Lay opinion vs evidence: MTHFR Männer

The question of MTHFR in men is a classic case of lay opinion clashing with evidence. Popular health blogs and influencers often portray MTHFR variants as a 'genetic defect' requiring special methylfolate instead of folic acid – especially for men concerned about fertility or cardiovascular health. However, current guidelines (e.g., USPSTF 2023, PMID:37526720) explicitly recommend against routine MTHFR testing. The evidence shows that standard folic acid supplementation works equally well regardless of MTHFR genotype for most people. While certain MTHFR variants (like C677T) can modestly raise homocysteine levels, randomized controlled trials have found no clinical benefit from genotype-based supplementation. For men with elevated homocysteine, lifestyle factors – diet, exercise, smoking cessation – are far more impactful than any single gene variant. The marketing of MTHFR tests as a personalized health tool is not supported by robust science. Bottom line: No evidence supports routine MTHFR screening in men; folic acid remains the evidence-based standard.