Iron supplements not linked to cognitive improvements for kids

08 September 2021
A study in rural Bangladesh has concluded that preventive iron treatment has no impact on young children’s development.

Iron supplements are administered to young children worldwide to prevent anaemia, in line with global guidelines.

Led by WEHI Associate Professor Sant-Rayn Pasricha, in collaboration with Dr Jena Hamadani from the International Center for Diarrheal Diseases Research Bangladesh and Professor Beverley-Ann Biggs from the Doherty Institute, and published in the New England Journal of Medicine, the study measured the impact of iron supplements on child cognitive function, behaviour and development.

At a glance

  • A randomised controlled trial of 3300 children in rural Bangladesh has concluded that while iron supplements improve anaemia in children, these interventions had no impact on cognitive function, behaviour or development.
  • This study is expected to help inform future global health policy guidelines about the use of iron interventions for hundreds of millions of children worldwide.

Supplements show no impact on development

Mother with children in Bangladesh
Mother and children in Bangladesh

Iron was provided to eight-month-old children, as both iron drops and home fortification packets (multiple micronutrient powders), and neither intervention improved child development, although both improved anaemia.

The study measured children’s cognitive, language and motor development, as well as behaviour, and growth, including height and weight, and found iron supplements had no impact on any of these areas of development. 

Associate Professor Pasricha said the research could lead to major changes in global nutrition policy.

“We have been administering iron supplements to young children worldwide for decades in the belief that it had a positive impact on their development, without proper evidence it was actually beneficial,” he said.

“What we have demonstrated, is that while iron supplements improved anaemia in children, these interventions had no impact on growth, cognitive function, behaviour or development.”

“This has implications for how we treat iron deficiency and anaemia in babies and young children worldwide.”


Guiding future global health policy

Associate Professor Pasricha said anaemia in young children has long been linked with poor health outcomes and developmental delays.

“This led to policies of universal distribution of iron interventions to children, based on the assumption that iron would reverse poor child development,” he said. “Our rigorous study shows this is not the case.”

The study also evaluated adverse side effects in children who took the iron supplements preventatively.

Dr Hamadani said for some of these children the supplements may do more harm than good.

“In children taking iron supplements who did not have anaemia, they may actually have had increased presentations to clinics due to episodes of diarrhoea, possibly indicating iron interventions were doing more harm than good,” she said.

The World Health Organization (WHO) recommends iron supplements are given to all young children in low and middle-income countries where anaemia is common.

“We need to carefully reconsider the use of these interventions based on this study,” Associate Professor Pasricha said.

“It also puts into question the need to screen otherwise healthy, asymptomatic children for anaemia.”

Professor Biggs said she expected the findings to inform future global health policy guidelines about the use of iron interventions in young children.

“This study may also help inform guidelines for the treatment and prevention of anaemia in Indigenous populations in Australia,” she said.  

This work was made possible with funding from the Australian National Health and Medical Research Council, the Government of Bangladesh, Global Affairs Canada, the Swedish International Development Cooperation Agency and the Victorian Government, with support from the Foreign, Commonwealth and Development Office in the United Kingdom.


WEHI authors: Sant-Rayn Pasricha, Sabine Braat, Leila Larson and Andrew Baldi.

Title: Benefits and Risks of Universal Iron Interventions in Infants

Published in New England Journal of Medicine, DOI: https://www.10.1056/NEJMoa2034187


Support us

Together we can create a brighter future

Your support will help WEHI’s researchers make discoveries and find treatments to ensure healthier, longer lives for you and your loved ones.

Sign up to our quarterly newsletter Illuminate

Find out about recent discoveries, community supporters and more.

Illuminate Summer 2023
View the current issue