Globally, anemia affects more than 1.6 billion people, or approximately 25% of the population. In developing countries, approximately 50% of anemia in the population is thought to be due to iron-deficiency, but the proportion may vary among population groups and in different areas according to local conditions.
Therefore, the WHO estimates that one out of every two preschool children and pregnant women in developing countries are iron deficient. The highest prevalence of anemia is in preschool-age children (47%); however, the population group with the greatest number of anemic individuals is non-pregnant women (468 million). Likewise, the highest proportion of individuals affected is in Africa (48 to 68%), while the greatest number affected is in South-East Asia (315 million). In both instances, the problem is evidently linked to poverty.