Daily iron supplementation on cognitive performance in primary-school-aged children with and without anemia: a meta-analysis.

Anemia is an important public health and clinical problem. Observational studies have linked iron deficiency and anemia in children with many poor outcomes, including impaired cognitive development. In this study, we summarize the evidence for the effect of daily iron supplementation on cognitive performance in primary-school-aged children. We searched electronic databases (including MEDLINE and Wangfang database) and other sources (August 2015) for randomized and quasi-randomized controlled trials involving daily iron supplementation on cognitive performance in children aged 5-12 years. We combined the data using random effects meta-analysis. We identified 3219 studies; of these, we evaluated 5 full-text papers including 1825 children. Iron supplementation cannot improve global cognitive scores (Mean difference 1.05, 95% confidence interval [CI] -2.69 to 4.79, P<0.01). Our analysis suggests that iron supplementation improves global cognitive c outcomes among primary-school-aged children is still unclear.