MTHFR and hyperhomocysteinemia: In addition, MMS with 800 μg folic acid increased RBC folate to levels protective against NTDs (>906 nmol/L) in 4 weeks; increased levels of vitamins B2, B6, and B12; and lowered the risk of hyperhomocysteinemia in all women, including those with MTHFR genotype mutations that can affect their ability to process folic acid.