Effect of iron therapy on behavior performance in nonanemic, iron-deficient infants.

In an effort to determine whether iron deficiency, in the absence of anemia (hemoglobin greater than 11.0 g/dL), might produce alterations in behavioral development, four groups of nonanemic infants, 9 to 12 months of age, with varying degrees of iron deficiency were studied. Infants were classified as iron sufficient, iron depleted, or iron deficient based on measurements of serum ferritin concentration, erythrocyte protoporphyrin values, and the mean cell volume of erythrocytes. Subjects in each group were tested with the Bayley Mental Development Index, treated with parenteral iron, and retested seven days later. The administration of iron produced a significant increase in the Mental Development Index scores (+21.6 points) in the infants with iron deficiency but no significant change in the scores of infants with iron sufficiency (+6.2 points) or only iron depletion (+5.6 points). It is concluded that iron deficiency, even in the absence of anemia, results in biochemical alterations that impair behavior in infants.