What Is Anemia?

Anemia (uh-NEE-me-eh) is a condition in which a person’s blood has a lower than normal number of red blood cells (RBCs), or the RBCs don’t have enough hemoglobin (HEE-muh-glow-bin). Hemoglobin—an iron-rich protein that gives the red color to blood—carries oxygen from the lungs to the rest of the body. In people with anemia, the blood does not carry enough oxygen to the rest of the body. As a result, people with anemia feel tired, along with other symptoms, because their bodies are not receiving enough oxygen. In severe or prolonged cases of anemia, the lack of oxygen in the blood can cause serious and sometimes fatal damage to the heart and other organs of the body.

RBCs also are called erythrocytes (eh-RITH-ro-sites). RBCs are disc-shaped and look like doughnuts without a hole in the center. They are produced continually in the spongy marrow inside the large bones of the body and normally last 120 days. RBCs’ main role is to carry oxygen, but they also remove carbon dioxide (a waste product) from cells and carry it to the lungs to be exhaled. White blood cells and platelets are the two other kinds of blood cells. White blood cells help fight infections. Platelets help blood to clot. In some kinds of anemia, there are low amounts of all three types of blood cells.

Outlook

Women and people with chronic diseases are at greater risk for anemia. Many types of anemia can be mild, short-lived, and easily treated. Some forms of anemia can be prevented with a healthy diet, and other forms can be treated with diet supplements.

Certain types of anemia may be severe, long-lasting, and life threatening if not diagnosed and treated. People who have symptoms of anemia should see their doctor to find out if they have the condition, its cause and severity, and how to treat it.

What Causes Anemia?

There are three main causes of anemia: blood loss, lower than normal levels of red blood cell (RBC) production, or higher than normal rates of RBC destruction. More than one of these factors can combine to cause anemia.

Blood Loss

Blood loss is the most common cause of anemia, particularly iron-deficiency anemia. Blood loss can be short term or persist over time. It can be caused by heavy menstrual periods, bleeding in the digestive or urinary tracts, surgery, trauma, or cancer. If bleeding is significant, the body can lose enough RBCs to cause anemia.

Low Levels of RBC Production

Lower than normal levels of RBC production can result from a poor diet that lacks iron, folic acid, or vitamin B12. It also can be caused by conditions that make it difficult for the body to absorb nutrients into the blood.

Chronic diseases like kidney disease and cancer can decrease the body’s ability to produce enough RBCs. Infections, medicines, or radiation used to treat another disease or condition may damage the bone marrow, making it unable to produce RBCs fast enough to replace those that die or are destroyed.

During pregnancy, the fetus needs additional blood cells to develop. The mother may not be able to produce enough RBCs for herself and the fetus, which can result in anemia.

High Rates of RBC Destruction

Higher than normal rates of RBC destruction can be the result of inherited blood disorders like sickle cell anemia, thalassemia, and certain enzyme deficiencies. These disorders create abnormalities in the RBCs that cause them to die off in a shorter period of time than healthy RBCs. In people with hemolytic anemia, the immune system mistakenly attacks RBCs. This destroys the RBCs faster than the body can replace them.

• Anemia is a condition in which a person’s blood has a lower than normal number of red blood cells (RBCs), or the RBCs don’t have enough hemoglobin. Without enough RBCs or hemoglobin, the blood does not carry enough oxygen to the rest of the body.

• Anemia is caused by blood loss, lower than normal levels of RBC production, or higher than normal rates of RBC destruction.

• The lack of oxygen causes people with anemia to feel tired and weak. Other symptoms of anemia include shortness of breath, dizziness, fast or irregular heartbeat, headache, coldness in the limbs, pale or yellow skin, and chest pain.

• Anemia is a common condition affecting more than 3 million people in the United States. Women and people with chronic diseases are at greater risk for anemia. People who have symptoms of anemia should see their doctor to diagnose its cause and severity and to develop an effective treatment plan.

• Anemia is diagnosed using a person’s medical and family history, a physical exam, and tests. A complete blood count often is used to confirm a diagnosis of anemia. Additional tests may be needed to determine the cause and severity of anemia so that an effective treatment can be prescribed.

• Anemia can often be treated and/or controlled. Treatment may lead to benefits such as increased energy and activity levels, improved quality of life, and longer life.

• Some types of anemia may be severe, long lasting, and life threatening if not diagnosed and treated. The lack of oxygen in the body can damage organs. Anemia can harm the heart, which works harder to make up for the lack of blood cells or hemoglobin.

• Many types of anemia can be treated effectively with diet supplements that increase the level of iron and its absorption into the blood.

• Some forms of anemia can be prevented by a healthy diet rich in the vitamins and minerals, especially iron, that are needed to produce RBCs and hemoglobin.

• Some types of anemia are inherited and can’t be prevented. If you have a form of hereditary anemia, it is important that you discuss your personal and family history with your doctor so that timely treatment can begin.