Objectives To examine the effectiveness of weekly iron supplements given for 10 weeks by teachers to children in rural schools in the Philippines.
Methods Forty-nine rural primary schools took part in the study and were randomly assigned to two groups: children in 25 schools received a weekly tablet providing 108 mg iron while children in 24 schools acted as controls. All children were dewormed before the start of the iron supplementation. The haemoglobin concentration of a systematic sample of one in three children in two classes in each school was estimated before and 5–17 weeks after the end of the iron supplementation.
Results A total of 1510 children aged 7–12 years were studied at both surveys. The mean haemoglobin concentration of children in the intervention group did not change significantly; in the untreated group it fell by 3.8 g/l and the prevalence of anaemia rose from 14.3% to 25.6%. The difference between study groups was significantly larger amongst the younger children (7–8 years), and was observed in both anaemic and non-anaemic children.
Conclusion Even where anaemia is only a mild public health problem, weekly iron supplements given by teachers may prevent a fall in the haemoglobin concentration, and can benefit both anaemic and non-anaemic children.