Health benefits of late-onset metformin treatment every other week in mice

Intermittent use of metformin improves healthspan in old mice Chronic daily exposure to a high dose of metformin (e.g., 1% w/w) shortens lifespan of non-diabetic mice, although in the short term this treatment confers a similar pattern of gene expression and phenotypes consistent with the benefits of caloric restriction. A team of researchers led by Rafael de Cabo at the National Institute on Aging, NIH tested whether a strategy of intermittent 1% metformin treatment in old mice alters the course of aging and avoids toxicity. They found that when metformin was given every-other-week, it significantly improved insulin sensitivity and reduced age-associated liver lesions without having a negative impact on maximum lifespan in male mice. The absence of adverse outcomes associated with the use of 1% metformin in old mice has clinical translatability into the biology of aging in humans.