Research

Energy balance

Low-carbohydrate, non-energy-restricted diets produce greater short-term weight loss (6 months) than energy-restricted low-fat diets, but this advantage disappears after 12 months.

If you are overweight, a low-carb diet where you don't count calories or restrict fat will help you lose more weight in the first 6 months than a standard low-fat, calorie-restricted diet. However, do not expect this advantage to last beyond a year; by 12 months, both groups lose roughly the same amount of weight. Focus on adherence, as the low-carb group had better completion rates initially.

ModerateQualifiesMEDIUM confidence
After 6 months, individuals assigned to low-carbohydrate diets had lost more weight than individuals randomized to low-fat diets (weighted mean difference, –3.3 kg... This difference was no longer obvious after 12 months (weighted mean difference, –1.0 kg...)
Alain Nordmann et al. · Archives of Internal Medicine · 2006

Why this rating

Meta-analysis of RCTs, but small sample size (447 individuals) and moderate quality (no blinding, high dropout).

Source

Effects of Low-Carbohydrate vs Low-Fat Diets on Weight Loss and Cardiovascular Risk Factors

Alain Nordmann et al. · Archives of Internal Medicine · 2006

DOI 10.1001/archinte.166.3.285

Meta-analysis · 5 studiesCited 975×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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