Macro partitioning
Low-carbohydrate diets (≤45% energy from carbs) are at least as effective as low-fat diets (≤30% energy from fat) for reducing body weight and waist circumference over interventions of 6 months or longer.
If you are overweight or obese, switching to a low-carbohydrate diet (limiting carbs to 45% of calories or less) will likely result in similar weight loss to a low-fat diet over the long term (6+ months). You do not need to restrict calories more strictly than a low-fat dieter; simply shifting macronutrient ratios is sufficient to achieve comparable weight reduction.
These findings suggest that low-carbohydrate diets are at least as effective as low-fat diets at reducing weight and improving metabolic risk factors.
Why this rating
Meta-analysis of 23 RCTs with 2,788 participants provides high statistical power, though heterogeneity exists for weight.
Source
Effects of Low-Carbohydrate Diets Versus Low-Fat Diets on Metabolic Risk Factors: A Meta-Analysis of Randomized Controlled Clinical Trials
Tian Hu et al. · American Journal of Epidemiology · 2012
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