There's evidence that iron supplements may help reduce behavior problems in young children.
Researchers in Sweden say babies who were born with a low birth weight -- but were otherwise healthy -- were less likely to show signs of behavior problems at age 3 if they were given iron supplements as newborns.
Doctors say more research needs to be done, and warn against giving newborns any supplements unless directed by a pediatrician.
The supplements did not appear to have any impact on tests of intelligence.