Myths vs facts: MTHFR and sleep

The question of myths vs. facts regarding MTHFR and sleep is not directly addressed in the provided context. MTHFR (methylenetetrahydrofolate reductase) is involved in folate metabolism and indirectly influences neurotransmitter synthesis via homocysteine regulation. Popular claims link MTHFR variants (e.g., C677T) to sleep disturbances, but the scientific evidence is weak. No robust studies demonstrate a causal relationship between common MTHFR polymorphisms and sleep quality. Effects are small, context-dependent, and overshadowed by diet, lifestyle, and other genes. A direct-to-consumer DNA test for MTHFR does not provide clinically actionable information for sleep. Supplements like methylfolate are often recommended without proof; uncritical use may carry risks (e.g., masking B12 deficiency). Conclusion: The claim that MTHFR variants are a major cause of sleep problems is a myth. The fact is that MTHFR may play a minor, indirect role, but it should not be used as a sole explanation or basis for intervention. Evidence: mechanistic, not clinically validated.