What to watch with MTHFR and stress?

MTHFR variants (especially C677T) reduce the conversion of folic acid to its active form, impairing methylation. Under stress, the body demands more methyl groups for neurotransmitter synthesis and cortisol clearance. Watch for adequate intake of methylfolate (5-MTHF), methylcobalamin (B12), and vitamin B6. Avoid high-dose unmethylated folic acid, which can accumulate. A DNA test alone is not diagnostic—homocysteine levels are more actionable. Evidence linking MTHFR directly to stress response is moderate; effects are largely indirect via homocysteine and methylation pathways.