Iron Deficiency Anemia
Iron deficiency anemia is a low red blood cell count or hemoglobin level caused by too little iron in the body. Hemoglobin is an iron-containing molecule in the red blood cells that carries oxygen to cells throughout the body.
What is going on in the body?
Though anemia has many causes, iron deficiency is the most common. Iron is a very important part of the hemoglobin molecule. When the body does not have enough iron stored, too little hemoglobin is made to fill the red blood cells. The size and number of red blood cells decreases, cutting down on the amount of oxygen that the blood can deliver to the tissues.
What are the causes and risks of the condition?
Iron deficiency anemia occurs when iron intake cannot keep pace with iron loss. This can be due to:
blood loss, such as gastrointestinal bleeding or heavy menstrual bleeding
decreased ability to absorb iron from the diet, which can occur with bowel disorders
growth spurts, which increase the body's need for iron
low intake of iron in the diet
pregnancy and breastfeeding, which increase a woman's need for iron
- taking certain medications that interfere with iron absorption from the digestive tract, such as antacids
Women of childbearing age, pregnant women, children, and teens are at higher risk for iron deficiency than others.
What can be done to prevent the condition?
Many cases of iron deficiency anemia can be prevented by eating a diet rich in iron or taking iron supplements. Some of the foods that are high in iron are as follows:
- dried beans and peas
- dried fruit and nuts
- green leafy vegetables
- iron-fortified breads and cereals
- liver and other meats
- poultry and eggs
- whole grains
How is the condition diagnosed?
Though clues to iron deficiency anemia can be obtained from the medical history and physical exam, the condition is diagnosed with a complete blood count (CBC). In iron deficiency, the hemoglobin and hematocrit values will be lower than normal, and the red cells will be smaller than usual and appear pale under the microscope.
Further tests may be needed to determine the reason for the low iron if it is not clear. A simple blood test can measure the body's iron stores. If the iron deficiency is suspected to be a result of long-term blood loss, a rapid chemical test will show if the stool contains blood.
In complex cases, a bone marrow biopsy may be helpful. The biopsy involves inserting a large, hollow-bore needle through the skin into the hipbone or sternum to withdraw a sample of bone marrow. Bone marrow is a soft substance in the middle of some bones. Red blood cells are made in the marrow; for this reason, much of the body's iron is stored here. A sample of bone marrow can help determine the reason for iron deficiency.
Long Term Effects
What are the long-term effects of the condition?
Almost all problems caused by iron deficiency anemia can be reversed with treatment. However, if the anemia is severe enough, or is accompanied by other serious health conditions, it can lead to:
What are the risks to others?
Iron deficiency anemia is not contagious. It poses no risk to others.
What are the treatments for the condition?
The first step in treatment for iron deficiency anemia is to find and correct the reason for low iron levels. For example, the source of blood loss may need to be identified. Iron stores are then replaced. If a person does not have a problem absorbing iron, this can be done through a diet rich in iron or iron supplements. Iron is best absorbed on an empty stomach.
The individual should follow these dietary guidelines to increase iron stores in the body.
- Avoid eating foods rich in calcium at the same time as the iron-rich food or supplement because calcium can reduce the absorption of iron.
- Eat foods rich in iron, as listed in the prevention section above.
- Eat foods rich in vitamin C, which helps the body absorb iron.
Even when the body is healthy, it does not take in iron very well. Because of that, a person may be advised to take iron supplements for several months to a year. Iron should be taken as prescribed by the healthcare professional. If oral iron supplements fail, iron can be given intravenously or through shots into a muscle.
What are the side effects of the treatments?
Iron supplements may cause nausea
, heartburn, or constipation
. Iron poisoning can occur with an overdose of iron pills. When iron is given into a vein or muscle, the healthcare professional will need to monitor the person closely. Taking iron this way can cause:
- an allergic reaction
- local pain
- staining of the skin
What happens after treatment for the condition?
With treatment for iron deficiency anemia, most people can return to normal activities as soon as they desire. Lifelong iron replacement is usually not necessary. The exact treatment and when it may end often depends on the underlying cause as well. For example, some people have colon cancer
that has caused blood loss. This may require intensive treatment with surgery and chemotherapy.
How is the condition monitored?
After treatment for iron deficiency anemia is finished, blood tests are done to make sure that the iron stores have been replenished. Any new or worsening symptoms should be reported to the healthcare professional.
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Duyff, R., MS, RD, CFCS. (1996). The American Dietetic Association's Complete Food&Nutrition Guide. Minnesota: Chronimed Publishing.