What to watch with TCF7L2 and longevity?

The TCF7L2 rs7903146 T allele is a well-established risk factor for type 2 diabetes (OR ~1.54 per copy). For longevity, preventing diabetes and its complications is crucial. FOXO3 variants (e.g., rs2802292) have been linked to longevity in some studies, but the evidence is moderate. No direct gene-gene interaction between TCF7L2 and FOXO3 is known. Carriers of the T risk allele should prioritize glycemic control, healthy diet, and regular exercise. The risk increase is modest; lifestyle factors are far more influential. Be cautious of commercial claims that single genes determine lifespan. Consult a healthcare provider for personalized prevention strategies.