The Food and Drug Administration approved folic acid fortification of corn masa flour on April 14, 2016. The approval allows manufacturers to voluntarily add up to 0.7 mg folic acid per pound of corn masa flour, consistent with the levels of certain other fortified cereal grains. Since 1998, FDA has mandated folic acid fortification of enriched grains.
Folic acid, a synthetic form of folate, is a B vitamin that when taken by a pregnant woman may help prevent neural tube defects, which are birth defects affecting the brain, spine and spinal cord. After mandating fortification of grains labeled as enriched — the most common type of flour used by bakers — more than 25 years ago, the number of babies born in the US with neural tube birth defects declined by about 36%.