There are several different classifications of anemia, depending on the underlying pathophysiology (Mansen and McCance, 843). Iron deficiency anemia (IDA) is the most common type of anemia encountered, both in underdeveloped and in developed countries, and is due to a decrease in the number of red cells because of a lack of sufficient iron (MedlinePlus, 2005). Iron is an essential component in the production of hemoglobin, the oxygen-carrying pigment in erythrocytes and is normally obtained in the diet (Mansen and McCance, 2002, 850; MedlinePlus, 2003). Babies are born with roughly 500 mg of iron in their blood, and by adulthood, need to have accumulated roughly 5,000 mg. To keep up with their growing needs, children need to absorb about 1 mg of iron daily, but because they tend to absorb only about 10 percent of the iron they eat, they need to need to ingest 8 to 10 mg of iron each day. Babies who are breastfeeding absorb iron three times better from breast milk than from other foods. However, drinking too much cow's milk can lead to iron deficiency in children because the calcium in the milk competes with iron for absorption.
Iron is needdd in the body for erythropoiesis - the production of new erythrocytes - whose lifespan is roughly 120 days (Mansen and McCance, 850). This necessitates a constant supply of iron, but iron is recycled in the body from dead erythrocytes, keeping total body levels fairly constant. Iron loss from the body in significant amounts is usually through blood loss. Males lose iron in sloughed epithelium, in secretions from the skin and the lining of the gut, and a small amount daily from the gastrointestinal tract, bringing the total loss to about one mg per day (Conrad, 2004). Females lose roughly 500 mg iron with each pregnancy, and through menstruation, varying from four to 100 mg iron per period. Thus women need to take in much more iron than men to keep adequate levels in their bodies. ...