More on Folic Acid

Why you need this crucial vitamin now.


The professor couldn't resist taking a survey of his class members. They were all university students pursuing graduate degrees in public health — intelligent and health-conscious, to say the least. First he queried the women: Who needs supplementation with the B vitamin folic acid?

As he recalled the results of the survey, he sounded discouraged. Only 10 percent of the female students were aware that all women of childbearing age who are capable of becoming pregnant should pay attention to their intake of folic acid. (In fact, the professor, who requested anonymity, sounded so frustrated that asking him how the men did seemed cruel.)

It has been nearly six years since the U.S. Public Health Service began recommending that all women who are capable of becoming pregnant — regardless of whether they are trying — consume 400 micrograms of folic acid every day to reduce their risk of having a baby with spina bifida or other neural-tube defects involving incomplete closure of the spinal column. They should take folic acid daily for at least one month, and preferably three months, before becoming pregnant and at least three months into their pregnancy. (Women with a history of neural-tube defects are advised by the Centers for Disease Control and Prevention in Atlanta to take 10 times the recommended dose — 4 milligrams of folic acid daily.) Because it is difficult to get 400 micrograms from diet alone, supplementation is recommended. Yet the message, as crucial as it is, is by no means common knowledge.

A survey released in 1997 by the March of Dimes found that 66 percent of the 2,001 women surveyed realized the value of folic acid in fetal development. That's up from 52 percent in the 1995 survey. But only 23 percent of the women surveyed who were pregnant in the two years before the 1997 survey took a daily vitamin containing folic acid.

What Can You Do? While awareness is improving, public- health experts are understandably frustrated. Because the brain and spinal cord develop very early in pregnancy, it's optimal to begin taking folic acid long before pregnancy is even suspected so the vitamin can exert its maximum protective effect on the fetus. Doing so could cut in half the number of babies born each year in the United States with spina bifida and anencephaly (a condition in which the brain fails to form), the two major types of neural-tube defects, according to the CDC.

Taking folic acid early in pregnancy is important because the neural tube closes 24 to 28 days after conception, according to James L. Mills, M.D., chief of the pediatric epidemiology section of the National Institutes of Child Health and Human Development at the National Institutes of Health, and a renowned expert in the field. "By the time most women discover they are pregnant, the neural tube is probably closed," he says.

So what can you do if you haven't taken your folic acid and are well into your pregnancy? First of all, it's never too late to start making sure to get enough of this important vitamin for you and your baby. "There may be additional benefits to taking folate through pregnancy," says Margaret Thomson, R.N., genetic disease program specialist in the Genetic Disease Branch of the California Department of Health Services. "Pregnant women who maintain high blood levels of folate were less likely to have preterm or low birth-weight babies, according to a recent study published in the American Journal of Clinical Nutrition."

Since the benefits of early supplementation have been established so clearly, statistics may or may not ease your anxiety. "The risk of neural-tube defects in the U.S. is one in 1,000," Mills says.

If you or your doctor is concerned, you may wish to consider prenatal testing. The maternal alpha-fetoprotein (AFP) test is a simple blood test typically done at 16 to 18 weeks of pregnancy. It measures alpha-fetoprotein, a substance produced by the fetus and secreted into the amniotic fluid, eventually entering the mother's blood. Abnormally high amounts of AFP can indicate a neural-tube defect — but not always. It is an imperfect test. If a woman has an elevated AFP, her doctor will usually retest and then do an ultrasound. If no explanation is found, an amniocentesis may be performed.

Why Aren't We Doing It? So what gives? What's so difficult about taking a pill and eating your fruits and veggies? It's the hassle factor, according to Mills. You have to go out and buy the pills, he notes, and then, of course, remember to take

Jo Ann Hattner, R.D., a spokesperson for the American Dietetic Association and clinical nutritionist at Stanford University Medical Center in Palo Alto, Calif., seems to agree. "We're bombarded with messages [about health]," she says, "and all too often, folic acid slips through the cracks." So Hattner tries to convince women that the recommendation can be achieved with little hassle.

Eat the Right Things "It's easy [to take in folic acid] if you remember to focus on citrus foods, dark green leafy vegetables and whole-grain cereals," Hattner says. A half-cup of boiled spinach has 130 micrograms of folic acid; a medium orange 45. "Women need to plan ahead, think about it a little more," she adds. Cut down on processed foods, she advises, and visit the produce department.

By January 1998, under Food and Drug Administration regulations issued in 1996, folic acid was to be added to enriched cereal and grain products, such as flour, corn meal, pasta and rice. And breakfast cereals can be fortified with up to 400 micrograms per serving.

Following the folic acid recommendation may be even more important for some women than others. A 1997 study published in the journal Lancet by Mills of the NIH and his colleagues showed that some women are predisposed to having lower levels of folic acid in their red blood cells than most women, although the experts don't understand why. About 5 percent to 15 percent of women could be affected, Mills estimates.

Although there is a test that can measure blood levels of folic acid, Mills doesn't recommend routine testing because women should take the same action regardless of their test results. "Just make sure to get the recommended amounts," he says.

The Future Many public-health experts say awareness is growing, albeit slowly. "It is moving in the right direction, but we are not there yet," says Godfrey Oakley, M.D., director of the division of birth defects and developmental disabilities for the CDC. The foods chosen for fortification — breads and cereals — are eaten by most people, so the hope is that all women will soon be getting plenty of folic acid during their childbearing years.

Meanwhile, Oakley and his wife have hatched a plan they hope will catch on: "Every time you get invited to a wedding," he suggests, "take a year's supply of folic acid and give it to the bride."