Folic acid more vital for fetus than we realized?

Perhaps you heard recently of a study linking folic acid supplementation and a reduction in the risk of autism.

While this is just a preliminary study, if future research confirms the link, it will add a new and powerful reason for women of childbearing age to consider the health benefits of this B vitamin for their prospective children.

Our knowledge about folic acid dates to the early 20th century, when scientists identified deficiency of the vitamin as a cause of anemia. In subsequent decades, more became known about the role of folic acid in the body. By the early 1960s, a link between folic acid deficiency and common birth defects such as spina bifida was discovered. Subsequent research confirmed the link and led to a decision by the federal government to fortify cereals with folic acid.

Folic acid is naturally found in leafy vegetables, legumes (such as beans), citrus and whole grains. Today, many processed foods are enriched with folic acid, including breakfast cereals, pasta, breads and white rice.

Despite the widespread availability of folic acid in many foods, many nutritionists say women still do not get enough. Also, the type of folate found in foods is not as easily used by the body as the manmade form.

Studies have shown that more than 70 percent of open neural tube defects can be prevented through the routine supplementation of 400 micrograms of folic acid daily in the diet of women of childbearing age. Open neural tube defects include spina bifida and anencephaly (in which the fetal brain fails to fully form). They are among the most common preventable birth defects.

The benefits of folic acid in preventing birth defects are most pronounced when it is supplemented prior to conception, although some benefits persist in the early stages of pregnancy.

A study published in the Feb. 13 Journal of the American Medical Association established a potential link between folic acid supplementation and the prevention of autism.

The study, performed in Norway, followed more than 85,000 children born between 2002 and 2008. An analysis compared children born to mothers who took folic acid supplements from 8 weeks before to 4 weeks after the start of pregnancy with children born to mothers who did not use a folic acid supplement.

The study looked at rates of diagnosis of autism and related disorders. It found that the rate of autism diagnosis in the children whose mothers had taken folic acid was about 40 percent lower than the rate among children whose mothers did not use the supplement.

It is important to note that the study results did not establish a direct link between folic acid and autism nor did they demonstrate that folic acid supplements prevent autism. Some children whose mothers took folic acid supplements were later diagnosed with autism, but overall the rate was lower.

No doubt, more research will further investigate the possible link between folic acid supplements and autism. For now, all women of childbearing age are advised to take a daily 400 microgram supplement of folic acid to reduce the risk of neural tube defects such as spina bifida, for which the link is well established.

Dr. Matthew A. Clark is a board-certified physician in internal medicine and pediatrics practicing at the Ute Mountain Ute Health Center in Towaoc.