What is the MTHFR Gene, and Why Does it Matter?

It’s time to talk about folate, the MTHFR gene, and the genetic mutation that could inhibit your body's use of folate.

By Dr. Kenosha Gleaton

Chances are you’re familiar with the benefits of folate supplementation for fertility and throughout pregnancy, but what good is a supplement if your body can’t utilize it?! A large percentile of the population has a mutation of the MTHFR (methylenetetrahydrofolate reductase) gene that impacts the breakdown of folate. And since folate is imperative for the developing fetus, this is a really big deal. Fortunately, there are options available to ensure adequate folate intake for you and your baby, even with the MTHFR variant.

What is MTHF?

MTHF folate, also known as levomefolic acid, L-5-MTHF, L-5-methyltetrahydrofolate, (6S)-5-methyltetrahydrofolate, and (6S)-5-MTHF is a folate often found in food and an important component of prenatal vitamins. Folate is recommended by the CDC and ACOG for all women of childbearing age to reduce the risk of spina bifida, decrease pregnancy loss, protect the body from environmental toxins, and increase IVF outcomes.

While there are many forms of folate, MTHF is considered the most beneficial, since it is immediately absorbed and utilized by the body. Other types of folate, like folic acid, require conversion into MTHF first before being utilized. But what if your body can’t convert folic acid into MTHF? And how would you even know? Keep reading…

The MTHFR gene and variant

Methylenetetrahydrofolate reductase (MTHFR) is a key regulatory enzyme in folate metabolism; essentially, MTHFR is what converts folic acid into MTHF. In layman’s terms, the presence of the MTHFR gene is what allows the body to use folic acid for all the positives mentioned above. About a quarter of the population has a variant of this gene, and the MTHFR mutation makes it extremely difficult to metabolize folic acid, increasing the risk of pregnancy loss, neural tube defects, damage from environmental toxins, and more.

How the MTHFR gene mutation affects pregnant women

So what are the effects of the MTHFR gene mutation on fertility and pregnancy? If a pregnant woman has this gene mutation, this means her body's ability to metabolize and use folate is inhibited. If she’s taking folic acid or some form of folate that isn’t MTHF folate, she’s in danger of a pregnancy complication, such as neural tube defects, pregnancy loss, higher fecundability (a harder time becoming pregnant), and more.

If a pregnant woman has this gene mutation, this means her body's ability to metabolize and utilize folate is inhibited.

How pregnant women can manage an MTHFR gene mutation

Isn’t there a way to test if you have this MTHFR mutation? Yes, technically there is a test that requires blood work to determine if you have the MTHFR gene, but there is speculation on whether the test will give accurate or useful information to asymptomatic people. Truth is, there isn’t much to be done if you do have the gene mutation, but most preliminary research suggests MTHF supplementation will still benefit you more than folic acid supplementation would. Make sure you’re following the ACOG’s guidelines on folate supplementation, 400 mcg when trying to conceive, and 600 mcg when pregnant. And although you can increase folate levels through foods such as leafy greens, legumes, asparagus, and brussel sprouts, the amounts are not consistent. Food processing, including chopping and cooking, can reduce the amount of folate availability.

Prenatal vitamins for women with a MTHFR gene mutation

For women with this gene mutation, it’s critical to supplement a healthy diet with prenatal vitamins that include bioavailable MTHF folate rather than folic acid. One of the key differences between folate vs. folic acid is that folate is more highly bioavailable, meaning it can be immediately absorbed by the body. Choosing a high-quality prenatal containing MTHF folate can increase the chances of your body benefiting from folate supplementation and encouraging healthier pregnancy outcomes.

For women with this gene mutation, it’s critical to supplement a healthy diet with prenatal vitamins that include bioavailable MTHF folate rather than folic acid.

Choose prenatals formulated with MTHF folate

Take home points: Our bodies need essential nutrients such as folate to properly develop and grow a little human. Unfortunately, nearly 25% of the population has a gene mutation that makes it difficult to properly use folic acid and folate found in some prenatal supplements. Ensuring your prenatal vitamins have MTHF folate rather than folic acid will increase your chances of absorbing and using folate.