Anemia is a blood problem. It can be either not having enough red blood cells (RBCs), or not having enough hemoglobin (the part of red blood cells that carries oxygen).
If you donâ€™t have enough red blood cells, have too little hemoglobin, or your hemoglobin is not working properly, you canâ€™t get enough oxygen to your cells. Your cells need oxygen work properly.
What is the cause?
There are different causes for different types of anemia.
Iron deficiency anemia
This is the most common form of anemia. It happens when there is not enough iron in your blood. Your blood cells need iron to make hemoglobin. Iron deficiency anemia may happen when there is not enough iron in your diet. It may also happen if you lose a lot of blood. For example, women lose blood during their menstrual periods. Another cause of blood loss may be internal bleeding in the stomach or in the intestine. Pregnant women may have anemia because the baby uses iron to make red blood cells and to grow.
This kind of anemia happens when red blood cells are destroyed or damaged by infection, drugs, or certain problems you are born with.
Vitamin B12 deficiency anemia
This type of anemia most often happens when your intestines have trouble absorbing vitamin B12. Stomach or intestinal illness, some medicines, and some problems you are born with can keep your body from absorbing vitamin B12. Some vegetarians may not get enough B12 from the foods they eat. Your body needs vitamin B12 to make healthy red blood cells.
Folic acid deficiency anemia
Folic acid, also called folate, is another kind of B vitamin. Your body needs folic acid to make healthy red blood cells. Folic acid deficiency anemia can happen when you donâ€™t get enough folic acid in your diet. Not enough folic acid during early pregnancy can cause birth defects, such as spina bifida. This type of anemia is common in:
People who have problems absorbing nutrients from food
People who use certain medicines every day
Anemia caused by problems with red blood cells that you are born with
Sickle cell anemia is caused by abnormal, sickle-shaped red blood cells. The abnormal blood cells are damaged or destroyed as they flow through the bloodstream. The deformed cells may block tiny blood vessels and cause severe pain and other problems. Sickle cell disease is inherited, which means that it is passed from parents to children through their genes. Genes are inside each cell of your body. They contain the information that tells your body how to develop and work. Sickle cell disease is most common among in people whose ancestors came from Africa, Italy, Greece, the Middle East, India, the Caribbean, Central America, or South America.
Thalassemia is an inherited condition in which the red blood cells have less hemoglobin than normal. The cells donâ€™t last as long as normal red blood cells. There are different forms of thalassemia, depending on which genes are affected. Most forms of thalassemia are mild, but some are life threatening for children. Thalassemia is most common in people whose ancestors came from Italy, Greece, Africa, Asia, India, and the South Pacific.
Anemia caused by disease
Some of the long-term (chronic) diseases that may cause anemia are:
Immune system diseases, such as rheumatoid arthritis and lupus
Infections such as HIV/AIDS or hepatitis
What are the symptoms?
Mild anemia usually does not cause symptoms. Different types of anemia may cause different symptoms. For most types of anemia, severe symptoms include:
Feeling unusually weak and tired
Pale skin and gums, or other skin changes such as bruises, yellowing of the skin and eyes, or tiny red spots on the skin
Lightheadedness or fainting, especially when you stand up
Shortness of breath, especially with activity
How is it diagnosed?
Your healthcare provider will ask about your symptoms and medical history and examine you. You will have blood tests to check for possible causes.
How is it treated?
Treatment depends on the type of anemia
To treat iron deficiency anemia, your healthcare provider may prescribe iron supplements or a diet of foods rich in iron. Depending on your age and health, your provider may need to look for causes of blood loss, such as an ulcer or cancer.
Vitamin B12 deficiency anemia may be treated with pills or shots of vitamin B12.
Folic acid deficiency anemia is treated with folic acid or folate tablets.
Some medicines may be used to try to prevent severe symptoms of sickle cell anemia. Severe cases are treated with IV fluids, rest, and pain medicine. If too many red blood cells are destroyed, you may need a blood transfusion.
Treatment of thalassemia depends on how severe it is and your age. Sometimes it needs to be treated with a blood transfusion. People who have thalassemia must not take iron tablets.
Anemia caused by chronic disease may be treated with medicine that helps your body make more red blood cells.
You will have follow-up visits with your provider to check if your treatment is working.
How can I take care of myself?
Follow the full course of treatment prescribed by your healthcare provider. Ask your provider:
How and when you will hear your test results
How long it will take to recover
What activities you should avoid and when you can return to your normal activities
How to take care of yourself at home
What symptoms or problems you should watch for and what to do if you have them
Make sure you know when you should come back for a checkup.
How can I help prevent anemia?
The prevention of anemia depends on the cause. For example:
If your anemia was caused by your diet, eating more foods rich in the missing nutrient will help keep it from coming back.
If your anemia is caused by a chronic disease, treating the disease may help prevent anemia.
If sickle cell anemia or thalassemia run in your family, genetic counseling may help you avoid passing it on to your children.
Developed by RelayHealth.
Adult Advisor 2015.1 published by RelayHealth. Last modified: 2014-05-07 Last reviewed: 2014-05-07
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
National Heart, Lung Blood Institute. What Are the Signs and Symptoms of Iron-Deficiency Anemia? US Dept of Health and Human Services, National Institutes of Health, National Heart, Lung, Blood Institute. 3/2014. Accessed 4/2014 from
PubMedHealth. Pernicious Anemia. US Dept of Health and Human Services, National Institutes of Health, National Library of Medicine, National Center for Biotechnology Information. 2/8/2012. Accessed 4/25/2012 from http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001595/.