Supplemental vitamin A improves anemia and growth in anemic school children in Tanzania

Abstract

We conducted a randomized controlled trial of the effects of dietary supplements on anemia, weight and height in 136 anemic school children from a low socioeconomic background in Bagamoyo District schools in Tanzania. The aim of the current study was to investigate the impact of dietary supplements on anemia and anthropometric indices of anemic school children. The supplements were vitamin A alone, iron and vitamin A, iron alone or placebo, administered in a double-blinded design for 3 mo. All supplements were provided with local corn meals. Hemoglobin concentration, body weight and height were measured at baseline and at follow-up after supplementation. Vitamin A supplementation increased the mean hemoglobin concentration by 13.5 g/L compared with 3.5 g/L for placebo [P < 0.0001, 95% confidence interval (Cl) 6.19-13.57), the mean body weight by 0.6 kg compared with 0.2 kg for placebo (P < 0.0001, 95% Cl 0.19-0.65) and the mean height by 0.4 cm compared with 0.1 cm for placebo (P = 0.0009, 95% Cl 0.08-0.42). However, the group of children who received combined vitamin A and iron supplementation had the greatest improvements in all indicators compared with placebo (18.5 g/L, P < 0.0001, 95% Cl 14.81-22.23; 0.7 kg, P < 0.0001, 95% Cl 0.43-0.88 and 0.4 cm, P < 0.0001, 95% Cl 0.22-0.56 for hemoglobin, weight and height, respectively). It is likely that vitamin A supplementation may have a useful role in combating the problems of vitamin A deficiency and anemia, as well as in improving children's growth, in developing countries.