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Iron Deficiency Anemia
What is iron deficiency anemia?
Iron deficiency anemia means that your body doesn't have enough iron to make red blood cells.
Iron is important because it helps you get enough oxygen throughout your body. Your body uses iron to make hemoglobin. This is a part of your red blood cells. Hemoglobin carries oxygen through your body. If you don't have enough iron, your body makes fewer and smaller red blood cells. Then your body has less hemoglobin, and you can't get enough oxygen.
Iron deficiency is the most common cause of anemia.
What causes it?
Iron deficiency anemia is caused by low levels of iron in the body. Many things can cause low iron levels. These include heavy menstrual bleeding, not getting enough iron in food, and health problems that cause bleeding inside your body or make it hard to absorb iron.
What are the symptoms?
You may not notice the symptoms of iron deficiency anemia. That's because it develops slowly, and the symptoms may be mild. As anemia gets worse, you may feel weak and tired or dizzy. You may get headaches, feel short of breath, and have trouble concentrating.
How is it diagnosed?
To diagnose iron deficiency anemia, your doctor will do a physical exam and ask about your health and symptoms. Your doctor will also do blood tests. These tests may include a complete blood count to look at your red blood cells and an iron test that shows how much iron is in your blood.
How is iron deficiency anemia treated?
To treat iron deficiency anemia, your doctor will try to find the cause of the anemia and treat that problem. Your doctor can recommend ways to increase your iron levels, such as taking iron supplement pills and eating iron-rich foods. Talk to your doctor before taking iron pills.
How can you prevent it?
You can help prevent iron deficiency anemia by eating iron-rich foods every day. These include meats, vegetables, and whole grains. To help prevent anemia in babies and children, follow recommendations for feeding infants. Make sure that babies and children get enough iron. If you're pregnant, you can take prenatal vitamins that include iron.
Iron deficiency anemia is caused by low levels of iron in the body. You might have low iron levels from:
- Blood loss, such as:
- Not getting enough iron in food. This can happen in people who need a lot of iron, such as small children, teens, and pregnant women.
- Not absorbing iron well in your body. This problem may occur if you have celiac disease or if you've had part of your stomach or small intestine removed.
Your body needs iron to make hemoglobin. Hemoglobin is a substance in red blood cells that carries oxygen from the lungs to cells all through your body. If you do not get enough iron, your body makes fewer and smaller red blood cells. As a result, your body's cells may not get enough oxygen.
Adult men need 8 milligrams of iron a day; adult women need 18 milligrams of iron a day. After menopause, women need 8 milligrams of iron a day. A pregnant woman needs 27 milligrams of iron a day. Infants and young children have higher iron needs relative to their size than other age groups. People who have lost blood because of ulcers or heavy menstrual periods may become very low in iron and may develop anemia.
Most people can get the iron their bodies need by eating enough of certain iron-rich foods. Your doctor may recommend that you take an iron supplement along with eating an iron-rich diet.
Iron deficiency anemia develops slowly, and the symptoms may be mild. Mild anemia may not cause noticeable symptoms. If anemia is severe, symptoms may include:
- Feeling weak and tired more easily.
- Feeling short of breath during exercise.
- Trouble concentrating.
- Being grumpy or cranky.
- Feeling dizzy.
- Pale skin.
- Craving substances that aren't food (pica). In particular, a craving for ice can be a sign of iron deficiency anemia.
Other signs may include:
- Rapid heartbeat.
- Brittle fingernails and toenails.
- Cracked lips.
- Smooth, sore tongue.
- Muscle pain during exercise.
- Trouble swallowing.
Babies and small children who have anemia may:
- Be fussy.
- Have a short attention span.
- Grow more slowly than normal.
- Develop certain skills, such as walking and talking, later than normal.
Iron deficiency anemia develops slowly, and the symptoms may be mild. As anemia gets worse, you may feel weak and tired or dizzy. Or you may get headaches. Your doctor will try to find the cause of the anemia and treat that problem. Most people start to feel better after treatment begins.
Exams and Tests
Your doctor will do a physical exam and ask about your symptoms and past health. Your doctor may ask about:
- Any medicines that you take.
- Your eating habits.
- Any current or past conditions or diseases that you or a close family member has had.
- Your history of pregnancy, menstruation, or other sources of bleeding.
Your doctor will recommend tests to check for low iron levels and anemia. They can help find the cause of anemia. Tests include:
- A complete blood count (CBC). This looks at the shape, color, number, and size of your blood cells.
- Iron tests. This measures the amount of iron in your blood. It can help find the type and severity of anemia.
- Reticulocyte count. This measures how well your body can make new blood cells.
- A ferritin level test. This shows how much iron may be stored in the body. Abnormally low ferritin levels may point to iron deficiency anemia.
To treat iron deficiency anemia, your doctor will look for the cause of the anemia and treat that problem. Your doctor can recommend ways to increase your iron levels, such as taking iron supplement pills and eating iron-rich foods.
Most people start to feel better after a few days of taking iron pills. But don't stop taking them, even if you feel better. You'll need to keep taking the pills for several months to build up the iron in your body.
If you think you have anemia, don't try to treat yourself. Don't take iron pills on your own without seeing your doctor first. If you do, the pills may cause you to have too much iron in your blood, or even iron poisoning.
You may need to get iron through an IV if you have problems with the iron pills. If your anemia is severe, your doctor may give you a blood transfusion.
If you have iron deficiency anemia, your doctor may suggest taking iron supplement pills. Taking iron pills and getting enough iron in your food will correct most cases of iron deficiency anemia.
Here are some things you need to know when treating this condition.
- Do not take iron pills without checking with your doctor.
If you think you have anemia, see your doctor. Do not try to treat yourself.
- Taking iron pills could delay the diagnosis of a serious problem, such as a bleeding ulcer or colon cancer.
- If the anemia is not caused by iron deficiency, taking iron pills won't relieve the anemia. And it may cause you to have too much iron in your blood, or even iron poisoning.
- Take iron pills for as long as your doctor tells you to.
You may feel better after a few days of taking iron pills. But don't stop taking the pills. You'll need to keep taking them for several months to build up your iron stores.
- Eat iron-rich foods each day.
Iron-rich foods include meats, vegetables, and whole grains such as iron-fortified cereals.
- Get the most benefit from your iron pills and food.
- Take vitamin C (ascorbic acid) or drink orange juice with your pills. Vitamin C helps your body absorb more iron.
- Steam vegetables to help them keep their iron content.
- Take iron on an empty stomach, if you can.
Iron is absorbed best if you take it on an empty stomach. But in some people, iron supplements can cause problems such as stomach discomfort and constipation.
- If you're having stomach problems, you may need to take the pills with food.
- If your iron pills make you feel too sick, talk to your doctor. There may be another type of iron pill you can take.
- Do not take iron pills with certain substances.
- Don't take your iron pills within 2 hours of taking antacids or tetracycline.
- Don't take your iron pills with:
- Tea, coffee, chocolate, and other food or beverages high in caffeine.
- Milk and other calcium-rich foods or supplements.
- High-fiber foods, such as bran, whole grains, nuts, and raw green vegetables.
- Keep iron pills out of the reach of children.
Iron poisoning can be very dangerous.
Current as of: November 29, 2021
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Kathleen Romito MD - Family Medicine
Caroline S. Rhoads MD - Internal Medicine
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