2 years) effects of treatment with either a low-carbohydrate or low-fat, calorie-restricted diet on body weight, cardiovascular risk factors and bone mineral density. The study population included 307 participants with a mean age of 45.5 years and mean body mass index of 36.1 kg/m2. Results showed that participants had similar and clinically significant weight losses with either a low-carbohydrate or low-fat diet at 1 year (11% weight loss) and 2 years (7% weight loss) when combined with a comprehensive lifestyle modification program. However, differential effects on plasma lipid concentrations were found according to dietary macronutrient composition. For instance, the low-carbohydrate diet produced a much greater increase in plasma HDL cholesterol concentrations than did the low-fat diet during the 2-year study. Changes in bone mineral density associated with weight loss did not differ between diet groups. Moreover, decreases in body fat mass and fat-free mass were similar in both diet groups. Thus, these results suggest that either diet can be used to achieve successful long-term weight loss if coupled with behavioural treatment.