Why you need folic acid
If you're pregnant or might become pregnant, it's critically important to get enough folic acid, the synthetic form of vitamin B9, also known as folate.
Folic acid helps prevent neural tube defects (NTDs) – serious birth defects of the spinal cord (such as spina bifida) and the brain (such as anencephaly). The neural tube is the part of the embryo from which your baby's spine and brain develop. NTDs affect about 3,000 pregnancies a year in the United States.
Neural tube defects occur at a very early stage of development, before many women even know they're pregnant – which is why it's important to begin taking folic acid before you start trying to conceive.
The Centers for Disease Control and Prevention (CDC) reports that women who take the recommended daily dose of folic acid starting at least one month before conception and during the first trimester of pregnancy reduce their baby's risk of neural tube defects by up to 70 percent.
Some research suggests that folic acid may help lower your baby's risk of other defects as well, such as cleft lip, cleft palate, and certain types of heart defects. It may also reduce your risk of preeclampsia, a serious blood pressure disorder that affects about 5 percent of pregnant women.
What else does folic acid do for you? Your body needs this nutrient to make normal red blood cells and prevent a type of anemia. It's also essential for the production, repair, and functioning of DNA, our genetic map and a basic building block of cells. Getting enough folic acid is particularly important for the rapid cell growth of the placenta and your developing baby.
How much folic acid you need
To reduce your baby's risk of developing a neural tube defect, experts recommend that you take 400 micrograms (mcg) of folic acid a day, beginning at least a month before you start trying to get pregnant.
In fact, because half of the pregnancies in the United States are unplanned, the CDC, the U.S. Public Health Service, the March of Dimes, the American College of Obstetricians and Gynecologists (ACOG), and other experts strongly recommend that all women of childbearing age get 400 mcg of folic acid every day.
Some groups, such as the U.S. National Institutes of Health, suggest boosting your intake to at least 600 mcg daily once you're pregnant.
Check the label of your multivitamin supplement to be sure you're getting enough. If you're not, you can switch brands or take folic acid separately. (Never take more than one multivitamin a day.)
If you're taking prescription prenatal vitamins, they probably contain 800 to 1,000 mcg of folic acid. Again, check the label.
Don't take more than 1,000 mcg per day of folic acid unless your healthcare provider advises you to. This is particularly important if you are a vegan. Vegans are at risk of being deficient in vitamin B12 and taking too much folic acid would make it hard to diagnose that deficiency.
When you might need extra folic acid
Women who are obese appear to be more likely to have a baby with a neural tube defect. If you're significantly overweight, see your healthcare provider before you try to conceive. She may advise you to take more than 400 mcg of folic acid a day.
If you've previously been pregnant with a baby with a neural tube defect, you'll probably be advised to take 4,000 mcg of folic acid a day. Be sure your current providers are aware of your history and schedule a visit before you try to get pregnant. With no intervention, women in this situation have a 3 to 5 percent chance of having another pregnancy complicated by an NTD.
Some people have a genetic variation – known as a methylenetetrahydrofolate reductase (MTHFR) mutation – that makes it more difficult to process folate and folic acid. If you know you have this mutation, talk with your doctor to make sure you're getting enough folic acid.
Women who are diabetic or are taking certain antiseizure medications are also more likely to have a baby with an NTD. If either of these situations applies to you, see your provider at least a month before trying to conceive to find out how much folic acid you should be taking and to monitor your condition in general.
Food sources of folic acid
Food manufacturers are required by the U.S. Food and Drug Administration to add folic acid to enriched grain products, such as breakfast cereals, bread, pasta, and rice. Some fortified breakfast cereals contain 100 percent of the recommended daily amount.
This is meant to be helpful for women who don't take a supplement and aren't planning to get pregnant, but most women don't eat these foods consistently enough to rely on them as a source of folic acid.
Even if you eat a complete serving of a fully fortified cereal every day, you can't be sure you're getting what you need. (For one thing, synthetic nutrients added to cereals tend to end up in the milk at the bottom of the bowl.)
Foods that are naturally rich in folate are not a good source either. Oddly enough, research shows that the body absorbs folic acid from supplements much better than the folate that occurs naturally in certain foods. What's more, folate can be lost from foods during storage or destroyed by cooking.
So if you eat foods rich in folate, consider them a complement to your supplement. Good sources include:
- dried beans, peas, and nuts
- dark green vegetables such as broccoli, spinach, collard or turnip greens, okra, Brussels sprouts, and asparagus
- citrus fruit and juice
Is a supplement recommended?
Yes. As mentioned above, many authorities, including ACOG and the March of Dimes, recommend that all women of childbearing age take a multivitamin with folic acid or a folic acid supplement every single day.
Signs of a folic acid deficiency
The signs of folic acid deficiency can be subtle. You may have diarrhea, anemia, loss of appetite, and weight loss, as well as weakness, a sore tongue, headaches, heart palpitations, and irritability.
If you're only mildly deficient, you may not notice any symptoms at all, but you won't be getting the optimal amount for your baby's early embryonic development.