UMEÅ, Sweden—Low birth weight infants who supplemented with iron had fewer behavioral problems compared to infants who didn't take iron in a new study from Umeå University in Sweden (Pediatrics 2012 Dec 10. DOI: 10.1542/peds.2012-0989). However, the researchers found early iron supplementation did not affect cognitive functions at 3.5 years of age.
The researchers noted low birth weight infants are at increased risk of cognitive and behavioral problems and at risk for iron deficiency, which is associated with impaired neurodevelopment. Therefore, they conducted a randomized controlled trial in 285 marginally low birth weight infants (2,000 to 2,500 g) infants received who received 0, 1, or 2 mg/kg/day of iron supplements from six weeks to six months of age. At 3.5 years of age, these infants and 95 normal birth weight controls were assessed with a psychometric test (Wechsler Preschool and Primary Scale of Intelligence) and a questionnaire of behavioral problems (Child Behavior Checklist; CBCL). CBCL measures maladaptive behavioral and emotional problems in children, such as internalizing (i.e., anxious, depressiv, and overcontrolled) and externalizing (i.e., aggressive, hyperactive, noncompliant and undercontrolled) behaviors.
Children who received the supplement had better CBCL scores, indicating fewer behavioral problems. Almost 13 percent (12.7 percent) of the children who received no iron had scored a above the U.S. subclinical compared to 2.9 percent and 2.7 percent in 1-mg and 2-mg groups, respectively (P = 0.027).
However, the researchers found no significant differences in IQ between the groups.
Iron levels are low in the United States, according to a report from the Centers for Disease Control and Prevention (CDC). The nutrient has also shown to reduce fatigue in women and increase fitness in teenagers.