Highlights
– Large randomized follow-up from the Diabetes Prevention Program found no statistically significant reduction in overall cancer incidence with metformin over 21 years (HR 0.90, 95% CI 0.73–1.10).
– Randomized perinatal and complementary animal studies show no effect of metformin on placental ageing markers (telomere length, methylation, histology).
– Metformin did not change IgG GlycanAge index in a middle‑aged male cohort, whereas testosterone did; suggesting limited impact of metformin on this biomarker of biological age.
– Metformin is associated with reproducible changes in the gut microbiome (notably Akkermansia muciniphila enrichment) and plasma metabolites; in two cohorts this microbiome/metabolite signature correlated with better memory performance in men.
