What is anemia?


Anemia: Overview

Anemia is a low level of red blood cells, which carry oxygen throughout your body. Many things can cause anemia. Lack of iron is one of the most common causes. Your body needs iron to make hemoglobin. This is a substance in red blood cells that carries oxygen from the lungs to your body's cells. Without enough iron, the body produces fewer and smaller red blood cells. As a result, your body's cells do not get enough oxygen, and you feel tired and weak. And you may have trouble concentrating.

Bleeding is the most common cause of a lack of iron. You may have heavy menstrual bleeding or bleeding caused by conditions such as ulcers or cancer. Regular use of aspirin or other anti-inflammatory medicines (such as ibuprofen) also can cause bleeding in some people. A lack of iron in your diet also can cause anemia, especially at times when the body needs more iron. This includes during pregnancy, infancy, and the teen years.

Your doctor may have prescribed iron pills. It may take several months of treatment for your iron levels to return to normal. Your doctor also may suggest that you eat foods that are rich in iron, such as meat and beans.

There are many other causes of anemia. It is not always due to a lack of iron. Finding the specific cause of your anemia will help your doctor find the right treatment for you.


Anemia is a condition in which a person doesn't have enough red blood cells. With fewer red blood cells, your blood isn't able to carry enough oxygen to the cells in your body. This can cause symptoms such as weakness, skin that is more pale than usual, and general tiredness (fatigue).

Different types of anemia are caused by:

  • Blood loss, such as heavy bleeding during periods or bleeding inside your body from ulcers or another problem.
  • Too many red blood cells being destroyed, such as from a disease (like thalassemia or sickle cell disease) or from cancer treatments (like chemotherapy).
  • Not enough red blood cells being made by your body, such as if what you eat doesn't have enough nutrients, or if you are pregnant, or you have a disease (like chronic kidney disease, diabetes, or cancer).

Each type of anemia is treated differently.

What are the symptoms of anemia?

When you have anemia, you may feel dizzy, tired, and weak. You may also feel your heart pounding or feel short of breath. It may be hard to focus and think clearly.

How is anemia treated?

Sometimes eating more of a variety of healthy foods, taking iron pills, or taking folic acid or vitamin B12 supplements is what's needed. But you may also need medicine or other treatment for any problem that's causing the anemia. And people who are very anemic may need blood transfusions.

How is anemia diagnosed?

A blood test, sometimes done as part of a routine exam, will tell your doctor if you have anemia. Then your doctor will do other tests to figure out what's causing it.

How can you care for yourself when you have anemia?

Your doctor may recommend eating more iron-rich foods. These include red meat, poultry, eggs, beans, raisins, whole-grain bread, and leafy green vegetables. Some fortified cereals and grains are high in iron. You may also need to take iron pills.

What causes anemia?

Some common reasons why you might get anemia include:

  • You lose too much blood. This is a common cause of anemia, especially for those who have heavy bleeding during their periods. It can also happen with ulcers or other problems that cause bleeding inside the body.
  • Your body doesn't make enough red blood cells. This can happen if your food doesn't include enough iron, folic acid, and vitamin B12. It can also happen during pregnancy. Sometimes long-term diseases can keep your body from making enough red blood cells too. Examples include kidney disease, arthritis, diabetes, and cancer.
  • You have a disease or other problem that destroys red blood cells. Examples include sickle cell disease and thalassemia. Some medical treatments, like chemotherapy, can destroy red blood cells as well.

What is anemia?

Having anemia means you don't have enough red blood cells. Your body needs these cells to carry oxygen from your lungs to the rest of your body. Anemia is fairly common. It's often easily treated. Sometimes, though, it's serious.

Anemia: When to call

Call 911 anytime you think you may need emergency care. For example, call if:

  • You have symptoms of a heart attack. These may include:
    • Chest pain or pressure, or a strange feeling in the chest.
    • Sweating.
    • Shortness of breath.
    • Nausea or vomiting.
    • Pain, pressure, or a strange feeling in the back, neck, jaw, or upper belly or in one or both shoulders or arms.
    • Lightheadedness or sudden weakness.
    • A fast or irregular heartbeat.
    After you call 911, the operator may tell you to chew 1 adult-strength or 2 to 4 low-dose aspirin. Wait for an ambulance. Do not try to drive yourself.
  • You passed out (lost consciousness).
  • You have severe shortness of breath.

Call your doctor now or seek immediate medical care if:

  • You have new or increased shortness of breath.
  • You are dizzy or lightheaded, or you feel like you may faint.
  • You have new or worse nausea and vomiting.
  • Your fatigue and weakness continue or get worse.
  • You have any abnormal bleeding, such as:
    • Nosebleeds.
    • Vaginal bleeding that is different (heavier, more frequent, at a different time of the month) than what you are used to.
    • Bloody or black stools, or rectal bleeding.
    • Bloody or pink urine.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You do not get better as expected.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.