Research

Mixed

Long-term metformin use (up to 10 years) produces modest but durable weight loss and waist circumference reduction in overweight/obese individuals with impaired glucose tolerance, with effects directly proportional to adherence.

If you have prediabetes or are overweight with elevated blood sugar, metformin can help you lose a modest amount of weight (about 2% of body weight) and keep it off for years. This benefit is only realized if you take the medication consistently. Start with a low dose to minimize stomach upset, which usually goes away. The weight loss comes from fat, not muscle, and works alongside lifestyle changes like diet and exercise.

GoodSupportsHIGH confidence
Metformin used for diabetes prevention is safe and well tolerated. Weight loss is related to adherence to metformin and is durable for at least 10 years of treatment.
The Diabetes Prevention Program Research Group · Diabetes Care · 2012

Why this rating

Large randomized controlled trial (DPP) with long-term open-label follow-up (DPPOS), high adherence rates, and rigorous statistical analysis.

Source

Long-Term Safety, Tolerability, and Weight Loss Associated With Metformin in the Diabetes Prevention Program Outcomes Study

The Diabetes Prevention Program Research Group · Diabetes Care · 2012

DOI 10.2337/dc11-1299

rct · n=2155Cited 491×
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DOI resolved against Crossref · corpus check 2026-06-10

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