Research

Hormonal

Metformin's effectiveness in preventing diabetes decreases with increasing age, showing a trend toward higher diabetes incidence in older adults (60-85 years) compared to younger adults, potentially due to age-related differences in insulin secretion and hepatic glucose production.

If you are over 60 and considering metformin for diabetes prevention, be aware that it may be less effective than in younger people. The study suggests lifestyle changes (diet and exercise) are a much stronger preventive tool for older adults. Metformin might still be useful for treating established diabetes, but for prevention, lifestyle modification offers superior protection.

GoodQualifiesMEDIUM confidence
The metformin group showed a trend toward higher diabetes incidence among older participants (6.7, 7.7, and 9.3 cases per 100 person-years in the 25–44, 45–59, and 60–85 year age groups, respectively; ptrend ¼ .07)... diabetes risk increased with age (hazard ratio [age 60–85 vs 25–44] 1.63, p ¼ .02), after adjusting for the greater weight loss in the 60–85 year age group.
Jill Crandall et al. · The Journals of Gerontology Series A · 2006

Why this rating

Based on the same high-quality RCT (DPP), but the trend for metformin was of 'borderline significance' (p=.07) and hazard ratios were attenuated after adjustment.

Source

The Influence of Age on the Effects of Lifestyle Modification and Metformin in Prevention of Diabetes

Jill Crandall et al. · The Journals of Gerontology Series A · 2006

DOI 10.1093/gerona/61.10.1075

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

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