Research

Hormonal

Metformin administration (up to 2500 mg/day) produces significant weight loss (average 5.8 kg) in non-diabetic obese individuals, with the magnitude of weight loss positively correlated with the degree of baseline insulin resistance.

If you are obese but do not have diabetes, metformin can help you lose weight, especially if you have high insulin resistance. The typical dose is 1500-2500 mg daily, but you must start low (500 mg) and increase it slowly over weeks to avoid stomach upset. This works best if you do not simultaneously try to diet or change your exercise habits, as the drug's metabolic effects are the primary driver.

ModerateQualifiesMEDIUM confidence
The mean weight loss in the metformin treated group was 5.8 ± 7.0 kg (5.6 ± 6.5 %)... Patients with severe insulin resistance lost significantly more weight as compared to insulin sensitive patients.
C. Seifarth et al. · Experimental and Clinical Endocrinology & Diabetes · 2012

Why this rating

Observational/naturalistic study with a non-randomized control group; lacks blinding.

Source

Effectiveness of Metformin on Weight Loss in Non-Diabetic Individuals with Obesity

C. Seifarth et al. · Experimental and Clinical Endocrinology & Diabetes · 2012

DOI 10.1055/s-0032-1327734

cohort · n=199Cited 254×
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DOI resolved against Crossref · corpus check 2026-06-10

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