National Mandatory Grain Fortification Legislation Decreases Anemia Prevalence among Nonpregnant Women of Reproductive Age: Findings from Multiple Demographic and Health Surveys

Abstract

Two billion people are affected by anemia globally, mostly including women of reproductive age (WRA) and those residing in low- and middle-income countries (LMICs). Large national population-representative studies examining the impact of national grain fortification policies on the prevalence of anemia among WRA are lacking from recent years. We aimed to determine whether mandatory national grain fortification policies reduce the prevalence of anemia among nonpregnant WRA. We examined national food fortification policy characteristics from the Global Fortification Data Exchange (GFDx) database and anemia prevalence data from the Demographic and Health Surveys (DHSs). In total, 21 LMICs, with and without national grain fortification policies, completing ≥2 DHSs between 2000 and 2018, met study eligibility. We applied the difference-in-differences approach to compare changes in the prevalence of anemia among WRA in 10 countries with and 11 countries without fortification between each DHS year. Odds ratios (ORs) and average marginal effects, along with 95% confidence intervals (CIs) were calculated, adjusting for individual-, household-, and country-level factors. Our analytic study sample included 96,334 and 874,984 WRA in countries with and without fortification, respectively. Overall, countries with fortification showed 27% decreased odds of anemia (adjusted OR: 0.73; 95% CI: 0.63, 0.85) and a 7.47-percentage-point decrease in the mean anemia prevalence (average marginal effect: -7.47; 95% CI: -11.03, -3.92) from the pre- to the postfortification period, compared with countries without fortification, after controlling for selected individual-, household-, and country-level factors. Our findings, using nationally representative DHS data and applying a recommended analytic method to measure policy effectiveness, suggest significant reductions in anemia prevalence in WRA in countries with mandatory grain fortification compared with those without. Implementing national mandatory grain fortification in LMICs would effectively reduce anemia resulting from micronutrient deficiencies among WRA.