A new study suggests that metformin, a widely used drug, may have additional benefits beyond its current applications. Research conducted this month indicates that metformin could potentially slow aging in the body and brain of monkeys. Further studies in humans will be required to confirm these findings, but the drug is already both affordable and widely accessible.
Metformin has long been an essential medication for treating type 2 diabetes, recognized for its safety and efficacy, and listed on the World Health Organization’s list of essential medicines. The drug helps lower blood sugar levels in these patients. It has also been employed off-label for modest weight loss and to manage polycystic ovary syndrome (PCOS) symptoms. Over time, some research has hinted that reducing inflammation by metformin could offer additional health benefits. Notably, studies have suggested that metformin may improve brain function and slow cognitive decline in elderly patients. Although it may not directly prolong lifespan, metformin could enhance "healthspan," the period of life spent in good health.
Much existing evidence for the anti-aging properties of metformin comes from indirect observational studies or research on less closely related animals, such as rodents. However, a recent study published in the journal Cell by a team of researchers in China has addressed this gap. The scientists conducted a 40-month study involving adult male cynomolgus monkeys (Macaca fascicularis), which corresponds to approximately 13 years of human life. During this period, 12 older monkeys were administered metformin, and their health was compared to two control groups: 16 older monkeys and 18 younger to middle-aged monkeys not given the drug.
Through a comprehensive set of tests, including brain scans, the researchers modeled the expected and actual biological age of the monkeys’ organs. Monkeys given metformin exhibited slower aging signs, especially in their livers and brains, compared to elderly monkeys not on the drug. The researchers estimated that metformin made these monkeys’ brains six years younger, a change that might equate to around 18 years in humans.
The research team stated, “Our research pioneers the systemic reduction of multi-dimensional biological age in primates through metformin, paving the way for advancing pharmaceutical strategies against human aging.”
This study represents the first direct investigation into metformin’s anti-aging potential in primates. However, the study’s small sample size and the biological differences between cynomolgus monkeys and humans warrant cautious interpretation of the results. Further research is necessary to ascertain the drug’s effects in humans.
Researchers have already commenced work on a Phase II trial, in collaboration with the company Merck, to test metformin as an anti-aging drug in 120 participants. In addition to these findings, metformin has shown promise in another context. An NIH-sponsored study recently discovered that people taking metformin for diabetes were less likely to die from COVID-19 or develop long COVID compared to those using other diabetes medications. This adds to the growing body of evidence suggesting metformin’s potential as a valuable treatment for long COVID.
