Iron and DHA in Relation to Early Cognitive Development

Abstract

Iron and docosahexaenoic acid (DHA) are important nutrients for brain development. Negative effects of DHA supplementation when status of both nutrients is low have been shown on cognitive outcomes. We sought to determine if DHA status interacts with iron deficiency (ID) and influences offspring cognition among a sample of women randomized to DHA during pregnancy. ID was identified by ELISA; DHA status by gas liquid chromatography. ID was assessed by serum transferrin receptor (sTfR), serum ferritin (SF), and body iron (BI); DHA by median split. Bayley Scales of Infant Development Index II (BSID-II) Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) at 18 months (n=191) were assessed. A priori comparisons observed MDI scores (mean ± SD) of 90.1±7.3 and 98.2±9.4, t=2.07, p=0.054 among mothers with ID, low DHA and ID, normal DHA. This trend suggests a protective effect of higher DHA status in ID pregnancy on the BSID-II MDI.