Study: Women Need Extra Folic Acid

B O S T O N, June 19 -- Certain birth defects have decreased by almost 20 percent since the government in 1998 required enriched grain foods to be fortified with the nutrient folic acid, a new study says.

But women of childbearing age should still take extra amounts of the vitamin.

Folic acid, also known as folate, is a type of vitamin B found in green leafy vegetables, citrus fruits, dried beans and liver. Folic acid is an essential vitamin the body needs for proper functioning, particularly during the first few weeks of life.

Scientists have known since the 1950s that low levels of folic acid during pregnancy can cause dangerous neural tube defects in newborns, though it is not yet known how the vitamin works.

What Are Neural Tube Defects?

The most common types of neural tube defects are spina bifida and anencephaly, which occur when the spinal column fails to close in the growing fetus. Anencephalic fetuses usually do not develop a functional brain or spinal cord and are often stillborn. Spina bifida infants can live to adulthood, with varying degrees of cognitive and physical disabilities, ranging from mild curvature of the spine to severe paralysis and mental retardation.

Although the fortification has lowered the rates, neural tube defects still occur in approximately 1 in 1000 births, with about 2,500 affected children born in the United States every year.

The new study by the Centers for Disease Control in the latest issue of The Journal of the American Medical Association reveals that while the folic acid fortification program has been successful overall, babies are still being born with defects because pregnant women may still not be getting enough of the vitamin in their diets.

Enriched foods are designed to give an average eater about 100 micrograms of folic acid per day. But experts say women need at least 400 micrograms to protect their babies from neural tube defects.

Prenatal screening may also be playing a role in overestimating the fortification program's success. "Many neural tube defects are screened out early in pregnancy, since once detected, many women choose to terminate their pregnancies," says Dr. Hope Ricciotti, a women's nutrition specialist at Beth Israel Deaconess Medical Center in Boston.