Metformin’s Effect on Biological Ageing in Prediabetes: New 2026 Indian Study

#metformin #prediabetes #ageing Metformin increased leukocyte telomere length, telomerase activity and SIRT1 expression in Indian adults with prediabetes, suggesting potential anti-ageing effects beyond glycaemic control, a recent Indian study has reported. This research is published in the September 2026 issue of Mechanisms of Ageing and Development. The study was conducted as a double-blind, randomized controlled trial that included 127 Indian adults aged 30–60 years with prediabetes, randomised to metformin 500 mg twice daily (n=63) or placebo (n=64) for 24 weeks, alongside lifestyle counselling. 112 participants (56 per group) completed the study. The primary outcomes included leukocyte telomere length (LTL), telomerase activity (TA), and expression of longevity-associated genes SIRT1, p66Shc, p53, and mTOR. Secondary outcomes included anthropometric and metabolic parameters. Some of the key results of the study are: • The metformin group showed a 29.6% increase in leukocyte telomere length (LTL) (+0.247 ± 0.298) over six months, compared with a 4.4% increase (+0.036 ± 0.068) with placebo. • Metformin increased telomerase activity by 39.25% (+0.528 ± 0.412) over six months, while placebo showed a 1.41% decrease (−0.019 ± 0.279). • Metformin increased SIRT1 expression by 30.41% (+0.249 ± 0.535), compared with a 3.54% increase (+0.029 ± 0.097) with placebo. The between-group difference was significant for all the above parameters. • Metformin increased mTOR expression by 51.82% (+0.570 ± 1.418), compared with a 14.21% reduction (−0.162 ± 0.292) with placebo. The between-group difference was significant (p=0.0004). • No significant between-group differences were observed in p66Shc (p=0.6194) or p53 (p=0.8376) expression. • No significant changes were observed in biochemical or anthropometric parameters, including body weight, BMI, waist/hip circumference, glycaemic measures and lipid profile. These findings suggest that metformin exerts potent, pleiotropic gero-protective effects independent of glycemic control, highlighting the need for further exploration in high-risk populations like Asian Indians, who are uniquely susceptible to premature biological senescence. While longer-duration trials are needed, this novel research provides a significant molecular rationale for considering metformin to extend health span and mitigate accelerated aging, when indicated.