What is MTHFR?

Methylenetetrahydrofolate Reductase

Did you know that more than half of the world’s population has an MTHFR gene mutation?!

If you’re visiting us, chances are you’ve heard of MTHFR. Perhaps you or someone you love has recently discovered that an MTHFR variant is responsible for many years of unexplained health issues.

We can’t all be scientists, and we don’t always have the time or energy to dive into the minutiae on every subject, including MTHFR.

That’s where Methyl-Life® comes in!
We’ve done the research. We’ve read the books, talked to the doctors, and taken the deep dive. We’ve done it all so that we can deliver you the highest-quality supplements, but also so that we can share what we’ve learned and build a community around our shared health concerns and needs. 

A few examples of informational topics we cover on our site are: MTHFR Symptoms, Treating MTHFR, MTHFR and Methylation and more ... But before we get to all that, let’s make sure we're on the same page…

What is MTHFR, and what does it mean to have an MTHFR mutation or MTHFR deficiency?

MTHFR stands for Methylenetetrahydrofolate Reductase. It is a key regulatory enzyme in the metabolism of folate. It also refers to a specific gene that plays a major role in the body’s methylation process. Both the enzyme and the gene have the same name, MTHFR.  

However, when people talk about “MTHFR,” they’re usually not talking about either the enzyme or the gene, precisely. They are more typically referring to one of the two common MTHFR gene mutations or that causes the enzyme to become imperfect and much less effective in the body. 

The gene’s role is very complex, and MTHFR gene polymorphisms (or variants) have been the focus of recent discoveries uncovered by the Human Genome Project. In fact, thanks to the Human Genome Project, we now know that there are as many as 60+ variants of the MTHFR gene! The two most well-known 677 & 1298 were discovered in 1995 and 2001, respectively. 

MTHFR SNPs (or Single Nucleotide Polymorphisms) are often referred to as ‘mutations’ or ‘defects’ because of the problems they cause in the body. MTHFR most often refers to the two most well-known genetic SNPs (677 and 1298) that inhibit the ability of the body to methylate (or convert folate into L-5-Methyltetrahydrofolate - which the body requires for absorption and direct use). Instead, these mutations make imperfect folate coenzymes which don't work properly to generate all of the important downstream processes like: 

  • Synthesize DNA to regulate gene expression
  • Develop a healthy central nervous system
  • Promote balanced neurotransmitters like serotonin
  • Protect neurons by generating myelin
  • Regulate homocysteine levels for cardiovascular health
  • Produce glutathione for detoxification
  • Support healthy pregnancy and fetal development
  • And many more ...

At the crux of it, the body has trouble converting folate from the food we eat into methylfolate (L-5-MTHF), the bioavailable folate enzyme needed to optimize health. The truth is our cells cannot actually use folic acid directly. Upon ingestion, folate must go through a 4-step process (called a metabolic pathway) in order to be converted into methylfolate, which is the “active” or usable form of folate that our body’s cells require.

The MTHFR gene defect inhibits this metabolic pathway and prevents our cells from getting the methylfolate they need.
Even though we know that there are more than 60 possible MTHFR gene mutations, most of the MTHFR Blood Tests used today only check for the two SNPs that are considered “common”: 677 and 1298.

Since we all get one copy of the MTHFR gene from each parent, a person could have many different combinations, as well as the problems that go with it. In fact, it’s very rare, but some folks can have 3 mutations (a double mutation on one gene and a single mutation on the other), or even 4 mutations in extraordinarily rare cases.

Understanding MTHFR Test Results

Quick reference chart listing MTHFR gene mutation combinations & potential health issues related.


With or without knowing your specific MTHFR mutation status, however, Methyl-Life® can still help you determine what nutritional supplements can help you feel better. Check out our:

What happens if the cells don’t get enough methylfolate to keep your body healthy?