Iron deficiency is the most common known nutrient deficiency and cause of anemia in childhood. It is associated with numerous adverse health effects, particularly delayed mental and motor development, that may be irreversible. Despite advances of iron nutrition, the prevalence of iron deficiency remains high among low-income infants and toddlers. Previous studies suggest adherence with iron containing drops is low. Adherence to iron sprinkles among children as tested in studies in less developed countries appears high.