Children with high iron levels may get too much of the nutrient from fortified infant formulas, raising the risk of developmental delays, researchers said.
Spatial memory and hand-eye coordination was worse among children who received additional iron and already had high levels in their blood, researchers wrote today in the Archives of Pediatric & Adolescent Medicine. Smaller “suggestive” reductions in IQ and math skills also were found in the study of 473 Chilean children who were re-evaluated 10 years after initially taking the baby formula.
Iron content in formula is routinely boosted in many parts of the world to avoid anemia and other ills, said the scientists, led by Betsy Lozoff, a pediatrician and professor at the University of Michigan in Ann Arbor. Today’s findings suggest calls for universal iron supplements may need to be reconsidered, the researchers said.
“Iron is an essential nutrient of which both too little and too much are problematic,” Lozoff and her colleagues wrote. “If unneeded iron were absorbed, the brain might be vulnerable to adverse effects.”
The research followed up with infants from Santiago, Chile, who received either iron-fortified or low-iron formula from 1991 to 1994. A decade later, the fortified group showed lower scores on seven tests of developmental abilities, although only the dropoffs in spatial memory and visual-motor coordination were big enough to be statistically significant.
“No change in practice should result from a single study,” the researchers said. Still, “the optimal level of iron in infant formula warrants further study.”