Infant iron deficiency may hinder emotional growth

Iron deficiency during the first year of life appears to adversely impact the social and emotional development of infants, and the presence or absence of anemia does not alter the impact, study findings suggest.

"Iron deficiency without anemia is not generally detected by current screening procedures," Dr. Betsy Lozoff told Reuters Health. The most common form of screening, the hemoglobin test, detects anemia but not iron deficiency, she explained.

If the findings of this small study are confirmed, screening might need to change from the current hemoglobin test to utilizing a complete blood count test.

"A complete blood count gives information about the red cells in addition to hemoglobin and can help diagnose iron deficiency," noted Lozoff, from the University of Michigan, in Ann Arbor.

She and colleagues assessed the social and emotional behavior of 77 otherwise healthy African-American infants who were 9 months old. Testing confirmed 28 of these infants were iron deficient with anemia, 28 were iron deficient without anemia, and 21 had sufficient iron levels.

Regardless of iron status, all infants received a 3 month course of liquid iron sulfate (22 milligrams daily). Among infants with sufficient iron levels, the supplements were to prevent iron deficiency during their transition to being fed unmodified cow's milk, the investigators note in a report in The Journal of Pediatrics

Follow-up social and emotional behavioral assessments revealed that infants with poorer iron status at the age of 12 months, compared with those with sufficient iron levels, were more shy, less likely to be oriented or engaged to their surroundings and other people, and were harder to soothe. These associations held regardless of anemia status.

These results "should be confirmed in larger samples and other populations," Lozoff said.

Nevertheless, these findings contribute to the growing evidence associating early iron deficiency with poor social and emotional development, the investigators conclude.

SOURCE: The Journal of Pediatrics, May 2008