Health

Folic Acid Deficiency Plummets

May 12, 1999 / 5:18 PM EDT / AP

Folic acid deficiency has nearly disappeared in the United States since the government ordered food manufacturers to add the vitamin to flour, rice and other grain products, a study concludes.

Folic acid is found naturally in green leafy vegetables and some other foods. If women eat too little of it when they become pregnant, they risk having babies with spina bifida and other neural tube defects.

To help protect against these birth defects, the Food and Drug Administration ordered manufacturers to begin fortifying foods with folic acid in January 1998.

The latest study is the first major effort to see what effect this has had. The researchers studied a group of mostly white, middle-aged residents of one Massachusetts town and looked at their blood levels of folic acid before and after the food fortification began.

They found that average blood levels of folic acid doubled. Just under 2 percent still had folic acid deficiency, compared with 22 percent before the vitamin was added to food.

"What this shows is that there's really been quite a dramatic impact in this middle-aged population," said a co-author of the study, Dr. Irwin H. Rosenberg of the U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University in Boston.

The study was based on 1,106 volunteers in the Framingham Heart Study, which has followed the cardiovascular health of residents of a Boston suburb for 50 years.

The study hints that the extra folic acid could do more than reduce birth defects. Folic acid lowers levels of homocysteine, an amino acid that results naturally from the breakdown of protein. The study found average homocysteine levels fell about 7 percent.

Some studies have found that people with high homocysteine levels have an elevated risk of heart trouble. However, there is no evidence that bringing down homocysteine will keep the heart healthy.

Still, Rosenberg said the latest findings could be good news for the heart if lowering homocysteine does turn out to be beneficial.

The prevalence of unusually high homocysteine levels fell from 19 percent to 10 percent of the volunteers. Rosenberg said this large a drop could "have a substantial effect on the calculated risk of heart disease and stroke."

The March of Dimes and some other health organizations had urged the FDA to require higher levels of folic acid in food. Dr. Donald Mattison, the group's medical director, said the latest study "suggests to us that we should see some health benefits" from the additive.

Rosenberg said he believes the data means that folic acid levels have increased substantially for everyone, not just middle-aged whites, but Mattison said this remains to be proved.