What role does MTHFR play in Schlaf?

MTHFR encodes methylenetetrahydrofolate reductase, a key enzyme in methylation. Methylation affects neurotransmitter synthesis (serotonin, dopamine) that regulate sleep-wake cycles. Some studies link MTHFR variants (especially C677T) to sleep disorders like insomnia, sleep apnea, or restless legs syndrome, but effect sizes are small and findings inconsistent. Evidence is primarily mechanistic and from association studies, not clinical trials. A DNA test alone cannot diagnose sleep problems. If a variant is present, ensuring adequate folate, B12, and B6 may lower homocysteine, but direct sleep benefits are unproven. The clinical utility is limited; lifestyle, stress, and sleep hygiene are far more impactful.