Effects of iron supplementation on cognitive development in school-age children: Systematic review and meta-analysis

Befikadu Tariku Gutema; Muluken Bekele Sorrie; Nega Degefa Megersa; Gesila Endashaw Yesera; Yordanos Gizachew Yeshitila; Nele S Pauwels; Stefaan De Henauw; Souheila Abbeddou

doi:10.1371/journal.pone.0287703

Effects of iron supplementation on cognitive development in school-age children: Systematic review and meta-analysis

PLoS One. 2023 Jun 27;18(6):e0287703. doi: 10.1371/journal.pone.0287703. eCollection 2023.

Authors

Befikadu Tariku Gutema^{1

2}, Muluken Bekele Sorrie¹, Nega Degefa Megersa³, Gesila Endashaw Yesera³, Yordanos Gizachew Yeshitila³, Nele S Pauwels⁴, Stefaan De Henauw², Souheila Abbeddou²

Affiliations

¹ School of Public Health, Arba Minch University, Arba Minch, Ethiopia.
² Public Health Nutrition Unit, Department of Public Health and Primary Care, Ghent University, Ghent, Belgium.
³ School of Nursing, Arba Minch University, Arba Minch, Ethiopia.
⁴ Knowledge Centre for Health Ghent, Ghent University Hospital, Ghent, Belgium.

Abstract

Background: Iron deficiency is negatively associated with children's cognitive development. Evidence showed that iron supplementation improves cognitive development. Nearly 50% of anemia is caused by iron deficiency. Anemia affects more school-age children, at an age where their brain development continues. The aim of this systematic review and meta-analysis is to review the evidence from published randomized controlled trials to evaluate the effects of iron supplementation on cognitive development and function among school-age children.

Method: Five databases including MEDLINE, EMBASE, Scopus, Web of Science and CENTRAL were used to search for articles on April 20th, 2021. The search was reconducted on October 13th, 2022 to retrieve new records. Studies were eligible if they included school children 6-12 years of age, were randomized controlled trials, and if they tested iron supplementation and measured cognitive development.

Result: Thirteen articles were included in the systematic review. Overall, iron supplementation significantly improved intelligence (standardized mean difference, 95% confidence interval) (SMD 0.46, 95%CI: 0.19, 0.73, P<0.001), attention and concentration (SMD 0.44, 95%CI: 0.07, 0.81, P = 0.02) and memory (SMD 0.44, 95%CI: 0.21, 0.67, P <0.001) of school-age children. There was no significant effect of iron supplementation on school achievement of school-age children (SMD 0.06, 95%CI: -0.15, 0.26, P = 0.56). In a subgroup analysis, iron-supplemented children who were anemic at baseline had had better outcomes of intelligence (SMD 0.79, 95%CI: 0.41, 1.16, P = 0.001) and memory (SMD 0.47, 95%CI: 0.13, 0.81; P = 0.006).

Conclusion: Iron supplementation has a significant positive effect on the intelligence, attention and concentration, and the memory of school-age children but there was no evidence on the effect of iron supplementation on their school achievement.

Copyright: © 2023 Gutema et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Publication types

Meta-Analysis
Systematic Review
Research Support, Non-U.S. Gov't

MeSH terms

Anemia*
Child
Cognition
Dietary Supplements
Humans
Iron / pharmacology
Iron Deficiencies*
Randomized Controlled Trials as Topic

Substances

Iron

Grants and funding

This work was conducted under the PhD studies of BTG, whose scholarship was partially funded by the Flemish Interuniversity Council (VLIR-UOS) in the context of the Institutional University Cooperation Program (IUC) with Arba Minch University https://www.vliruos.be/en/projects/project/22?pid=3604. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.