What Is Anemia?

Anemia (say: uh-NEE-mee-uh) happens when a person doesn't have the normal amount of red blood cells or if the person is low on hemoglobin (say: HEE-muh-glow-bin). Hemoglobin, a protein, is an important part of red blood cells because it gives the oxygen something to stick to.

Red blood cells (or RBCs, for short) are made inside the bones in the soft, spongy area called the bone marrow (say: MARE-oh). So every time you take a breath, you breathe in oxygen. And your red blood cells carry oxygen to every cell in your body.

What Are the Signs of Anemia?

Some kids with anemia don't know they have it because they don't have any symptoms. A kid who does have symptoms might:

  • look pale
  • seem moody
  • feel dizzy
  • have a fast heartbeat
  • have skin and eyes that look yellow and dark tea-colored pee

If anemia gets worse, a kid who was once very active may become worn out quickly. He or she may feel weak or tired.

Why Do Kids Get Anemia?

A person may get anemia if:

  • not enough red blood cells are made
  • too many red blood cells are destroyed
  • too many red blood cells are lost (from bleeding)

Not enough being made: There are several reasons why the body might not make enough RBCs, but often it's because the person isn't getting enough iron. Iron is a nutrient found in meat, dried beans, and green leafy vegetables. Without iron, the body can't make hemoglobin, the oxygen-carrying part of a red blood cell.

Anemia also can develop if the bone marrow is not working properly. This might be because of an infection or an illness, such as kidney disease. Some medicines, like chemotherapy for cancer, can keep the bone marrow from being able to make enough RBCs.

Too many being destroyed: If the life of a red blood cell is cut short for any reason, the bone marrow may not be able to keep up with the increased demand for new ones. One reason RBCs get destroyed is because their shape changes. Red blood cells should be round and flat like discs. That's a good shape for moving through tight spaces as blood circulates around the body. But if the shape changes, as in sickle cell disease, the red blood cells can stuck and break more easily.

In other cases, the body's own immune system can destroy red blood cells. Some medicines, infections, and diseases also may cause anemia.

Too much lost: When you lose a little blood, like when you cut yourself or have a nosebleed, your bone marrow can make more blood so you don't develop anemia. But if you lose a lot of blood, which may happen in a serious accident, your bone marrow might not be able to replace the red blood cells quickly enough.

Losing a little blood over a long period of time also can lead to anemia. A person might lose more iron from the blood loss than is taken into the body during meals. Without enough iron in the body, the bone marrow can't make enough red blood cells. This can happen in girls who have heavy menstrual periods, especially if they don't get enough iron in their diets, or in people who have inflammatory bowel disease (IBD).

What Do Doctors Do?

When you see the doctor, he or she will examine you and ask questions about how you have been feeling, what you eat, and if you are taking any medicines. If a doctor thinks a kid has anemia, he or she can order a simple blood test called a complete blood count.

The blood sample is checked in a lab. Its red blood cells are counted, the amount of hemoglobin is measured, and the size and shape of the cells are checked. A doctor may order other tests, depending on what he or she thinks is the problem.

How Is Anemia Treated?

Treatment for anemia depends on the cause. In kids, the most common cause of anemia is not getting enough iron in their diets. Some kids may need to take medicine with iron to help their bodies make more red blood cells. It is also important to eat more foods that are rich in iron, like meat, enriched grains and cereals, dried beans, and tofu.

Anemia caused by an infection usually will go away when the infection is treated and the body gets healthy again. For some other types of anemia, the kid may need to see a specialist and have other tests before treatment can start.

Whatever the cause, a person with severe anemia may need a blood transfusion. A transfusion means that donated blood, which is stored at a place called a blood bank, is given through a tube placed into a vein. This may sound a little scary, but millions of kids and adults have blood transfusions every year. Getting a blood transfusion is the fastest way to get blood to deliver oxygen to all the cells in the body.

Kids who have anemia may have to take it easy for a while. But once their bodies start making enough red blood cells, oxygen can reach all their tissues again, and they'll get some of that kid energy back!

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