Objective: To study the relationship between micronutrient supplementation and children growth.
Methods: A double-blind, placebo-controlled trial was conducted in 156 growth retarded preschool children. They were randomly assigned to five groups: supplemental control (S-control, n = 28), zinc supplementation (+Zn, 3.5 mg Zn/day, n = 34), zinc and calcium supplementation (+ZnCa, 3.5 mg Zn + 250 mg Ca/day, n = 37), zinc and calcium and vitamin A supplementation (+ZnCaVA, 3.5 mg Zn + 250 mg Ca + 200 g VA/day, n = 28), Calcium, and vitamin A supplementation (+CaVA, 250 mg Ca + 200 g VA/day, n = 29). Another 34 children with normal height were selected as normal control (N-control). Supplementation continued for twelve months.
Results: The height gain in +Zn group (7.84 cm per year) and +ZnCa group (7.70 cm per year) was significantly higher than that in S-control group (6.74 cm per year, P < 0.05); The weight gain in +ZnCaVA group (2.55 kg per year) and +CaVA group (2.57 kg per year) was also significantly higher than that in S-control group (2.19 kg per year, P < 0.05); The average days of illness in each supplementation group were lower than that in S-control (13 days per year compared with 23 days per year). No significant difference was observed on bone age.
Conclusion: Zinc and Zinc + Calcium supplementation can improve the height gain, and vitamin A can improve weight gain in growth retarded preschool children, but do not affect the maturity of bone. Micronutrient supplementation can lower the morbidity of these children.