Metformin mild supplementation improves health and survival of mice

Metformin, a commonly used drug prescribed to treat type-2 diabetes, has been found to extend health span and delay cancer incidence and progression. Here, we report that starting chronic treatment with low dose of metformin (0.1% w/w in diet) at one year of age extends health and lifespan in male mice, while a higher dose (1% w/w) was toxic. Treatment with low dose metformin mimicked some of the benefits of calorie restriction, such as improved physical performance, increased insulin sensitivity, and reduced LDL and cholesterol levels. At a molecular level, metformin increased AMP-activated protein kinase activity without attenuation of the mitochondrial electron transport chain activities. Metformin treatment resulted in lower chronic inflammation and increased antioxidant protection, suggesting that the ability of metformin to improve health of laboratory animals may stem from these factors. Our results support that metformin supplementation could be beneficial in extending health and lifespan in humans.