This powerful little B vitamin can prevent some devastating birth defects.
You may have already heard that when you’re trying to get pregnant, folic acid is a must-have vitamin. Why? “It’s needed for DNA and making cells—it’s very important for cell development and growth in pregnancy,” says Heather Hamner, M.P.H., a nutrition epidemiologist at the Centers for Disease Control and Prevention’s (CDC) National Center on Birth Defects and Developmental Disabilities (NCBDDD) in Atlanta. Not getting enough of this important B vitamin (sometimes known as B9) can be devastating for a baby, increasing the risk of neural tube defects (NTDs) such as spina bifida, in which the spinal cord fails to close, and anencephaly, in which the brain doesn’t develop as it should.
But when women get adequate amounts of folic acid prior to (ideally, at least three months before) and very early in pregnancy, their risk of having a baby with an NTD plummets 50 to 70 percent. Crucial development of the spine and brain happens so early in gestation that if a woman waits to take the vitamin until she knows she’s pregnant, it might be too late. Says Judy Meehan, executive director of the National Healthy Mothers, Healthy Babies Coalition in Alexandria, Virginia, “Brain development is in the very first weeks after conception, so by the time you find out you’re pregnant, you [may have] missed a good opportunity for prevention.”
So how much should you get? The current recommendation by the Institute of Medicine (IOM), which sets the recommended dietary allowance (RDA) for nutrients, is that all non-pregnant women of childbearing age get 400 micrograms of folic acid every day—meaning a daily pill of either folic acid on its own or in a multivitamin (nearly all multivitamins contain the RDA for folic acid). But that’s just part of the picture: The IOM also wants women to strive for adequate dietary folate—that’s the form of the vitamin that’s found naturally in foods like orange juice and other citrus juices, whole grains, green leafy vegetables, and many beans and legumes. But because it’s very hard to get enough folate from diet alone—even a top source like orange juice has just 74 mcg in a 1-cup serving—most of us need a daily supplement as well.
More Is More
The government recommendations may set good goals, but not enough people are reaching them, according to Godfrey P. Oakley, Jr., M.D., M.S.P.M., a research professor at the Rollins School of Public Health at Emory University in Atlanta. “About 25 percent of women are getting the 400 micrograms a day—so most women still aren’t getting enough.”
Another frightening figure is the CDC’s finding that between 1999 and 2004, levels of folic acid in American women’s blood declined 8 to 16 percent. This dip occurred despite the fact that we get a boost from the 1998 government-mandated fortification with folic acid of many breads, cereals, and grains. Hispanic women are at particular risk, according to Oakley, since they’re more likely to eat unfortified foods, such as cornmeal. Hispanic babies are one-and-a-half to two-times more likely to be born with an NTD, reports the Spina Bifida Association. Still, in the 10 years since folic acid has been added to enriched grain products, there’s been an approximate 30-percent drop in NTDs.
Since it can be tough to get people to change their behavior—namely, take a pill every single day—some public-health experts, including Oakley, would like to see even more folic acid added to the foods we eat. Safety isn’t a big concern, since folic acid is a water-soluble vitamin, meaning that anything the body can’t use is excreted as urine. That’s also why the vitamin must be taken daily. Overdosing and side effects from too-high dosages are virtually unheard of, says Oakley. The IOM has set an upper limit of 1,000 mcg daily, though women who’ve had a previous NTD pregnancy should talk to their doctor about how much is recommended for them, as it’s likely to be much higher. Obese women and women with diabetes or epilepsy are also at increased risk of an NTD pregnancy and may need to take larger amounts of folic acid. (Women who are considered at average risk, once they are pregnant, should get 600 mcg of folic acid daily.)
