In a recent research, the United States Preventive Services Task Force discovered that folic acid supplements reduce therisk of neural tube defects in babies.
As it advised in 2009, the independent panel of experts said women who are pregnant or able to get pregnant should take a daily supplement that contains between 400 and 800 micrograms of folic acid to prevent these potentially fatal birth defects.
Neural tube defects occur when the brain or spinal cord do not develop properly, leading to serious disabilities or even death. These birth defects take place very early in pregnancy. Sometimes they occur even before a woman knows that she is expecting, the task force explained.
Folic acid supplements are most beneficial if women take them one month before becoming pregnant and continue taking them for the first three months of pregnancy, the panel concluded.
Folic acid is a naturally occurring B vitamin found in many fruits and vegetables, such as leafy greens, broccoli and orange juice. In the United States, many foods are also fortified with folic acid.
Still, many women don't get the recommended amount of folic acid through their diet, according to the recommendations published online Jan. 10 in the Journal of the American Medical Association.
"The task force found convincing evidence that the risk of neural tube defects can be reduced when women take a daily folic acid supplement of 400 to 800 micrograms," said task force member Dr. Alex Kemper.
"These supplements can be taken as a daily multivitamin, prenatal vitamin or single tablet that has the recommended amount of folic acid," Kemper said in a task force news release. He is a professor of pediatrics at Duke University Medical School, in Durham, N.C.
In addition, the introduction of folic acid-fortified foods in Canada was associated with a decrease in babies being born with heart defects, a new study found.
Researchers reviewed data from nearly 6 million births in Canada. The births occurred between 1990 and 2011. Folic acid food fortification became mandatory for all types of flour, enriched pasta and cornmeal in 1998 in Canada.
During the study period, there was an 11 percent decline in rates of congenital heart defects overall. But decreases weren't seen in all types of heart defects present at birth.
The biggest declines -- between 15 percent and 27 percent -- were in structural defects of the heart, such as holes in the wall of the heart or a narrowing of the major artery (the aorta) that carries blood to the body from the heart, the investigators found.
But, there was no reduction in heart defects at birth caused by an abnormality in the number of an infant's chromosomes, the findings showed.
An estimated 650,000 to 1.3 million children and adults in the United States have congenital heart disease, the researchers said. A hole in the wall of one of the heart's ventricles is the most common type of defect in children. These defects account for nearly 620,000 of the cases, the researchers added.
Folic acid deficiency during pregnancy can cause a number of complications. These include anemia and neural tube defects (such as spina bifida, an abnormality of the spine and spinal cord), the researchers explained.
Women who are likely to get pregnant should start taking folic acid supplements before conceiving because they may not get enough folic acid from their diet alone, said study senior author Dr. K.S. Joseph. He's a professor of obstetrics and gynecology at the University of British Columbia in Vancouver.
Joseph added that the study findings likely apply to the U.S. population as well. That's because the United States began fortifying foods with folic acid around the same time as Canada, he said.
Although the study found an association between folic acid food fortification and a decline in certain heart-related birth defects, it did not prove a cause-and-effect relationship.