Evidence check: FADS1 in the context of longevity

FADS1 variants (e.g., rs174547) are involved in fatty acid desaturation, affecting the conversion of linoleic acid to arachidonic acid and alpha-linolenic acid to EPA/DHA. GWAS have linked certain alleles to altered blood lipid profiles, inflammatory markers, and, in some observational studies, to longevity. However, effect sizes are small and lifestyle factors (diet, exercise, smoking) dominate. No randomized controlled trials directly demonstrate that FADS1 genotype determines lifespan. Direct-to-consumer tests often overstate the importance of single SNPs. A balanced diet rich in omega-3s (e.g., fatty fish, flaxseed) is generally beneficial, but tailoring intake solely based on FADS1 is not strongly supported. Be cautious of exaggerated longevity claims. Evidence: human-moderate (GWAS, observational).