Effects of vitamin A, vitamin A plus zinc, and multiple micronutrients on anemia in preschool children in Chongqing, China.

This study is to clarify the impact of vitamin A or vitamin A combined with other micronutrients supplementation on anemia and growth in preschoolers. In the present study, a total of 290 preschoolers, aged 36-72 months old were randomly assigned to 3 treatment groups: vitamin A (A group), vitamin A plus zinc (AZ group), and vitamin A combined with additional multiple-micronutrient (AMM group). After 6-month supplementation, the height and height-for-age z-score gains of the AZ group were significantly higher than the other groups; the weight gain of the AMM group was greater than the other groups. Compared with baseline values, the concentrations of hemoglobin, and zinc at the end significantly increased in all 3 groups. The incremental concentrations of hemoglobin in the AMM group were significant higher than in the other two groups. Furthermore, the incremental concentrations of serum retinol in the AMM group, and the increase in serum zinc concentrations in the AZ group were significantly higher, respectively, than in the other groups. These 3 kinds of supplements in the present study are effective in enhancing height gains and are effective in reducing the prevalence of anemia. Supplementation of zinc plus vitamin A is a better way for improving children's height and height-for-age z-score. Vitamin A combined with multiple-micronutrient is more effective in improving the hemoglobin concentrations in preschool children.