Global Coverage of Mandatory Large-Scale Food Fortification Programs: A Systematic Review and Meta-Analysis.

Food fortification with micronutrients is widely implemented to reduce micronutrient deficiencies and related outcomes. Although many factors affect the success of fortification programs, high population coverage is needed to have a public health impact. We aimed to provide recent global coverage estimates of salt, wheat flour, vegetable oil, maize flour, rice, and sugar among countries with mandatory fortification legislation. The indicators were the proportion of households consuming the: food, fortifiable food (that is, industrially processed), fortified food (to any extent), and adequately fortified food (according to national or international standards). We estimated the number of individuals reached with fortified foods. We systematically retrieved and reviewed all applicable evidence from: published reports and articles from January 2010 to August 2021, survey lists/databases from key organizations, and reports/literature received from key informants. We analyzed data with R statistical package using random-effects meta-analysis models. An estimated 94.4% of households consumed salt, 78.4% consumed fortified salt (4.2 billion people), and 48.6% consumed adequately fortified salt in 64, 84, and 31 countries, respectively. Additionally, 77.4% of households consumed wheat flour, 61.6% consumed fortifiable wheat flour, and 47.1% consumed fortified wheat flour (66.2 million people) in 15, 8, and 10 countries, respectively, and 87.0% consumed vegetable oil, 86.7% consumed fortifiable oil, and 40.1% consumed fortified oil (123.9 million people) in 10, 7, and 5 countries, respectively. Data on adequately fortified wheat flour and vegetable oil and coverage indicators for maize flour, rice, and sugar were limited. There are major data gaps on fortification coverage for most foods except salt. All countries with mandatory fortification programs should generate and use more coverage data to assess program performance and adjust programs as needed to realize their potential to reduce micronutrient deficiencies (PROSPERO CRD42021269364).

Preventive small-quantity lipid-based nutrient supplements reduce severe wasting and severe stunting among young children: an individual participant data meta-analysis of randomized controlled trials.

BACKGROUND: Meta-analyses show that small-quantity lipid-based nutrient supplements (SQ-LNSs) reduce child wasting and stunting. There is little information regarding effects on severe wasting or stunting. OBJECTIVES: We aimed to identify the effect of SQ-LNSs on prevalence of severe wasting (weight-for-length z score < -3) and severe stunting (length-for-age z score < -3). METHODS: We conducted a 2-stage meta-analysis of individual participant data from 14 randomized controlled trials of SQ-LNSs provided to children 6-24 mo of age. We generated study-specific and subgroup estimates of SQ-LNS compared with control and pooled the estimates using fixed-effects models. We used random-effects meta-regression to examine study-level effect modifiers. In sensitivity analyses, we examined whether results differed depending on study arm inclusion criteria and types of comparisons. RESULTS: SQ-LNS provision led to a relative reduction of 31% in severe wasting [prevalence ratio (PR): 0.69; 95% CI: 0.55, 0.86; n = 34,373] and 17% in severe stunting (PR: 0.83; 95% CI: 0.78, 0.90; n = 36,795) at endline. Results were similar in most of the sensitivity analyses but somewhat attenuated when comparisons using passive control arms were excluded (PR: 0.74; 95% CI: 0.57, 0.96; n = 26,327 for severe wasting and PR: 0.88; 95% CI: 0.81, 0.95; n = 28,742 for severe stunting). Study-level characteristics generally did not significantly modify the effects of SQ-LNSs, but results suggested greater effects of SQ-LNSs in sites with greater burdens of wasting or stunting, or with poorer water quality or sanitation. CONCLUSIONS: Including SQ-LNSs in preventive interventions to promote healthy child growth and development is likely to reduce rates of severe wasting and stunting. This meta-analysis was registered at www.crd.york.ac.uk/PROSPERO as CRD42019146592.