Comparative Effectiveness of Weekly Versus Daily Oral Iron Supplementation for the Prevention of Anemia in Non-Anemic Thai Infants Aged 6–12 Months

Abstract

Iron deficiency anemia (IDA) is a critical public health issue that exerts permanent adverse effects on the neurodevelopment of children. Current Thai national policy, which recommends weekly iron supplementation, deviates from the World Health Organization guidelines that advocate for daily administration. This experimental study aimed to 1) compare the effectiveness of daily versus weekly iron supplementation and 2) examine factors associated with the prevention of anemia in Thai children. A double-blinded randomized controlled trial (RCT) was conducted with 96 non-anemic children aged 6 months, who were assigned to receive 12.5 mg of elemental iron either daily or weekly for a period of six months. The results revealed that at 12 months of age, the daily supplementation group had significantly higher mean hemoglobin levels (12.2 g/dL vs. 11.4 g/dL; P-value < 0.001) and serum ferritin levels (45.5 ng/mL vs. 18.2 ng/mL; P-value < 0.001) compared to the weekly group. Most importantly, no children in the daily group were found to have IDA (0.00%), whereas the prevalence in the weekly group reached 16.70% (P-value = 0.006). Regarding associated factors, both groups maintained compliance rates exceeding 90% (P-value = 0.712), with no significant difference in the incidence of adverse effects (P-value = 0.647), indicating that the daily regimen is safe and well-tolerated by children. In conclusion, daily iron supplementation is demonstrably more effective than weekly administration in preventing anemia and iron deficiency in Thai children aged 6 – 12 months. These findings serve as crucial empirical evidence for reconsidering national policies to optimize iron supplementation strategies for maximum effectiveness.