Effect of Zinc and Vitamin A Supplementation on Diarrhea, Physical Growth and Immune Response in Malnourished Children

Zinc deficiency is common in developing country children, as food intakes are often low, foods from animal sources are infrequently used, the bioavailability of zinc from staple cereal-based diets is limited and zinc losses occur during recurring diarrheal illnesses. Zinc deficiency is associated with impairment in immunological and other defenses against infection and increased rates of serious infections. Due to limitations in currently used biochemical markers, supplementation trials in populations likely to be deficient provide a reliable means of assessing health consequences of zinc deficiency. A significantly lower incidence and prevalence of diarrhea has been observed in zinc supplemented developing country children in several placebo-controlled trials. The effect of routine zinc supplementation on lower respiratory tract infection is still unclear. We, therefore, evaluated the impact of daily zinc supplementation in a representative sample of children aged 6 to 30 months enrolled from a New Delhi slum area, with a sample size sufficient to determine the impact on the incidence of severe diarrhea and acute lower respiratory infection.