Research

Hormonal

In severely obese subjects, a carbohydrate-restricted diet improves insulin sensitivity independently of the amount of weight lost, compared to a low-fat diet.

For non-diabetic severely obese individuals, cutting carbs to 30g/day improves how your body handles insulin, even if you don't lose as much weight as someone on a low-fat diet. This suggests a direct metabolic benefit to carb restriction beyond just burning fewer calories.

ModerateSupportsMEDIUM confidence
In a model adjusted for the amount of weight lost and base-line variables, assignment to the low-carbohydrate diet (P = 0.01) and the amount of weight lost (P<0.001) were each independent predictors of an improvement in insulin sensitivity.
Frederick F. Samaha et al. · New England Journal of Medicine · 2003

Why this rating

RCT design, but insulin sensitivity was only measured in non-diabetic subjects, limiting generalizability to the diabetic population (39% of cohort).

Source

A Low-Carbohydrate as Compared with a Low-Fat Diet in Severe Obesity

Frederick F. Samaha et al. · New England Journal of Medicine · 2003

DOI 10.1056/nejmoa022637

rct · n=132Cited 1,269×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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