Several possible mechanisms link iron deficiency anemia (low levels of iron in the blood) with poor mental development in children.
Studies have shown that compared to children without anemia, anemic children tend to move around and explore their environment less, which may lead to developmental delays, poor school achievement, and behavior problems.
However, it is difficult to separate the effects of iron deficiency anemia from other types of deprivation in such studies *.
A number of population studies have found iron deficiency to be associated with increased intestinal absorption of and blood levels of lead in young children.
The use of iron supplementation in lead poisoning should be reserved for those individuals who are truly iron deficient or who experience long-lasting lead exposure, such as continued residence in lead-exposed housing.
Population studies provide strong evidence of a relationship between severe anemia in pregnant women and adverse pregnancy outcomes, such as low birth weight, premature birth, and maternal mortality.
While iron deficiency can be a major contributory factor to severe anemia, evidence that iron deficiency anemia is a reason for poor pregnancy outcomes is still lacking *.
Sufficient iron is critical to several immune functions, including the development and division of white blood cells, and the generation of free radicals, which are used for killing infectious agents (e.g., bacteria).
Despite the critical functions of iron in the immune response, the relationship between iron deficiency and susceptibility to infection remains controversial *.
Controlled studies are needed to determine the appropriate use of iron supplementation in regions where malaria is common, as well as in the presence of infectious diseases, such as HIV, tuberculosis, and typhoid.