Vitamin A supplementation selectively improves the linear growth of Indonesian preschool children: Results from a randomized controlled trial

Background: Vitamin A deficiency is associated with stunting and wasting in preschool children, but vitamin A supplementation trials have not shown a consistent effect on growth. Objective: We examined the effect of vitamin A supplementation on height and weight increments among Indonesian preschool children. Design: Data were obtained from a randomized, double-masked, placebo-controlled trial of rural Javanese children aged 6-48 mo. Children received 206 000 IU vitamin A (103 000 IU if aged < 12 mo) or placebo every 4 mo. Results: High-dose vitamin A supplementation modestly improved the linear growth of the children by 0.16 cm/4 mo. The effect was modified by age, initial vitamin A status, and breast-feeding status. Vitamin A supplementation improved height by 0.10 cm/4 mo in children aged < 24 mo and by 0.22 cm/4 mo in children aged ≥ 24 mo. The vitamin A-supplemented children with an initial serum retinol concentration < 0.35 μmol/L gained 0.39 cm/4 mo more in height and 152 g/4 mo more in weight than did the placebo group. No growth response to vitamin A was found among children with an initial serum retinol concentration ≥0.35 μmol/L. In non-breast-fed children, vitamin A supplementation improved height by 0.21 cm/4 mo regardless of age. In breast-fed children, vitamin A supplementation improved linear growth by ≃0.21 cm/4 mo among children aged ≥24 mo, but had no significant effect on the growth of children aged < 24 mo. Conclusion: High- dose vitamin A supplementation improves the linear growth of children with very low serum retinol and the effect is modified by age and breast-feeding.