(P07-036-25) Use of Existing Data Systems to Assess the Impact of Food Fortification With Folic Acid on the Prevalence of Neural Tube Defects

Objectives: Seventy countries included folic acid in their standards for the obligatory fortification of wheat flour, maize flour, or rice.

The objective of this presentation is to share how existing data-collection systems (namely, birth defect surveillance systems) are used to inform the impact of food fortification.

Methods: We reviewed the Global Fortification Data Exchange (GFDx) website for studies that reported neural tube defects (NTDs) as an outcome in countries with mandatory fortification of wheat flour, maize flour, and/or rice. For studies to be included in the GFDx, they had to report pre- and post-fortification data using the same numerator (e.g., number of spina bifida cases) and denominator (e.g., live births and still births).

We assessed studies for the following information: was a birth defect surveillance system used to gather neural tube defect information (yes/no) and if yes, what were the NTD-prevalence results?

Results: As of January 2025, 11 of 70 countries with mandatory fortification of wheat flour, maize flour, and/or rice that include folic acid in their fortification standards, have studies comparing NTDs before and after mandatory fortification was enacted. According to the World Bank, the countries are upper middle- or high-income countries.

In each of the countries, from 1 to 7 studies have been published on the relationship between fortification and NTDs. The studies were conducted between 2 and 16 years after fortification with folic acid was enacted in each country.

NTD data were reported as part of a birth defect surveillance system in at least one study in 9 of the countries.

In every country, NTDs decreased from the pre- to the post-fortification period.

Conclusions: Approximately 15% of countries that mandate fortification of a food with folic acid were found to have NTD impact data. Most of these countries used existing data-collection systems to report NTD information in the pre- and post-fortification periods. In every country, NTDs decreased after fortification with folic acid. For countries that mandate fortification and which have existing data-collection systems, there is an opportunity to use such systems to assess the performance of their fortification programs.

Funding Sources: Bill & Melinda Gates Foundation (INV-058758)