Folic Acid and Autism: Should We Supplement?

A recent study out of Norway found that women who take folic acid early in their pregnancy or before they become pregnant reduce their offspring’s risk for autism. What does that mean for women trying to conceive?

Folic Acid’s Role during Pregnancy

Folic acid is important in the prevention of neural tube defects. Since neural tube closure occurs early in pregnancy (sometimes before a woman knows she is pregnant), folic acid is recommended for women of childbearing age as well as pregnant women. Prenatal multivitamin supplements contain folic acid, typically somewhere between 800 and 1,000 mcg. The recommended dietary allowance for pregnant women is 600 mcg.

Regular multivitamins for adults usually contain 400 mcg of folic acid, in line with the recommended dietary allowance.

Folic Acid in Our Food Supply: Fortification

Supplements are not the only source of folic acid. Many grain products, including flour, pasta, and breakfast cereals, are fortified with folic acid. The reason for the fortification of grain products is that food sources contain levels of naturally occurring folate much lower than the recommended dietary intake. Folic acid from fortified food (and folic acid supplements) has higher bioavailability than the naturally occurring folate obtained from foods.

Folic acid fortification of flour, pasta, and breakfast cereals in the United States and Canada is estimated to supply 100 mcg to 200 mcg of folic acid daily. However, this can vary quite widely depending on individual food choices.

Here are some food sources of folic acid from both naturally occurring and fortified sources.

Food	Folic Acid (mcg DFE)
Kellogg’s Special K, 1 cup	676
General Mills Total Raisin Bran, 1 cup	673
General Mills Cheerios, 1 cup	336
Lentils, cooked, 1/2 cup	179
Chickpeas, cooked, 1/2 cup	141
Spaghetti, enriched, cooked, 1/2 cup	83
Black beans, cooked, 1/2 cup	80
Avocado, 1/2 fruit	60

The Bottom Line

So, should you supplement with extra folic acid in addition to your prenatal supplement? Well, look into how much folic acid you may already be getting from fortified foods as well as naturally occurring sources. If you are pregnant and already taking a prenatal multivitamin, you likely do not need further supplementation. Consult with your physician before taking an extra folic acid supplement.