Metformin moved ageing markers, not metabolism - the prediabetes trial

Medical Dialogues · Article

In a 24-week double-blind randomised trial, 127 Indian adults aged 30-60 with prediabetes received metformin 500 mg twice daily or placebo, both with lifestyle counselling; 112 finished. The metformin group showed larger rises in leukocyte telomere length, telomerase activity and SIRT1 expression than placebo - while weight, waist measures, glucose control and lipids did not differ significantly between groups.

Key takeaways:

• The molecular markers moved without the metabolic ones: no significant between-group change in body weight, BMI, glycaemic measures or lipid profile over six months
• The picture is not uniformly youthful: mTOR expression also rose substantially on metformin, and two other tracked genes (p66Shc and p53) showed no significant difference
• Telomere length and gene expression are surrogates, not outcomes: nobody has shown that shifting them over 24 weeks changes disease, function or lifespan

Hype check: Proven - a randomised, blinded difference in telomere, telomerase and SIRT1 measures over 24 weeks in one prediabetes population. Promising - metformin as a geroprotective candidate in high-risk groups, pending longer trials with clinical endpoints. Marketing - any headline reading this as metformin reversing ageing; the trial measured blood markers only, in people with prediabetes, for six months.