Definition

Anemia is a condition characterized by abnormally low levels of red blood cells.

Description

Cells require a constant supply of oxygen in order to stay healthy. Oxygen is delivered to cells by red blood cells, which pick up oxygen in the lungs. They carry the oxygen to cells through the bloodstream.

The oxygen-carrying molecule in red blood cells is hemoglobin (pronounced HEE-muh-glo-bin). Hemoglobin is a large, complex molecule. It contains an atom of iron at its center. Iron attaches itself easily to oxygen atoms. It is the iron in hemoglobin that actually carries oxygen to cells.

Anemia develops when the body has an insufficient supply of red blood cells and hemoglobin. When that happens, cells do not get the oxygen they need and begin to die off. A variety of medical problems may develop.

Types of Anemia

More than four hundred different kinds of anemia have been...