Was Folic Acid Fortification Successful in Latin America?
The fortification of cereal products in many countries to improve folate status of the population and reduce the number of neural tube defects in infants is considered to be a public health success story. Fortification is likely to be effective in countries in which the folate status of women of childbearing age is low, and according to the Flour Fortification Network, if the incidence of neural tube defects is greater than 1 in 1000 live births. Whereas some countries have had a program in place for over a decade, others are still considering whether to implement a program, or there may be a lack of support politically for mandatory staple food fortification. In Latin America, all countries except Venezuela have legislated micronutrient fortification. The monitoring and evaluation of these actions, however, has been limited. Rosenthal and colleagues recently published a report on neural tube defects in Latin America, and the success of fortification programs there.
The authors searched the scientific literature for reports about neural tube defects in Latin American countries that included more than 5000 live births per year. Most reports came from registries and surveillance systems. There were no adequate reports for five countries: Bolivia, El Salvador, Nicaragua Panama and Paraguay. For seven countries (Argentina, Costa Rica, Cuba, Ecuador, Guatemala, Mexico and Puerto Rico), nationally representative data was available. Brazil, Chile, Colombia, Cuba, Mexico, Uruguay and Venezuela only had information from local or regional hospital registries. While almost all countries have introduced food fortification with folate in the past 15 years, the amount used to fortify varied widely by a factor of ten, from 0.35 mg/kg in El Salvador up to 3.3 mg/kg in Paraguay. The information from Argentina, Brazil, Chile, Costa Rica, Cuba, Puerto Rico and Mexico was sufficient to allow pre- and post-fortification analyses.
There was considerable variation in the rate of neural tube defects by region and country. The total range varied from 0.2 to 9.6 cases per 1000 live births. To compare, the rate of neural tube defects in the United States is 0.6 per 1000 live births, from the Code of Federal Regulations Title 21. National prevalence estimates are considered the most reliable and varied from 0.45 cases per 1000 live births in Costa Rica up to 1.1 cases per 1000 live births in Cuba. Nationally representative hospital discharge data indicated a prevalence of 0.47 in Mexico and 1.62 in Argentina. Regional surveys from other countries showed considerable variation, and some of the data appear questionable. In countries for which time trend data was available, there appeared to be a consistent decline in the number of cases ranging from 3.3% annually in Costa Rica, 7.8% in the Dominican Republic and up to 22% in Guatemala City. The data was sufficient to estimate the effect of fortification in Argentina, Brazil, Chile, Costa Rica, Cuba, Mexico and Puerto Rico. This varied from a 33% reduction in Brazil up to 59% reduction in Mexico.
This study shows that folic acid fortification in Latin American countries has been successful in reducing the numbers of children born with neural tube defects. Even modest reductions in the number of neural tube defects in Latin America, where around 11 million infants are born annually, has reduced the total number of cases in the order of thousands per year. Even so, this article has highlighted significant limitations in the ability to monitor the effect of folate fortification due to a lack of reliable surveillance systems. The article is an excellent source for information on neural tube defects in Latin America, as well as the effectiveness of folate fortification on neural tube defect reduction.
Rosenthal J, Casas J, Taren D, Alverson CJ, Flores A, Frias J. Neural tube defects in Latin America and the impact of fortification: a literature review. Public Health Nutrition. 2014;17(03):537-50. DOI: http://dx.doi.org/10.1017/S1368980013000256
Title 21: Food and Drugs. Chapter I: Food and Drug Administration, Department of Health and Human Services. Subchapter B: Food for human consumption. Part 101: Food labeling. Subpart E: Specific requirements for Health Claims. Section 101.70 Health Claims: Folate and neural tube defects. http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=101.79