Anemia Health Center

Anemia is a condition in which your blood has a lower than normal number of red blood cells. Anemia also can occur if your red blood cells don't contain enough hemoglobin. Hemoglobin is an iron-rich protein that gives blood its red color. This protein helps red blood cells carry oxygen from the lungs to the rest of the body.

If you have anemia, your body doesn't get enough oxygen-rich blood. As a result, you may feel tired and have other symptoms. Severe or long-lasting anemia can damage the heart, brain, and other organs of the body. Very severe anemia may even cause death.

Blood is made up of various parts, including red blood cells, white blood cells, platelets, and plasma (the fluid portion of blood). Red blood cells are disc-shaped and look like doughnuts without holes in the center. They carry oxygen and remove carbon dioxide (a waste product) from your body. These cells are made in the bone marrow—a sponge-like tissue inside the bones.

White blood cells and platelets also are made in the bone marrow. White blood cells help fight infection. Platelets stick together to seal small cuts or breaks on the blood vessel walls and stop bleeding. With some types of anemia, you may have low numbers of all three types of blood cells.