Impact of Voluntary Folic Acid Fortification of Corn Masa Flour on RBC Folate Concentrations in the U.S. (NHANES 2011–2018)

Abstract

Surveillance data have highlighted continued disparities in neural tube defects (NTDs) by race-ethnicity in the United States. Starting in 2016, the Food and Drug Administration (FDA) authorized voluntary folic acid fortification of corn masa flour to reduce the risk of neural tube defects (NTDs) among infants of Hispanic women of reproductive age. To assess the impact of voluntary corn masa fortification, cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) 2011–2018 for Hispanic women of reproductive age with available red blood cell (RBC) folate concentrations were analyzed, with additional analyses conducted among Hispanic women whose sole source of folic acid intake was fortified foods (enriched cereal grain products (ECGP) only), excluding ready-to-eat cereals and supplements. RBC folate concentration (adjusted geometric mean) among Hispanic women of reproductive age did not differ between 2011–2016 and 2017–2018, though RBC folate concentration increased significantly among lesser acculturated Hispanic women consuming ECGP only. Concentrations of RBC folate for those born outside the U.S and residing in the U.S <15 years increased from 894 nmol/L (95% CI: 844–946) in 2011–2016 to 1018 nmol/L (95% CI: 982–1162; p < 0.001) in 2017–2018. Primarily Spanish-speaking Hispanic women of reproductive age who only consumed ECGP saw an increase from 941 nmol/L (95% CI: 895–990) in 2011–2016 to 1034 nmol/L (95% CI: 966–1107; p = 0.03) in 2017–2018. By subpopulation, we observed no significant changes in the proportion at risk of NTDs (<748 nmol/L) and no changes in the model-based estimated NTD rates following voluntary corn masa fortification. This analysis suggests that there is a remaining risk among Hispanics for folate sensitive NTDs, though continued monitoring of folate status in future NHANES data cycles will help inform the long-term efficacy of voluntary fortification of corn masa flour.

Update on the impact of voluntary folic acid fortification of corn masa flour on red blood cell folate concentrations—National Health and Nutrition Examination Survey, 2011–March 2020

“…However, these improvements in RBC folate concentrations did not significantly shift the proportion of women into OBF concentrations, limiting the impact of voluntary fortification on NTD prevention. Overall, these updated results are consistent with the previous report on the lack of impact of voluntary corn masa fortification on folate status among Hispanic WRA (Wang et al, 2021). These results may support the conclusions of previous studies suggesting that very few manufacturers have introduced CMF product fortified with folic acid since the introduction of voluntary fortification (Kancherla et al, 2019; Redpath et al, 2018).…”

“…The World Health Organization established an optimal RBC folate concentration threshold for NTD prevention of 906 nmol/L (calculated with the Molloy method of microbiologic assay, equivalent to 748 nmol/L with the CDC assay method) (Cordero et al, 2015; Pfeiffer et al, 2016). Using data from the National Health and Nutrition Examination Survey (NHANES) 2011–March 2020 (data collection ended in March 2020 due to the COVID‐19 pandemic), we analyzed the estimated usual intake of folic acid and RBC folate statuses of Hispanic WRA following the introduction of voluntary fortification of CMF products, providing an update to previously reported results with additional years of data (Wang et al, 2021).…”

Association between maternal prepregnancy diabetes mellitus and preconception folic acid supplement use by Hispanic ethnicity: Findings from Georgia, New York City, and Puerto Rico PRAMS 2016–2018

“…Nonetheless, studies conducted suggest that the voluntary fortification of corn masa has failed to increase the availability of corn masa flour products fortified with folic acid (Kancherla, Averbach, & Oakley Jr., 2019;Redpath, Kancherla, & Oakley Jr., 2018). Additionally, a study assessing the RBC folate concentrations of Hispanic women of reproductive age found that these concentrations did not differ pre-and post-FDA approval of voluntary corn masa fortification (Wang et al, 2021). Mandatory folic acid fortification of corn masa flour products is needed to improve blood Our study has some limitations.…”

“…Case et al (2007) reported no significant difference in daily folic acid supplementation between diabetic and nondiabetic women of childbearing age in a population-based study in Texas. In 2016, the US Food and Drug Administration (FDA) authorized voluntary folic acid fortification of corn masa flour products with folic acid to reduce the risk of NTDs among Hispanics; however, post-voluntary fortification evaluation showed no significant increases in the blood folate concentrations among Hispanics in the United States (Wang et al, 2021).…”

Gestational diabetes mellitus is associated with distinct folate‐related metabolites in early and mid‐pregnancy: A prospective cohort study

“…Numerous countries have implemented programs to increase FA consumption through supplements and fortified foods. 38,39 Since 2009, China has had a nationwide FA supplementation programme. 40 However, insufficient FA intake remains a common problem throughout the world, including in China, 40,41 the Unites states, [42][43][44] Australia, 45 and Canada, 46 and other countries.…”