Preschool micronutrient supplementation effects on intellectual and motor function in school-aged Nepalese children

Abstract

Objective: To examine intellectual and motor functioning of children who received micronutrient supplementation from 12 to 35 months of age.

Design: Cohort follow-up of children 7 to 9 years of age who participated in a 2 × 2 factorial, placebo-controlled, randomized trial from October 2001 through January 2006.

Setting: Rural Nepal.

Participants: A total of 734 children 12 to 35 months of age at supplementation and 7 to 9 years of age at testing.

Interventions: Children received iron plus folic acid (12.5 mg of iron and 50 μg of folic acid); zinc (10 mg); iron plus folic acid and zinc; or placebo.

Main outcome measures: Intellectual, motor, and executive function.

Results: In both the unadjusted and adjusted analyses, iron plus folic acid supplementation had no effect overall or on any individual outcome measures being tested. In the unadjusted analysis, zinc supplementation had an overall effect, although none of the individual test score differences were significant. In the adjusted analysis, the overall difference was not significant.

Conclusion: In rural Nepal, we found that iron plus folic acid or zinc supplementation during the preschool years had no effect on aspects of intellectual, executive, and motor function at 7 to 9 years of age, suggesting no long-term developmental benefit of iron or zinc supplementation during 12 to 35 months of age.