The effect of adding zinc to vitamin A on IGF-1, bone age and linear growth in stunted children

A randomized, double-blind, placebo controlled trial of a single dose of 200,000 I.U. of vitamin A with daily zinc supplementation was conducted with children in Mojo village, Surabaya City. Children aged 48 to 60 months were randomized to receive a single dose of 200,000 I.U. of vitamin A plus zinc sulfate (n = 12) or a single dose of 200,000 I.U. of vitamin A (n = 12) plus placebo six days a week for six months. Children were evaluated weekly for nutrient intake and for IGF-1, C-reactive protein levels, gamma globulin levels, serum zinc, serum retinol, bone age and the index height for age at six months.At the end of the study, there was a significant increase in the serum retinol level (p < 0.03), serum zinc level (p < 0.03), IGF-1 hormone (p < 0.04) and Z-score height for age (p < 0.001), bone age (p < 0.01), and gamma globulin level (p < 0.04) and a significant decrease in the amount of infection/inflammation measured by CRP level (p < 0.001). There was also a significant correlation between CRP level and height for age (p < 0.01), and between gamma level and height for age (p < 0.01).These results suggest that combined vitamin A and zinc supplementation reduces the risk of infection and increases linear growth among children, and thus may play a key role in controlling infection and stunted growth for children under five years old.