Folic acid

What is folic acid?

Folic acid is a B vitamin that the cells of your body need for healthy growth and development. If you take it before pregnancy and during early pregnancy, it can help protect your baby from serious birth defects of the brain, spine and spinal cord called neural tube defects (NTDs). The neural tube is the part of a developing baby that becomes the brain and spinal cord.

A common type of NTDs is spina bifida. With spina bifida, the spinal cord or the bones in the spine do not form correctly, leaving a gap or opening. NTDs happen in the first month of pregnancy, before you may know that you’re pregnant. This is why it’s important to have enough folic acid in your body before you get pregnant.

NTDs affect about 3,000 pregnancies each year in the United States. It’s recommended that all women take at least 400 micrograms (mcg) of folic acid every day before getting pregnant and during early pregnancy.  

Some studies show that folic acid also may help prevent birth defects in a baby’s mouth called cleft lip and palate. A cleft lip is a birth defect in which a baby’s upper lip doesn’t form completely and has an opening in it. A cleft palate is a birth defect in which a baby's palate (roof of the mouth) doesn’t form completely and has an opening in it.

How can you get enough folic acid?

There are several ways to get enough folic acid:

• Taking a vitamin supplement that has folic acid in it.
• Eating foods fortified with folic acid. Fortified (also called enriched) means a food has certain nutrients added to it.
• Getting a combination of the two: taking a vitamin supplement that has folic acid in it and eating foods fortified with folic acid.

How much folic acid do you need?

Here’s what you need to know about taking folic acid to help prevent NTDs in your baby:

Most women

Take a vitamin supplement with at least 400 mcg of folic acid every day before you get pregnant, even if you’re not planning a pregnancy. It’s recommended you start at least 1 month before pregnancy through the first 12 weeks of pregnancy. Your vitamin supplement can be:

• A multivitamin. This is a pill that contains many vitamins and other nutrients that help your body stay healthy.
• A prenatal vitamin. Your healthcare provider may give you a prescription for prenatal vitamins, or you can get them over the counter without a prescription.
• A supplement that contains just folic acid

Women at high risk for NTDs

If you’re at high risk for having a baby with an NTD, you may need a higher dose of folic acid each day to help prevent an NTD. You’re at high risk if:

• You’ve had a pregnancy affected by an NTD in the past
• You or your partner has an NTD.
• Your partner has a child with an NTD.

Other risk factors for having a baby with an NTD include taking certain medications for a seizure disorder, having diabetes or being obese. If you have any of these risk factors, talk to your provider about whether you need extra folic acid each day.

Ask your provider how to safely get the amount of folic acid you need. It’s not safe to take several multivitamins or prenatal vitamins because you can get too much of other nutrients, which may be harmful to your health. Your provider can help you figure out the best and safest way for you to get the right amount of folic acid.

How can you get folic acid from food?

You can get folic acid from some foods. Check the product label to see how much folic acid you get in each serving. Look for the word “fortified” or “enriched” on labels on foods like: 

• Breads and cereals
• Pasta and rice
• Products made from a kind of flour called corn masa, like tortillas, tortilla chips, taco shells, tamales and pupusas

Some foods have folate which is a naturally occurring form of folic acid. It’s hard to get all the folic acid you need from food. Even if you eat foods that have folic acid in them, take your vitamin supplement each day, too. Foods that are good sources of folate are:

• Beans and peas (called legumes), like kidney beans, lentils, and black-eyed peas
• Dark green leafy vegetables, like spinach and mustard greens
• Asparagus
• Broccoli
• Brussel sprouts
• Nuts, like walnuts (but don’t eat them if you have a nut allergy)
• Citrus fruits and fruit juices, especially oranges and orange juice
• Beef liver

How do you read a product label to see how much folic acid is in a vitamin supplement?

To find out if a vitamin supplement has folic acid in it, check the label (also called supplement facts). The label is usually on the back of the bottle. Look for the word “folate” on the label to see how much folic acid you’re getting. The label tells you this information:

• Serving Size. This tells you how much of the product is in one serving. For example, one multivitamin is often one serving.
• Servings Per Container. This tells you how many servings are in the whole bottle. For example, if two pills are one serving and the bottle has 30 multivitamins in it, that’s 15 servings.
• Nutrients, like vitamin D, folate and calcium, in each serving.
• % Daily Value (also called DV). This is the amount of a nutrient in a serving.

Labels for foods that contain folate usually list mcg DFE of folate and mcg of folic acid, just like for vitamin supplements.

If you have an MTHFR variant, can taking folic acid help prevent NTDs in your baby?

Yes. If you have an MTHFR variant, taking 400 mcg of folic acid every day before and during early pregnancy can help prevent NTDS in your baby.

MTHFR stands for methylenetetrahydrofolate reductase. It’s an enzyme (protein) that helps your body break down and use folate. You have two copies of the MTHFR gene, one from each parent. Genes are parts of your body’s cells that store instructions for the way your body grows and works. Genes are passed from parents to children. A variant is a change in a gene’s instructions.

If you have an MTHFR variant, your body may not process folate as well as it should. If you know you have an MTHFR variant or you think it runs in your family, talk to your provider. Having an MTHFR variant may increase the levels of a substance in your blood called homocysteine. Some studies have shown that too much homocysteine in your blood may increase the risk for blood clots, heart conditions and stroke. You can find out your homocysteine levels with a blood test. If your level is high, your provider may order a genetic test to see if you have an MTHFR variant.

If you have an MTHFR variant, talk to your provider for information on the right amount of folic acid to take.

Folic Acid Health Action Sheet

More information

Folic Acid to Prevent Neural Tube Defects

Show Your Love Preconception Health

Last reviewed: October 2025