Research

Hormonal

Protracted metformin therapy (1500-2550 mg/day) induces significant weight loss in obese women with PCOS, with higher doses (2550 mg) yielding greater weight reduction in moderately obese patients (BMI 30-37) compared to lower doses.

If you have PCOS and are overweight, metformin can help you lose weight, especially if you take a higher dose (around 2550 mg/day). However, this benefit is most clear if your BMI is between 30 and 37. If you are morbidly obese, higher doses may not give you more weight loss than lower doses. Be prepared for potential stomach issues, which are common.

GoodQualifiesHIGH confidence
Intention to treat analyses showed significant weight loss in both dose groups. Only the obese subgroup showed a dose relationship (1.5 and 3.6 kg in 1500- and 2550-mg groups, respectively; P < 0.04).
L Harborne et al. · The Journal of Clinical Endocrinology & Metabolism · 2005

Why this rating

Randomized controlled trial with intention-to-treat analysis, though lacking a placebo group.

Source

Metformin and Weight Loss in Obese Women with Polycystic Ovary Syndrome: Comparison of Doses

L Harborne et al. · The Journal of Clinical Endocrinology & Metabolism · 2005

DOI 10.1210/jc.2004-2283

rct · n=83Cited 167×
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DOI resolved against Crossref · corpus check 2026-06-10

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