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

Background: 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.

Aim of the study: To ascertain the effect of weekly iron supplementation on the growth and hemoglobin status of non-anemic school-age children.

Subjects and methods: 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.

Results: 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).

Conclusion: 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.