Methylfolate versus folic acid for MTHFR polymorphisms

Methylfolate is a very expensive pharma-patented ingredient in a supplemental form that is not generally required by people. Even those with genetic polymorphisms can convert folic acid to methylfolate, though less efficiently due to their genetic differences, and still benefit from folic acid supplementation. 

Since a main concern with MTHFR polymorphisms is the production of less active forms of the MTHFR enzyme due to genetically driven variations in its composition (such as the substitution of alanine with valine), the polymorphisms are most noted for increasing the need for folates (of any form, rather than a particular form). This is because higher quantities of these weaker MTHFR enzymes are needed to compensate for their lower activity levels and methylfolate is a cofactor in the enzyme production, so more dietary folic acid or folates are also needed. 

The medical literature on folic acid has been misrepresented on the Internet to falsely imply that folic acid will not work in individuals with MTHFR polymorphisms. But even people with the most severe polymorphisms can still convert folic acid to methylfolate and eliminate signs of folate insufficiency, particularly high homocysteine levels, according to clinical trials. Here is one example where increasing folic acid intake for individuals with these polymorphisms resolved the problem of high homocysteine levels caused by their weaker MTHFR enzymes:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5601299

The folic acid was converted to methylfolate and utilized by these study subjects to make more of these enzymes, which is needed to resolve the health concerns over high homocysteine levels, despite the subjects having polymorphisms that cause weaker versions of the enzymes to be produced. 

The CDC is even more direct, reporting, “You might have read or heard that folic acid is not safe if you have one or two copies of the MTHFR C677T variant. This is not true. Even if you have one or two copies of the MTHFR C677T variant, your body can safely and effectively process the different types of folate, including folic acid.” 

https://www.cdc.gov/ncbddd/folicacid/mthfr-gene-and-folic-acid.htm

So the widespread myth that people with MTHFR polymorphisms cannot process folic acid has been disproven in authoritative research showing that they actually need to increase folic acid intake (or methylfolate intake) to produce enough of the weaker enzymes to resolve the health concerns, including elevated homocysteine levels and potential neural tube defects in their offspring.