Anemia is a lack of iron in the blood that can make you feel tired and drained of energy. Anemia is linked to a problem with hemoglobin, a protein in the red blood cells that is rich in iron. Hemoglobin helps to carry oxygen to different areas of the body. When you have a reduced number of red blood cells or these cells do not contain enough hemoglobin, less oxygen is in the blood that is distributed throughout your body. This causes the tiredness associated with anemia.

There are different types of anemia, which have different causes. Often anemia can occur when there is blood loss, as during a trauma or during surgery. Other conditions are inherited or develop over time.

In more severe cases of anemia, the body cannot produce enough red blood cells, as in aplastic anemia, or there is an excessive amount of red blood cell destruction, as in hemolytic anemia. These severe types of anemia require medical attention and often treatments such as blood transfusions. Mild to moderate cases of anemia can be prevented or treated with food and are often referred to as iron-deficiency anemia.