What to watch with FADS1 and gut health?

FADS1 encodes delta-5 desaturase, a key enzyme in the conversion of polyunsaturated fatty acids (PUFAs) like omega-3 and omega-6. Variants in FADS1 can alter the efficiency of endogenous EPA and DHA synthesis. For gut health, this matters because these fatty acids are precursors to eicosanoids that regulate inflammation. Reduced desaturase activity might theoretically shift the balance toward pro-inflammatory mediators, potentially affecting intestinal barrier function and the microbiome. However, direct human evidence linking FADS1 SNPs to gut health outcomes is limited – most data come from mechanistic studies or associations with systemic inflammatory markers. Diet (intake of preformed EPA/DHA from fish or algae) has a far greater impact than genetics. A consumer DNA test cannot diagnose or guide gut health interventions based on FADS1 alone. Practical advice: focus on overall omega-3 status, fiber intake, and a diverse microbiome rather than a single gene variant.