“Common MTHFR variants mean you need methylated vitamins.”
Common MTHFR variants do not mean you need methylated vitamins.
A common MTHFR result does not mean your body cannot handle regular folic acid, and it is not a reason to buy special methylated vitamins. If you could become pregnant, regular folic acid is the recommended choice.
If you could become pregnant, take a vitamin with 400 mcg of folic acid every day, whatever your MTHFR result.
Safety note: If you could become pregnant, do not stop or replace folic acid because of an MTHFR result: folic acid is the only form of folate shown to help prevent neural tube defects. Rare, severe MTHFR variants are different and need a doctor's or genetic counselor's advice.
Talk to a healthcare professional if: you have been told you have a rare, severe MTHFR variant, or you have a health condition and want to know whether you need more folic acid than the usual amount.
The CDC and a large double-blind trial show that people with common MTHFR variants still use folic acid and that their folate levels respond to it in the same way as everyone else's. Folic acid is the only form of folate shown to prevent neural tube defects, so the evidence firmly does not support a need for methylated vitamins.
Common MTHFR variants do not mean you need methylated vitamins. People with these variants can still use folic acid; some have slightly lower folate levels, but in a large trial folic acid raised their levels in the same way.
MTHFR variants are very common: more people in the United States carry one or two copies of the C677T variant than do not. The CDC says people with an MTHFR variant can process all types of folate, including folic acid, and that people with two copies (the TT type) have blood folate about 16% lower than people with none at the same folic acid intake. In a double-blind trial of 932 genotyped women in northern China given different folic acid doses for 6 months, the TT type had lower folate throughout, but the gene type did not significantly change how folate responded to the dose. Folic acid is the only form of folate shown to help prevent neural tube defects, which is why the CDC advises 400 mcg a day for anyone who could become pregnant, with or without an MTHFR variant.
- Centers for Disease Control and Prevention. MTHFR Gene Variant and Folic Acid Facts. cdc.gov. Updated July 16, 2026
- Crider KS, Zhu JH, Hao L, Yang QH, Yang TP, Gindler J, Maneval DR, Quinlivan EP, Li Z, Bailey LB, Berry RJ. MTHFR 677C->T genotype is associated with folate and homocysteine concentrations in a large, population-based, double-blind trial of folic acid supplementation. American Journal of Clinical Nutrition. 2011;93(6):1365-1372. DOI: 10.3945/ajcn.110.004671. PMID: 21508090