(HealthDay)—Makers of corn masa flour can voluntarily add up to 0.7 mg. of folic acid per pound of corn masa flour under a new approval by the U.S. Food and Drug Administration.

Folic acid is a B vitamin that, when taken by , can help prevent neural tube birth defects such as , the agency said Thursday in a news release.

Neural tube defects affect the brain, spine and spinal cord. Pregnant women who don't get enough of the B vitamin have a greater-than-average chance of having babies born with . In 2012, the March of Dimes Foundation, the American Academy of Pediatrics and others petitioned the FDA to extend voluntary fortification of corn masa flour.

Corn masa is a staple for many Latinos, as it's used in foods including tortillas, tamales, taco shells and corn chips. U.S. government rules also allow to be added to breakfast cereals, infant formula and medical foods, and the vitamin must be added to grain-enriched products such as breads, rolls, noodles and pasta, the FDA said.

The agency said it can approve additions to food only after formally reviewing each additive's safety.

Consumers should check food ingredient labels to find products fortified with folic acid, the FDA said.

More information: This video from the March of Dimes describes how folic acid helps prevent neural tube birth defects.