Research

Mixed

A carbohydrate-restricted diet (≤30g carbs/day) produces greater weight loss and greater improvements in triglyceride levels and insulin sensitivity compared to a calorie- and fat-restricted diet in severely obese subjects over six months.

If you are severely obese (BMI 35+) and have diabetes or metabolic syndrome, restricting carbohydrates to 30 grams per day for six months leads to significantly more weight loss and better triglyceride levels than a standard low-fat, calorie-restricted diet. However, adherence is difficult, with nearly half of participants dropping out, so strong support and counseling are essential.

ModerateSupportsMEDIUM confidence
Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet, with a relative improvement in insulin sensitivity and triglyceride levels, even after adjustment for the amount of weight lost.
Frederick F. Samaha et al. · New England Journal of Medicine · 2003

Why this rating

Randomized controlled trial with a large sample size (n=132) and severe obesity, but limited by high dropout rates (47-48%) and short duration (6 months).

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×
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DOI resolved against Crossref · corpus check 2026-06-10

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