What to watch with FUT2 and longevity?

FUT2 (fucosyltransferase 2) determines secretor status and influences vitamin B12 absorption and gut microbiome composition. A non-functional FUT2 allele (non-secretor) is linked to lower B12 levels, which over time may increase risk for cognitive decline and anemia – both factors that can reduce healthspan. Non-secretors also tend to have a less diverse microbiome with fewer Bifidobacteria, potentially promoting low-grade inflammation. However, direct evidence connecting FUT2 to longevity is weak: no prospective studies show that FUT2 variants predict longer lifespan. The effects are indirect and heavily modulated by diet, lifestyle, and other genetic factors. A consumer DNA test can report your FUT2 status, but it cannot predict your longevity. Practical takeaway: if you are a non-secretor, ensure adequate B12 intake (supplements or fortified foods) and support gut health with prebiotic fibers. Evidence grade: mechanistic/unclear.