Modeling Zinc Intake for Intervention and Scenario Analysis

Background: A large number of illnesses, afflicting one-third of the world's population, have been attributed to zinc deficiency. Inadequate dietary intake of bioavailable forms of zinc is considered the most frequent cause of zinc deficiency, which is most common in arid regions of developing countries. Objective: To employ a modeling approach in a test population to analyze how best to eliminate zinc deficiency using different plausible dietary scenarios. Methods: A comprehensive database was built upon food consumption patterns of two population groups residing in a village and a suburb in semiarid central Iran near Isfahan city. A database was created on zinc and phytic acid concentrations of different foods and ingredients consumed by the study populations. A zinc intake model was constructed and parameterized accounting for bioavailability and model input uncertainties. Results: The zinc intake of about one-third of both study populations, which did not differ significantly in their rates of zinc deficiency, was below the Estimated Average Requirement (EAR) for zinc. Scenario analyses predicted that at the current rate of food consumption, it would take up to 60 years for 97.5% of the population to meet their zinc EARs. Fortification of wheat flour and biofortification of wheat grains would result in 93% and 88% of the population, respectively, achieving their EARs in 15 years. Conclusions: The modeled results suggest that fortification and biofortification are the most effective and sustainable strategies to combat zinc deficiency. The methodology developed in this study is general and is shown to be a useful tool for the analysis of possible future trends and intervention scenarios.