Fortifying the U.S. food supply with folic acid was not associated with a decline in certain birth defects that researchers expected to see in California, a finding likely to contribute to an ongoing debate about the future of the fortification program.
The study of more than 1.3 million California births and pregnancies spanning two decades is published in Birth Defects Research Part A. The research examines neural tube defects, which affect a baby's brain and spine, and which were the intended target of fortification with folic acid, a B vitamin. However, neural tube defects were already becoming less common before fortification began, and their decline slowed substantially after fortification was introduced, the study found.