What to watch with FUT2 and stress?

FUT2 (fucosyltransferase 2) determines secretor status and influences vitamin B12 absorption and gut microbiome composition. B12 deficiency can exacerbate stress symptoms such as fatigue, irritability, and poor concentration. Through the gut-brain axis, altered gut microbiota may also affect stress regulation. However, direct evidence linking FUT2 variants to stress susceptibility is weak. Most findings are mechanistic or observational, not from controlled human trials. Genetic testing alone is insufficient for stress management recommendations. A more practical approach includes ensuring adequate B12 intake (especially for non-secretors), stress reduction techniques, and clinical assessment if deficiency is suspected. Be cautious: effect sizes are small and clinical utility remains unclear.