Consumption of Micronutrient Powder, Syrup or Fortified Food Significantly Improves Zinc and Iron Status in Young Mexican Children: A Cluster Randomized Trial

The objective of this study was to compare the effect of three micronutrient products on biomarkers of iron and zinc status of Mexican children 6–12 months of age. As part of research to improve the impact of a national program, 54 communities were randomly assigned to receive: (1) fortified food (FF), provided by the program at the time, or (2) micronutrient powders (MNP) or (3) syrup. Each product contained 10 mg each of zinc and iron, plus other micronutrients. Children consumed the product 6 days/week for four months. Primary outcomes were changes in serum zinc, ferritin, soluble transferrin receptor, hemoglobin concentrations, and their deficiencies. Zinc concentration increased significantly from baseline to follow-up in all groups, with the largest change in the syrup group (geometric mean difference: +4.4 µmol/L; 95%CI: 3.2, 5.5), followed by MNP (+2.9 µmol/L; 95%CI: 2.1, 3.6) and FF (+0.9 µmol/L; 95%CI: 0.3, 1.6). There was a significant increase in hemoglobin concentration (+5.5 g/L; 2.5, 8.4) and a significant reduction in anemia prevalence (44.2% to 26.8%, p < 0.01) only in the MNP group. Compliance differed significantly among groups (MNP vs. FF, p = 0.04; MNP vs. syrup, p = 0.04), but may not fully explain the greater improvement in zinc and iron status in the syrup and MNP groups. The food matrix may influence nutrient utilization from supplements.