A yellow light for iron supplements?

While iron supplements can spur the growth of anemic children and boost their attention spans, excess iron may actually retard the growth of children whose diets contain adequate amounts of the element, a new study suggests.

Ponpon Idjradinata of Padjadjaran University in Bandung, Indonesia, and his colleagues provided a cherry-flavored syrup for 4 months to 47 iron-sufficient toddlers from middle-class urban families. They gave 24 of the tots syrup fortified with 3 milligrams of iron daily; the rest received ironfree syrup.

The unsupplemented children gained weight roughly 50 percent faster than those receiving fortified syrup, Idjradinata's team reports in the May 21 LANCET. Though the study was too brief to pick up any iron-related changes in height, the researchers suggest that such long-term effects cannot be ruled out. Indeed, they conclude, "The assumption that iron supplementation of [all children] is harmless may not be valid."