Research

Energy balance

There is insufficient evidence to recommend low-carbohydrate diets for use longer than 90 days, for participants older than 50 years, or for diets providing 20 g/d or less of carbohydrates.

If you are over 50 or plan to follow a very low-carb diet (<20g) for more than 3 months, be aware that current scientific evidence is insufficient to confirm its safety or efficacy. Consult a healthcare provider before committing to these specific parameters.

GoodQualifiesLOW confidence
There is insufficient evidence to make recommendations for or against the use of low-carbohydrate diets, particularly among participants older than age 50 years, for use longer than 90 days, or for diets of 20 g/d or less of carbohydrates.
Dena M Bravata et al. · JAMA · 2003

Why this rating

Based on the lack of data in the included studies.

Source

Efficacy and Safety of Low-Carbohydrate Diets

Dena M Bravata et al. · JAMA · 2003

DOI 10.1001/jama.289.14.1837

Meta-analysis · 94 studiesCited 563×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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