You may have seen the abbreviation “MTHFR” pop up in recent health news. It might look like a curse word at first glance, but it actually has to do with a relatively common genetic mutation.
MTHFR stands for methylenetetrahydrofolate reductase. It’s getting attention due to a genetic mutation that may lead to high levels of homocysteine in the blood and low levels of folate and other vitamins.
There’s been concern that certain health issues are associated with MTHFR mutations, so testing has become more mainstream over the years.
People can have either one or two mutations (or neither) on the MTHFR gene. These mutations are often called variants. A variant is a part of the DNA of a gene that is commonly different (or varies) from person to person.
Having one variant (heterozygous) is unlikely to contribute to health issues. Some people believe having two mutations (homozygous) may lead to more serious problems. There are two variants (forms) of mutations that can occur on the MTHFR gene.
Specific variants are:
- C677T. Some 30 to 40 percent of the American population may have a mutation at gene position C677T. Some 25 percent of people of Hispanic descent, and 10 to 15 percent of Caucasian descent are homozygous (have two mutations) for this variant.
- A1298C. Around 20 percent of the American population may have a homozygous mutation at gene position A1298C.
- It’s also possible to acquire both C677T and A1298C mutations (one copy of each).
Gene mutations are inherited, which means you acquire them from your parents. At conception, you receive one copy of the MTHFR gene from each parent. If both have mutations, your risk is higher of having a homozygous mutation.
Symptoms vary from person to person and from variant to variant. If you do a quick internet search, you’ll likely find many websites claiming MTHFR directly causes a number of conditions.
Keep in mind that research around MTHFR and its effects is still evolving. Evidence linking most of these health conditions to MTHFR is currently lacking or has been disproven and should be taken with a grain of salt.
More than likely, unless you have problems or have testing done, you’ll never become aware of your MTHFR mutation status.
Conditions that have been proposed to be associated with MTHFR include:
- cardiovascular and thromboembolic diseases (specifically blood clots, stroke, embolism, and heart attacks)
- bipolar disorder
- colon cancer
- acute leukemia
- chronic pain and fatigue
- nerve pain
- recurrent miscarriages in women of child-bearing age
- pregnancies with neural tube defects, like spina bifida and anencephaly (learn more about having a successful pregnancy with MTHFR)
The risk is possibly increased if a person has two gene variants or is homozygous for the MTHFR mutation.
Various health organizations — including the American College of Obstetricians and Gynecologists, College of American Pathologists, American College of Medical Genetics, and American Heart Association — don’t recommend testing for variants unless a person also has very high homocysteine levels or other health indications.
Still, you might be curious to discover your individual MTHFR status. Consider visiting your doctor and discussing the pros and cons of having blood work run through a lab.
Keep in mind that genetic testing may or may not be covered by your insurance. It’s a good idea to call your carrier ahead of time to ask about costs.
Some at-home genetic testing kits offer screening for MTHFR as well.
- 23andMe is a popular choice that provides genetic ancestry and health information. It’s also relatively inexpensive ($200). To perform this test, you deposit saliva into a tube and send it via mail to a lab. Results take six to eight weeks.
- My Home MTHFR ($150) is another option that specifically focuses on the mutation. The test is performed by collecting DNA from the inside of your cheek with swabs. After shipping the specimen, results take one to two weeks.
Having an MTHFR variant doesn’t mean you need medical treatment, it could just mean you need to take a supplemental vitamin B. Treatment may be indicated when a person has very high homocysteine levels, almost always above the level attributed to most MTHFR variants. Doctors should rule out other possible causes of increased homocysteine, which can occur with or without MTHFR variants.
Other causes of high homocysteine include:
- conditions like diabetes, high cholesterol, and high blood pressure
- obesity and inactivity
- certain medications, such as atorvastatin, fenofibrate, methotrexate, and nicotinic acid
From there, the treatment will depend on the cause and doesn’t necessarily take into account MTHFR. The exception is when you have all of the following together:
- high homocysteine levels
- a confirmed MTHFR mutation
- vitamin deficiencies in folate, choline, or vitamins B-12, B-6, or riboflavin
In these cases, doctors may suggest supplementation to address deficiencies along with medications or treatments to address the specific health condition.
People with MTHFR mutations may also wish to take preventative measures by changing certain lifestyle choices that can elevate homocysteine levels. Things like stopping smoking, getting enough exercise, and eating a healthy, balanced diet may help without the use of medications.
Recurrent miscarriages and neural tube defects are potentially associated with MTHFR. The Genetic and Rare Diseases Information Center says studies suggest that women who have two C677T variants are at an increased risk of having a child with a neural tube defect.
A 2006 study looked at women with a history of recurrent miscarriages. It found that 59 percent of them had multiple homozygous gene mutations, including MTHFR, associated with blood clotting, versus only 10 percent of women in the control category.
Speak with your doctor about testing if you’ve experienced several unexplained miscarriages, have had a child with a neural tube defect, or if you know you have the MTHFR mutation and become pregnant.
Though there is little evidence to support it, some doctors suggest blood clotting medications. Extra folate supplementation may also be recommended.
The MTHFR gene mutation inhibits the way the body processes folic acid and other important B vitamins. Changing up supplementation of this nutrient is a potential focus in countering its effects.
Folic acid is actually a man-made version of folate, a naturally occurring nutrient found in foods. Taking the bioavailable form of folate — methylated folate — may help your body absorb it more readily.
Most people are encouraged to take a multivitamin that contains at least 0.4 milligrams of folate or folic acid each day. Pregnant women are not encouraged to switch prenatal vitamins or care based on their MTHFR status alone. This means taking the standard dose of 0.6 milligrams of folate daily.
Women with a history of neural tube defects should speak with their doctor for specific recommendations.
Multivitamins containing methylated folate include:
Speak with your doctor before changing vitamins and supplements. Some may interfere with other medications or treatments you’re receiving.
Your doctor may also suggest prescription vitamins that contain folate versus folic acid. Depending on your insurance, these options may be more or less expensive than over-the-counter varieties.
Eating foods rich in folate may help naturally support your levels of this important vitamin. Supplementation may still be necessary, however.
Good food choices include:
- proteins like cooked beans, peas, and lentils
- veggies like spinach, asparagus, lettuce, beets, broccoli, corn, Brussels sprouts, and bok choy
- fruits like cantaloupe, honeydew, banana, raspberries, grapefruit, and strawberries
- juices like orange, canned pineapple, grapefruit, tomato, or other vegetable juice
- peanut butter
- sunflower seeds
People with MTHFR mutations may want to avoid foods that contain the synthetic form of folate, folic acid — though the evidence is not clear that is necessary or beneficial. Be sure to check labels, as this vitamin is added to many enriched grains, like pasta, cereals, breads, and commercially produced flours. Learn more about the difference between folate and folic acid.
Your MTHFR status may or may not be impacting your health. More research is needed to assess the true implications, if any, associated with the variants.
Again, many respected health organizations don’t recommend testing for this mutation, especially without other medical indications. Speak with your doctor about the benefits and risks of testing, as well as any other concerns you may have.
Continue to eat well, exercise, and practice other healthy lifestyle habits to support your overall well-being.