Effectiveness of zinc supplementation to full term normal infants:A community based Double Blind, Randomized, controlled, clinical trial

The objective of the present study was to test if zinc supplementation initiated early, prevents stunting and promotes optimum body composition in full term infants. Neonates (2-4 months) were enrolled at home. Birth weights were recorded from the delivery records and weights were recorded at enrolment again. Anthropometric data collection like weight, length, head circumference, chest circumference, mid upper arm circumference and skin fold thicknesses at triceps, biceps, subscapular area were collected every three months. Maternal weight and height were recorded 1 month after delivery and every three months. Supplementation of zinc was started from the age of 5 months and continued till the child attained 18 months of age. There were 162 and 154 children in zinc and placebo groups respectively. The total duration of supplementation was for a period of 14 months. The control group of children received only riboflavin 0.5mg per day, whereas the intervention groups received 5 mg of zinc plus riboflavin 0.5mg per day. Blood samples were collected from cubital vein in a sub sample of 70 children at the end of the study, for estimation of Hemoglobin, Zinc, Copper and Vitamin A. Dietary intakes were calculated by 24hours recall method for 78 children. Thirty seven percent of our study mothers were chronically energy deficient. Mean calorie consumption in these infants was 590 cal per day (95% CI 526.3, 653.8) and mean zinc intakes from diets were 0.98 mg/day. Multiple linear regression models demonstrated maternal weight as strong predictor of infants’ weight and length at 18 months age. As expected, diarrhea duration impacted infant’s linear growth and weight gain adversely. Zinc supplementation had no effect on the linear growth, but increased body fat (measure by skin folds) significantly.