What should I know about MTHFR Basis?

MTHFR variants (e.g., C677T, A1298C) are common and reduce the enzyme's ability to convert folic acid into active methylfolate. However, clinical relevance is often overstated. The key biomarker is blood homocysteine: only if elevated might methylfolate supplementation (plus B12 and B6) be considered. Many carriers have normal homocysteine and do not require special supplements. Acting solely on a DNA test is not evidence-based. High-dose methylfolate can also mask B12 deficiency if untreated. Evidence comes from observational studies and GWAS; robust interventional trials are lacking. A physician should measure homocysteine, B12, and folate before any supplementation. Consumer DNA tests tend to overhype single-gene effects – MTHFR is not a 'disease gene' but part of a complex methylation network.