Once weekly low-dose iron supplementation effectively improved iron status in adolescent girls.

Iron supplementation has been suggested as a strategy for prevention and treatment of iron deficiency (ID) and iron deficiency anemia (IDA) in many countries, but non-compliance of daily regimens and common dosage remain as major challenges. The aim of this study was to investigate the effects of low dose once weekly iron supplementation in adolescent girls. The study was designed as a community-based, randomized, supplementation trial. The initial sample consisted of 200 female high school students, aged 14-16 years old, of whom 193 students concluded the study. They were randomly selected and assigned into either iron-supplemented group (ISG) or iron-unsupplemented group (IUG). The ISG received 150 mg ferrous sulfate once weekly for 16 weeks, whereas the IUG received nothing. Weight, height, and hematological parameters were measured and compared between the two groups before and after the intervention. There was no significant difference between the initial measures of the two groups before the intervention. After 16 weeks of intervention, mean of hemoglobin and serum ferritin improved significantly in ISG compared to IUG. At the beginning of the study, percent of anemia, IDA, and ID in ISG were 12.5%, 8.3%, and 30.2%, whereas these figures for IUG in this period of study were 14.4, 10.3, and 38.2, respectively, which were not significantly different between the two groups. However, percentages of the above items at the end of study in ISG were 2.1%, 0%, and 21.9%, respectively. In contrast to IUG, all cases of IDA were abolished in the ISG. Our study showed that once weekly supplementation of 150 mg ferrous sulfate for 16 weeks significantly improved iron status in female adolescents and effectively treated IDA. There is no need for higher dosage of iron for supplementation that may cause adverse effects and bear higher costs.