Fact-Checking the Biohackers Who Claim Metformin is an Anti-Aging Wonder Drug

A recent review in the journal Aging has examined the potential anti-aging effects of the diabetes medication metformin. Researchers from Hamad Bin Khalifa University in Qatar reviewed cellular studies, animal model research, and human observational investigations to assess its impact. On a cellular level, metformin has been shown to increase autophagy (the process by which cells recycle damaged parts), boost mitochondrial production, and reduce oxidative stress.

It may also help with other negative aging hallmarks, such as deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence (when aging cells stop dividing), and more. Furthermore, there are associations between metformin and reduced epigenetic age acceleration.

However, the researchers caution that these molecular and cellular changes may not necessarily lead to an increased lifespan. In animal studies, metformin has shown more promise, with experiments involving roundworms and multiple mouse models indicating that the drug can lengthen lifespans. Male macaques have also demonstrated reduced aging markers in their tissues when given metformin.

In human observational studies, metformin has also been linked to better survival and healthier aging, although there are some caveats. Most subjects in these studies have been individuals with diabetes, and the endpoints of the investigations varied widely, from mortality to frailty, all lumped under the "aging" umbrella. This makes it difficult to determine if metformin is slowing aging or simply improving disease outcomes in certain groups.

Clinical trials have also been conducted, with mixed results. One study involving older people with metabolic syndromes found that metformin protected against diabetes but had no impact on cancer, cardiovascular disease, or mortality. Another trial involving 3,000 healthy older adults has been ongoing since 2017, but no results have been published yet.

The researchers conclude that the challenge moving forward will be to identify populations, biological pathways, and outcome measures through which metformin can meaningfully delay age-related functional decline, turning its metabolic benefits into actionable schemes for healthy aging.