Oral zinc supplementation positively affects linear growth, but not weight, in children 6-24 months of age

Childhood zinc deficiency is a common problem in many developing countries where people rely mainly on plant based diets with low zinc contents. Zinc supplementation is one of strategies to combat zinc deficiency and its consequences in children. The aim of this community trial was to examine the effect of zinc supplementation on the linear growth of children 6-24 months of age and to examine the feasibility of its implementation in the context of primary health care (PHC).Rural community health centers providing maternal and child care in two areas with moderate rates of malnutrition were randomly assigned to intervention and control groups, including 393 and 445 children 6-24 months of age, respectively. Children in both groups received routine iron and multivitamin or vitamin A and D supplements through PHC services. Mothers of children in the intervention group were asked to give a single dose of 5 ml/day zinc sulfate syrup (containing 5 mg elemental zinc) to their children for 3 months while children in the control group did not receive the supplement.Anthropometric measurements were performed at baseline and on a monthly basis in both groups. We found a 0.5 cm difference in the height increment in the intervention group as compared with the control (P< 0.001). Zinc supplementation had no effect on weight increment of children.Oral zinc supplementation was found to be both practical and effective in increasing linear growth rate of children less than 2 years of age through PHC.