Scientifically Speaking | Could a common diabetes drug slow down ageing?

Metformin is not a new drug, but recently there’s been quite a bit of buzz around its potential anti-ageing effect. Metformin is available widely around the world in generic form. It has been a trusted medication for managing type 2 diabetes since the 1950s. Originally derived from a plant called Goat’s Rue, it helps control blood sugar levels. However, recent research suggests that metformin might also play a role in slowing down the ageing process.

Doctors have noticed that diabetic patients taking metformin not only manage their blood sugar, but also seem to have lower rates of age-related diseases like heart disease, cancer, and cognitive decline. These observations sparked curiosity among scientists. Could metformin have protective effects that extend beyond diabetes?
Since metformin was given to diabetic patients, doctors were not sure if the supposed anti-ageing effects would also be observed in people who didn’t have diabetes. Untangling the effects of the drug from successfully treating diabetes also needed to be shown.
Studies in animals provided some early positive signs. Mice, flies, and worms given metformin often lived longer and showed signs of delayed ageing. These findings led researchers to consider the possibility that metformin might influence how ageing occurs.
Now, a study published in the scientific journal Cell reports that metformin slows ageing in male cynomolgus monkeys, a species closely related to humans. Over nearly four years, scientists administered metformin to a group of these monkeys and monitored them extensively. They collected tissue samples, performed brain scans, and conducted physical and cognitive tests.
The results were striking. Metformin appears to slow biological ageing in organs like the kidneys, lungs, and skin. It also has a major effect on the brain. Some monkeys showed neural activity resembling that of much younger monkeys. This suggests that metformin might keep the brain healthy and improve how it works.
Researchers discovered that metformin activates cells producing a protein called Nrf2, which protects against cellular damage from inflammation. This action might explain metformin’s protective effects on the brain.
The study did have some limits. It only included male monkeys and not many of them. Despite this, the findings are very promising. They suggest that metformin could slow ageing in primates, not just smaller animals. This is important because primates are closer to humans.
The promising results from animal studies and observational data in humans have set the stage for more rigorous research. Scientists are calling for larger, longer-term studies, including those with diverse populations and both genders.
To explore the possible real-world use of metformin beyond lab monkeys, scientists have initiated the TAME (Targeting Ageing with Metformin) Trial in people. This large-scale clinical study will try to find out if metformin can extend the period of life spent in good health, known as the “health span,” in humans.
So far, funding the TAME Trial has not been easy. Since metformin is a generic drug, there’s little financial incentive for pharmaceutical companies to support expensive trials. Despite its promise, the lack of patent protection means that future profits are limited, making it harder to secure investment for research.
Researchers are also delving deeper into how metformin works at the molecular level. They are studying how metformin influences cells to make energy and might clean up damaged parts of cells, which are processes that play a role in ageing. Understanding its impact on processes like inflammation, oxidative stress, and gut microbiota might unlock new ways to stave off age-related diseases.
In the meantime, the buzz around metformin’s potential has caught the attention of biohackers and some in the wellness community. Eager to reap its possible anti-ageing benefits, some people without diabetes have started taking metformin off-label. They hope to delay ageing and prevent age-related diseases, even though proof in humans is still lacking.
It’s never good to take any prescription drug without an actual prescription from a certified medical professional and for any purpose than for which it was originally intended, of course. Without comprehensive clinical trials confirming metformin’s safety and effectiveness for anti-ageing in healthy individuals, taking it could very well carry unknown health risks.
What does all this mean? Metformin remains a drug for diabetes. While its potential is promising, there’s a lot that we still need to learn before we can call it an anti-ageing wonder drug.
Anirban Mahapatra is a scientist and author, most recently of the popular science book, When The Drugs Don’t Work: The Hidden Pandemic That Could End Medicine. The views expressed are personal.