Can FOXO3 help with longevity?

FOXO3 variants are associated with longevity in human studies, especially among centenarians. FOXO3 regulates stress resistance, DNA repair, and metabolism. However, evidence comes from observational and GWAS studies, not clinical trials. The effect size is small and lifestyle factors (diet, exercise) are more influential. A DNA test alone cannot predict individual lifespan. Caveat: No actionable clinical recommendation. Evidence: human-observational/gwas.