CSPI often leverages data for advocacy wins. Our science-based approach to advocacy is exemplified in a recent win related to corn masa fortification.  


Gruma, a multinational corn flour and tortilla manufacturing company, was part of a multi-stakeholder coalition that helped push the U.S. Food and Drug Administration (FDA) to allow folic acid fortification of corn masa flour in 2016. Folic acid fortification is important because it can help prevent serious birth defects like spina bifida and anencephaly. Corn masa fortification is particularly important because rates of these birth defects are higher among Latine people in the United States who are also the primary consumers of corn masa flour (the main ingredient in corn tortillas, tamales, sopes, pupusas, and other foods with Mexican and Latin American origins). 

FDA’s corn masa fortification policy is a voluntary policy, meaning it is only successful if companies choose to implement it. Unfortunately, studies published in 2018 and 2019 suggested that few companies were implementing the policy and that even Gruma was not fortifying all of its corn masa products. 


CSPI first reached out to Gruma in February 2020, crediting their prior efforts and requesting a call to discuss how we could help with any ongoing barriers to fortification. We followed up in May and June 2020, but never received any response from the company to our friendly “carrot” approach.  

We realized we needed a “stick,” and sometimes data makes the perfect stick! We decided to develop a report analyzing the folic acid content of a large sample of corn masa products sold in the United States and naming which companies are fortifying their products—and which are not. Whereas the previous studies looked at smaller convenience samples of about 40 products, we obtained a national dataset with 59 corn masa flour products and 476 corn tortilla products. Several of the flour products and over 100 of the tortilla products were made by Gruma, and our study found that only half of Gruma’s flours and none of its tortillas contained folic acid. 

We wanted to give Gruma a chance to do better. Rather than go to press with our findings, we reached out to Gruma in October 2022, giving them a chance to respond before we published our findings. After almost two years of radio silence, the company responded within a few days! They asked for some additional time to respond. After about two months, the company provided a comprehensive reply. 

Results (Success!) 

In response to our outreach, in which we shared our evidence-based findings about the state of corn masa fortification, Gruma made two critical commitments: 

  1. Gruma agreed to fortify its remaining corn masa flour products by 2024 
  2. Gruma agreed to begin fortifying its core corn tortilla brands (such as Mission tortillas) by 2024 

This success highlights the power of data to affect change. 

We hope that Gruma’s commitments will inspire action from other corn masa manufacturers, and look forward to reassessing the status of U.S. corn masa fortification in 2025. The data will tell us if Gruma has followed through on its promises.  

To read CSPI’s full report on corn masa fortification, click here for the English version and aquí para Español. 

To read our factsheet that summarizes the call for corn masa fortification, click here for the English version and aquí para Español.