Key points from article :
A recent study explored the effects of metformin, a diabetes medication, on ageing monkeys. Researchers treated middle-aged cynomolgus macaques with metformin for over three years, comparing them to a control group. The study, published in Cell, claimed metformin helped preserve brain structure, improved cognitive function, and slowed biological ageing by over six years based on an age clock designed for the monkeys.
The treated monkeys gained less weight and showed fewer signs of diabetes compared to untreated controls. Monkeys in the control group became significantly obese and diabetic during the study, while metformin-treated ones remained healthier. The authors highlighted these outcomes as evidence that metformin can target fundamental ageing processes.
However, the study had several flaws that call its findings into question. Only twelve middle-aged monkeys were involved, split equally into treated and untreated groups, which is too small for reliable conclusions. There were also no baseline measurements for key health markers like brain function and metabolism, which complicates any conclusions about changes over time. Without knowing where the monkeys started, it’s unclear whether metformin truly prevented decline or if treated monkeys just happened to be in better health initially.
The study's findings could also reflect metformin’s known impact on obesity and diabetes, rather than its direct effect on ageing itself. For instance, the control monkeys became obese and diabetic, while metformin treatment protected against these conditions. This suggests that the observed cognitive and ageing effects could be due to better metabolic health rather than an actual anti-ageing impact.
Moreover, the age clock used to measure changes in biological age was derived from the same monkeys involved in the study, introducing possible biases. The lack of random assignment of monkeys, absence of blinding, and vague details about the animals' backgrounds all weaken the reliability of the findings.
In summary, while metformin had positive effects on weight and diabetes, its role as a longevity therapeutic remains questionable, needing further well-controlled studies for validation.
The study was led by researchers from University of Chinese Academy of Sciences and is published in the journal Cell.
