Zinc Adequacy of Preschool Menus: The Implication of Phytate/Zinc Molar Ratios

Abstract

Trends towards a more plant-based diet may alter zinc status of groups with marginal zinc intakes, such as children. Careful menu planning by registered dietitians is critical. The objectives of this study were 1) to determine if the planned menus of licensed child care facilities that participated in Child Care Food Program provided adequate amounts of zinc, and 2)to assess the menus for their phytate content, the known modifier of zinc bioavailability. We contacted 180 child care facilities and randomly selected one week planned menus from 18 facilities (10%) for analysis. The menus were analyzed using a subset of the foods from the Nutrient Database for Nationwide Food Surveys, Release 9. The 5-day average intakes of zinc and other selected nutrients were compared against 1/2 and 2/3 of the Recommended Dietary Allowances (RDAs) established for children 4-6 years of age (there are no RDAs available for ages 3-5). Mean Zinc intakes fell below 1/2 and 2/3 of the RDA. To assess zinc bioavailability as affected by phytate, we calculated phytate to zinc molar ratios for all 18 facilities. Our results showed that phytate to zinc molar ratios were below the critical ratio of 10 for all facilities. In conclusion, the zinc content of the meals that were provided to children participating in the selected childcare facilities did not meet the RDA but that the phytate content of the menus did not inhibit the bioavailability of zinc.