Anemia afflicts an estimated two billion people worldwide, mostly due to iron deficiency.
It primarily affects women. Yet among adolescents, prevalence rates of anemia are closer for males and females in some parts of the world. The prevalence of anemia is disproportionately high in developing countries, due to poverty, inadequate diet, certain diseases, pregnancy and lactation, and poor access to health services. Young people are particularly susceptible because of their rapid growth and associated high iron requirements. Anemia is a critical health concern because it affects growth and energy levels.