Research

Energy balance

Low-carbohydrate and low-fat diets produce statistically similar and significant weight loss in overweight and obese adults, with no clinically meaningful difference between named diet brands.

Stop searching for the single 'best' diet. Both low-carb and low-fat diets work equally well for weight loss if you stick with them. Focus on choosing a dietary pattern you can maintain for at least 6-12 months, rather than trying to outsmart the system with a specific brand or macronutrient ratio.

ModerateQualifiesMEDIUM confidence
Significant weight loss was observed with any low-carbohydrate or low-fat diet. Weight loss differences between individual named diets were small. This supports the practice of recommending any diet that a patient will adhere to in order to lose weight.
Bradley C. Johnston et al. · JAMA · 2014

Why this rating

The paper uses a Bayesian network meta-analysis of 48 RCTs, but GRADE assessment rated confidence as moderate to low due to risk of bias and imprecision.

Source

Comparison of Weight Loss Among Named Diet Programs in Overweight and Obese Adults

Bradley C. Johnston et al. · JAMA · 2014

DOI 10.1001/jama.2014.10397

Meta-analysis · 48 studiesCited 695×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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