Iron deficiency in infants and children - the current research challenges.

PURPOSE OF REVIEW: Iron deficiency (ID) affects one in five children before they reach preschool age. Existing evidence on ID contributing to suboptimal development and neurodevelopmental disorders come mostly from mechanistic and observational studies. Recommendations for screening and treatment are diverging, emphasizing the knowledge gap. The purpose of this review is to summarize recent evidence on ID in infants and children, its possible role in developmental disorders, and effects of iron supplementation.

RECENT FINDINGS: Recent well powered randomized controlled trials showed no effect of early iron supplementation on psychomotor development in infants, neither in populations at high nor low risk of ID. Treatment of nonanemic ID in children 1-3 years did not improve their cognitive scores. Evidence from observational and imaging studies suggests association of brain ID and attention deficit hyperactivity disorder in children (ADHD).

SUMMARY: Universal prophylactic iron supplementation in infants is not supported by current evidence. Whether non anemic ID needs to be treated is uncertain and so is the legitimacy and timing of screening for ID and anemia. The role of ID and iron availability for the brain in pathogenesis of neurodevelopmental conditions such as ADHD requires further studies.