RESUMEN
This study was carried out on 60 breast-fed healthy infants. Their age were within 4 - 9 months. They were divided into 2 equal groups, the infants of the 1st group were given zinc sulfate in a dose equivalent to 5 mg elemental zinc along a period of 90 days and dose of the 2nd group were given a placebo solution for the same period, in addition to breast feeding and usual diet. The weight, length and serum zinc were recorded at the beginning and at the end of the study, which showed high significant increase in the mean weight gain for the supplemented group, but nonsignificant increase in the mean length gain compared with those of the placebo group. Also, there was high significant decrease in the mean serum zinc level for those of the placebo group compared with supplemented group; however, their mean serum zinc was within the normal average for age [65-185 mug/dl], and none of them showed any sign or symptom of zinc deficiency