More harm than good? Iron supplements have no impact on children’s cognitive function, reveals study

09 Sep 2021 --- A Bangladesh study has concluded that preventive iron treatment has no impact on young children’s development but improves anemia. These findings could inform future global health policy guidelines about the use of iron interventions for hundreds of millions of children worldwide.

“Health economic arguments for universal iron interventions have depended on the assumed presence of functional benefits.” Sant-Rayn Pasricha, lead researcher and joint division head of Population Health and Immunity at WEHI, Australia, tells NutritionInsight.

“By demonstrating no link, the findings will influence the economic case for this policy and may lead to iron not being used as widely in populations.

Additionally, the study evaluated adverse side effects in children who took the iron supplements preventatively. Supplementation was found to “do more harm” in some children.

“In children taking iron supplements who did not have anemia, they may have had increased presentations to clinics due to episodes of diarrhea, possibly indicating iron interventions were doing more harm than good,” says Jena Hamadani, doctor at International Centre for Diarrhoeal Disease Research, Bangladesh.

Guidelines and recommendations
Iron supplements are administered to young children worldwide to prevent anemia, in line with global guidelines.

“In infants between seven to twelve months of age, Australian guidelines suggest 11 mg iron per day and 9 mg in children aged between one to three years. The World Health Organization (WHO) recommends daily iron supplements 12.5 mg per day in this age group, or multiple micronutrient powders containing 10 mg to 12.5 mg of iron,” says Pasricha.Preventive iron treatment has little effect on the development of young children.

The recommendation for iron supplementation was previously linked to a child’s development as “many observational studies (no intervention) had linked anemia to poorer child cognitive development,” he adds.

Last year, the WHO announced new guidelines for detecting iron shortage and overload in youngsters to avoid serious consequences including anemia and developmental delays.

Iron supplementation impact analyzed
The study measured the impact of iron supplements on child cognitive function, behavior and development. The researchers conducted a randomized trial on 3,300 children in rural Bangladesh. Iron was provided to eight-month-old children as iron drops and home fortification packets (multiple micronutrient powders).

“We undertook a systematic review of all previous trials evaluating the effect of iron in young children and found that despite the long-accepted link between iron and positive developmental outcomes, there had not been large trials to address this question. We thus sought to address this gap through the BRISC trial,” explains Pasricha.

The study measured children’s cognitive, language and motor development, behavior and growth, and found iron supplements had no impact on any of these areas of development.

“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 beneficial,” adds Pasricha.

“The study results have implications for how we treat iron deficiency and anemia in babies and young children worldwide.”

The study was funded by 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.The study can inform future global health policy guidelines about the use of iron interventions in young children.

Global health policy
Anemia in young children has 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,” says Pasricha. “Our rigorous study shows this is not the case.”

The WHO recommends iron supplements are given to all young children in low and middle-income countries where anemia is common.

“We need to carefully reconsider the use of these interventions based on this study. “It also puts into question the need to screen otherwise healthy, asymptomatic children for anemia,” adds Pasricha.

“This study may also help inform guidelines for the treatment and prevention of anemia in Indigenous populations in Australia,” concludes Beverley-Ann Biggs, head of the International and Immigrant Health Group, Australia.

Nestlé Research previously developed a five times more absorbent iron compound as compared to traditional stable iron forms.

By Nicole Kerr