Methylfolate vs folic acid: what is the difference?

The three folates

It helps to keep the names straight, because they get used loosely. Folate is the natural form found in foods like leafy greens, pulses and liver. Folic acid is a synthetic, very stable form used in supplements and in fortified flour and cereals, and it is the form used in almost all the research. Methylfolate, sometimes written 5-MTHF, is the form your body actually uses once it has done a little conversion work. They are three versions of the same vitamin.

How your body converts them

Your body turns folic acid into the active form through a few enzyme steps. For most people this happens without any trouble. You will read a lot online about the MTHFR gene, which codes for one of those enzymes. Some variants of it are genuinely common, and they can make the conversion a bit less efficient. What the evidence does not support is the leap from "less efficient" to "you cannot use folic acid", which is where a lot of marketing goes. Most people with a common MTHFR variant still convert folic acid perfectly well.

What an MTHFR variant means

If a test has told you that you carry an MTHFR variant, it is easy to be alarmed by what you find online. A variant is common and it is not a diagnosis. On its own it is rarely a reason to change what you take. Some people prefer to take methylfolate, the already-active form, so their body has less conversion to do. That is a reasonable preference. It is not the same as evidence that methylfolate is medically better for everyone, which does not exist.

Which should you choose?

For general use, either form is fine, and folic acid has the longer track record. Some people simply prefer the active form, and our prenatal and our B complex both use methylfolate, as L-5-methylfolate, for that reason. If you are pregnant or trying to conceive, read this next to our pregnancy guide, because there the recommendation is specific and the amount matters as much as the form.