Folic acid may help prevent Down Syndrome

A new study suggests women who don't metabolize folic acid properly have a greater risk of having a Down syndrome child

September 29, 1999
Web posted at: 5:31 p.m. EDT (2131 GMT)

(CNN) -- Women with a genetic mutation which interferes with the body's ability to absorb folic acid are at higher risk for having children with Down syndrome, according to a study sponsored by the Food and Drug Administration (FDA). The results have researchers wondering if folic acid supplements can help reduce the risk of Down syndrome, as they reduce the risk of spina bifida.

The government study, published in the American Journal of Clinical Nutrition, found mothers who had trouble metabolizing folic acid were 2.6 times more likely to have a child with Down syndrome.

But FDA Commissioner Dr. Jane Henney said this research has provided only one clue to solving the mystery of Down syndrome. She pointed out that millions of women appear to have this genetic abnormality, but only a very small percentage have a child with Down syndrome. So it is not the genetic mutation alone which triggers the condition.

"There seems to be both a genetic issue here and nutritional issue here. And if the diet is high in folic acid then the opportunity for Down syndrome or the risk of Down syndrome appears to be less," Henney said.

Researchers studied 107 women whose average age was 30. Of those, 57 had given birth to a child with Down syndrome.

The FDA researchers did not give women any folic acid supplements, so they cannot predict if supplements would help reduce risk or in what doses they might help. They say treatment studies are needed to make these determinations.

If folic acid does prove helpful, women would need to take it well before they conceive.

"Folic acid is very important co-factor in how DNA works, how cells function. So there are many potential mechanisms for folate to work," said Dr. Kenneth Rosenbaum of Children's Hospital.

Folic acid, which is a B vitamin found in leafy green vegetables, beans, tuna, eggs and other foods, is already proven to help prevent neural tube defects such as spina bifida.

In 1996, the FDA recommended certain grain products including some cereals be fortified with folic acid. This latest study is being touted as further evidence its recommendations were well founded.

"This finding just adds support not only to the fortification plan , but that it might be helpful in other ways. And we will have to keep monitoring to see if that was the right amount of fortification," Henney said.

Down syndrome is a genetic disorder that combines metal retardation with physical abnormalities such as a broad, flat face and slanting eyes. Those with Down syndrome are at high risk of heart defects, visual or hearing problems and other health-related difficulties.

There are 250,000 Americans with the condition, according to March of Dimes estimates.

Medical Correspondent Eileen O'Connor and The Associated Press contributed to this report.