Folic acid is the human-made version of folate, a B vitamin that plays several roles in the body. During pregnancy, one of its most important functions is preventing a group of birth abnormalities called neural tube defects.

The neural tube is a structure in the human fetus that develops into the brain and spinal cord.

Neural tube defects happen when the neural tube does not close early in development. This dysfunction can cause severe disability, and it can even be fatal.

This article explains the benefits of taking folic acid for pregnancy, when to take it, and how much to take.

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Folic acid is a synthetic (human-made) form of folate. Folate is a type of B vitamin.

Everyone needs folate, but it is especially important during pregnancy because of its role in preventing birth abnormalities.

The Food and Nutrition Board recommend that adults get 400 micrograms (mcg) of folic acid per day, which should increase to 600 mcg during pregnancy and then reduce slightly to 500 mcg when breastfeeding.

Folic acid is the manufactured form of folate, an important B vitamin that occurs naturally.

Learn more about folic acid and folate here.

A person can get folic acid in their diet by taking supplements and eating foods fortified with folic acid, such as some breakfast cereals. A person can check the nutrition label to see whether a food is fortified with folic acid.

Many foods — including spinach, avocado, and banana — contain folate, the naturally occurring form of this vitamin.

The MTHFR gene myth

In the alternative health community, a popular myth suggests that people with certain variants in the MTHFR gene cannot process folic acid. However, research has shown that this is not true.

Proponents of this myth claim that pregnant people need a different form of folic acid or even that folic acid is harmful. They may use this myth to sell supplements or promote alternative health scams.

According to the Centers for Disease Control and Prevention (CDC), MTHFR gene variants are common. MTHFR mutations are not an illness, and people with mutations in this gene do not require an alternative form of folic acid.

People with this genetic difference can metabolize all forms of folate, including folic acid.

Moreover, folic acid is the only type of folate directly linked to the prevention of neural tube defects. Therefore, people should take folic acid regardless of which type of MTHFR gene they carry.

Folic acid helps the body make new cells, including red blood cells.

People who do not get enough folic acid may develop a condition called folate-deficiency anemia.

In people with this condition, the body cannot make enough red blood cells to carry oxygen throughout the body. This impairment can affect many aspects of health, including organ function.

During pregnancy, a person needs more folic acid than usual because folic acid also helps the fetus grow and develop. One of its most important roles is preventing neural tube defects, including spina bifida and anencephaly.

Spina bifida is a condition in which the bones of the spinal cord do not fully close. It can cause a range of disabilities that may affect development, mobility, and overall health.

A baby with anencephaly either does not develop a brain, or the brain is very underdeveloped. In almost all cases, anencephaly will be fatal — either in the womb or very shortly after birth.

Some research also suggests that folic acid may reduce the risk of pregnancy complications such as preterm labor, problems with the development of the placenta, and other birth abnormalities, such as cleft palate and heart disease.

Anyone who wishes to become pregnant should start taking folic acid supplements before they start trying.

The reason for this is that neural tube defects occur early in development, often before a person knows that they are pregnant.

As about half of pregnancies are unplanned, experts recommend that anyone who can get pregnant take folic acid supplements. Doing so ensures that even if a pregnancy is a surprise, the likelihood of neural tube defects is low.

Folic acid is water soluble, which enables the body to metabolize it quickly. For this reason, those taking folic acid supplements need to take one every day.

There is no need to take the supplement at a specific time of day or with a meal. However, developing a habit, such as taking a prenatal vitamin every morning with breakfast, may make it easier to remember to take folic acid.

The CDC note that in most cases, each folic acid pill or multivitamin contains 400 mcg of folic acid. A person can check the supplement label to confirm this.

The American College of Obstetricians and Gynecologists (ACOG) recommend taking a daily supplement containing 400 mcg of folic acid, regardless of how much folate a person gets in their diet.

A person should not take more than 1,000 mcg of folic acid per day unless their doctor recommends otherwise. Too much folic acid may conceal symptoms of a vitamin B12 deficiency.

Foods that are naturally high in folate, the natural form of folic acid, include:

  • Banana: 24 mcg per medium fruit
  • Spinach: 131 mcg per one-half cup boiled
  • Black-eyed peas: 105 mcg per one-half cup boiled
  • Avocado: 59 mcg per one-half cup
  • Broccoli: 52 mcg per one-half cup
  • Orange juice: 35 mcg per three-quarters cup
  • Asparagus: 89 mcg per four spears
  • Brussels sprouts: 78 mcg per one-half cup

Fortified cereals, such as breakfast cereal and oatmeal, are also high in folic acid. A person can check the label to learn the exact quantity.

It is possible to get enough folic acid from the diet, but the ACOG still recommend taking a supplement while pregnant.

It is safe to combine folic acid supplements with naturally occurring folate in the diet.

It is not possible to get too much folate from food. However, it is possible to get too much folic acid from supplements, including fortified cereals.

A person does not need to monitor their daily intake of folate from food but should monitor their use of supplements containing folic acid.

Prenatal vitamins and many multivitamins contain folic acid. People who take multiple supplements should review each label to make sure that they are not taking more than 1,000 mcg of folic acid per day.

A 2020 study of mice found that both too much and too little folic acid in the diet harmed the brain development of mouse offspring before they were born.

Scientists need to do more research to investigate whether this is also the case in humans.

Folic acid may improve the chances of getting and staying pregnant.

A 2016 study involving nearly 4,000 women compared those who took folic acid with those who did not.

The participants who used the supplement were more likely to get pregnant. Among those whose cycles were irregular or very short or long, there was an even closer correlation between folic acid and getting pregnant.

Additionally, folic acid may help prevent pregnancy loss because some birth abnormalities, including neural tube defects, may lead to this complication.

Folic acid is an important nutrient for everyone, but it is especially key during pregnancy.

People who are looking to become pregnant may wish to talk to a healthcare provider about the right dosage of folic acid. Those who are already pregnant can take a folic acid test to determine how much folic acid is in their blood. The result can indicate the chance of having a baby with neural tube defects.