Iron deficiency is one of the commonest worldwide nutritional disorders and anemia is a frequent manifestation of its presence. Children and menstruating women are most commonly affected due to their increased iron requirements. The incidence of iron deficiency is greatest in developing countries due to the ingestion of a diet from which iron is poorly bio‐available. Besides anemia, other nonhematological complications of iron deficiency may occur which have uncertain long‐term consequences. While iron supplementation is beneficial in targeted segments of a population, iron fortification of the diet is a preferable method to prevent iron deficiency. A battery of laboratory measurements are necessary for assessing iron status in population studies, and careful long‐term screening is recommended to examine the effects of iron fortification programs.