"One of the great publichealth success stories of the past couple of decades can be found in your cereal bowl. Since  the Food and Drug Administration has required that breakfast cereals breads rice pasta and other grain products made with enriched flour come fortified with folic acid. When consumed by women before and during early pregnancy this B vitamin plays a critical role in preventing severe brain and spinal cord defects. Thanks to mandatory fortification the number of babies born in the U.S. with neural tube defects has dropped by roughly  percent http  or about  babies a year  since the s. The story of folic acid is one of the great public health stories of  ever says Dr. R.J. Berry who works with the Division of Birth Defects and Developmental Disabilities of the Centers for Disease Control and Prevention in Atlanta. But theres one notable exception to this success story  Hispanic women  and researchers think the reason may lie in a staple of their diet tortillas. Under current FDA rules tortillas corn chips and other foods made with corn masa flour cant be fortified with folic acid. So a coalition of groups including the March of Dimes Foundation and the National Council of La Raza has petitioned the FDA to change its stance and allow corn masa flour to be fortified with folic acid. According to the March of Dimes about  pregnancies in the U.S. are affected by neural tube defects each year. The rates are highest among Hispanics Latina women are roughly  percent more likely to have a baby with a neural tube defect compared to nonLatina white women. The exact cause of this discrepancy isnt known. Researchers say http there may be genetic factors that predispose the children of some Hispanic women to neural tube defects. But they suspect diet is also a factor Part of the reason was that these groups just werent consuming the same level of wheat flour products. Instead they were consuming corn masa flour products because that was the staple grain in that diet says Cynthia Pellegrini senior vice president of public policy and government affairs at the March of Dimes. Vernica Zaragovia for NPR  Research has shown that women who consume at least  micrograms of folic acid daily have a significantly reduced risk of having a pregnancy affected by neural tube defects  including spina bifida which can involve paralysis and anencephaly in which large parts of the brain are missing. The catch Folic acid is only protective if consumed in the earliest weeks of pregnancy. Most women by the time they know theyre pregnant theyve already passed that critical window says Dean Appling a biochemistry professor at the University of Texas at Austin. If they had a problem with folic acid it would be too late at that point to prevent the birth defect. Mandating fortification helps ensure that women are getting enough folic acid even before they know they need it. And studies http suggest that fortifying corn masa with folic acid could prevent an additional  to  cases of neural tube defects among babies born to Hispanic mothers each year. So why does the FDA currently ban dosing corn masa flour with folic acid It all has to do with nixtamalization http the process by which tough corn kernels are softened by soaking in an alkaline solution usually of slaked lime. The process which hails from ancient Mesoamerica  whats now Mexico and Central America  dates back thousands of years. It renders the corn more pliable for grinding into masa flour and gives the masa its distinctive aroma and flavor. But the FDA worries that this alkaline treatment could also affect the stability of added folic acid the agency told The Salt in a statement. The FDA is concerned that the breakdown of folic acid in corn masa flour could yield a substance that raises concerns about safety. The March of Dimes and others first petitioned the FDA to allow added folic acid in corn flour masa in . As part of its review the FDA asked the petitioning groups to study whether folic acid would stay stable in corn masa flour. The petitioners filed the results of that study in October. Michael Dunn the Brigham Young University food scientist who led the study cannot comment on the test results while theyre under FDA review but he has previously called them encouraging. As The Seattle Times has reported http Dunns early results suggested no loss of folic acid in fortified masa after three months of storage. The March of Dimes Pellegrini says she believes the FDA will respond to the results of Dunns study later this month. But the FDA might have more questions related to the study before making a final ruling."