School-administered weekly iron supplementation--effect on the growth and hemoglobin status of non-anemic Bolivian school-age children. A randomized placebo-controlled trial.

Abstract

Recent data suggest that daily iron supplementation of iron-replete children could impair their growth. If verified for weekly iron supplementation these results would markedly complicate targeting and implementing school-based weekly iron supplementation programs. To ascertain the effect of weekly iron supplementation on the growth and hemoglobin status of non-anemic school-age children. 73 Bolivian non-anemic school-age children randomly assigned to the treatment group (n = 37; receiving supplements containing FeSO4 during 18 weeks) or the control group (n = 36; receiving a placebo during the same period). Hemoglobin concentration and anthropometric measures were determined for each child at the beginning (T0) and the end (T18) of the study. The treatment group did not show any significant variation in hemoglobin concentration between T0 and T18 (-1.6 +/- 10.4 g/L; P = 0.40) whereas the control group showed a significant decrease in hemoglobin concentration (-4.6 +/- 10.9 g/L; P = 0.03). Anthropometric changes were not significantly different between the treatment and the control groups for weight, (1.63 +/- 1.11 kg vs 1.88 +/- 0.79 kg; P = 0.30), height (2.35 +/- 0.94 cm vs 2.11 +/- 1.03 cm; P = 0.34) or mid-upper arm circumference (0.29 +/- 0.57 cm vs 0.22 +/- 0.54 cm; P = 0.64). In our study, weekly iron supplementation of non-anemic school-age children had no negative effect on their growth while having a positive effect in preventing significant decreases in hemoglobin concentration. These results suggest that in regions where iron deficiency anemia (IDA) is prevalent, a simple and cost-effective way to control IDA in school-age children is to give weekly iron supplements to all children at school.