Anemia (uh-NEE-me-uh) 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 (HEE-muh-glow-bin). 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 or weak. You also may have other symptoms, such as shortness of breath, dizziness, or headaches.
Severe or long-lasting anemia can damage your heart, brain, and other organs in your body. Very severe anemia may even cause death.
Blood is made up of many parts, including red blood cells, white blood cells, platelets (PLATE-lets), 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 (PLATE-lets) 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.
Anemia has three main causes: blood loss, lack of red blood cell production, or high rates of red blood cell destruction. These causes might be the result of diseases, conditions, or other factors.
Many types of anemia can be mild, short term, and easily treated. You can even prevent some types with a healthy diet. Other types can be treated with dietary supplements.
However, certain types of anemia can be severe, long lasting, and even life threatening if not diagnosed and treated.
If you have signs or symptoms of anemia, see your doctor to find out whether you have the condition. Treatment will depend on the cause of the anemia and how severe it is.
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