Iron pills can make people hungry by improving iron-deficiency anemia, which can cause poor appetite, according to azcentral.com. Except in cases of anemia, iron supplements are not known for increasing or decreasing hunger.
Lack of desire to eat can be a symptom of anemia, especially in babies and children, azcentral.com notes. Children may begin their lives with an iron deficiency because mothers may not have access to iron supplements. Iron deficiency in children can stunt physical and mental development.
Azcentral.com cites a 1994 study of Kenyan children that showed improvement in growth and appetite after 14 weeks of iron supplementation.