Iron deficiency anemia is a decrease in the red cells of the blood caused by too little iron. (See also Iron-deficiency anemia - children. )

Alternative Names

Anemia - iron deficiency

Causes, incidence, and risk factors

Iron deficiency anemia is the most common form of anemia . Approximately 20% of women, 50% of pregnant women, and 3% of men are iron deficient. Iron is an essential component of hemoglobin , the oxygen carrying pigment in the blood. Iron is normally obtained through the food in the diet and by the recycling of iron from old red blood cells. The causes of iron deficiency are too little iron in the diet, poor absorption of iron by the body, and loss of blood (including from heavy menstrual bleeding ). It can also be related to lead poisoning in children. Anemia develops slowly after the normal stores of iron have been depleted in the body and in the bone marrow. Women, in general, have smaller stores of iron than men and have increased loss through menstruation, placing them at higher risk for anemia than men. In men and postmenopausal women, anemia is usually due to gastrointestinal blood loss associated with ulcers , the use of aspirin or nonsteroidal anti-inflammatory medications (NSAIDS), or colon cancer. High-risk groups include: women of child-bearing age who have blood loss through menstruation; pregnant or lactating women who have an increased requirement for iron; infants, children, and adolescents in rapid growth phases; and people with a poor dietary intake of iron through a diet of little or no meat or eggs for several years. Risk factors related to blood loss are peptic ulcer disease , long term aspirin use, or colon cancer .

Signs and tests

Treatment

Identification of the cause of the deficiency is essential, particularly in older patients who are most susceptible to intestinal cancer. Oral iron supplements are in the form of ferrous sulfate. The best absorption of iron is on an empty stomach, but many people are unable to tolerate this and may need to take it with food. Milk and antacids may interfere with absorption of iron and should not be taken at the same time as iron supplements. Vitamin C can increase absorption and is essential in the production of hemoglobin . Supplemental iron is needed during pregnancy and lactation because normal dietary intake rarely supply the required amount. The hematocrit should return to normal after 2 months of iron therapy, but the iron should be continued for another 6 to 12 months to replenish the body's iron stores, contained mostly in the bone marrow. Intravenous or intra-muscular iron is available for patients when iron taken orally is not tolerated. Iron-rich foods include raisins, meats (liver is the highest source), fish, poultry, eggs (yolk), legumes (peas and beans), and whole grain bread.

Expectations (prognosis)

With treatment, the outcome is likely to be good. In most cases the blood counts will return to normal in 2 months.

Complications

There are usually no complications. However, iron deficiency anemia may recur, so regular follow-up is encouraged. Children with this disorder may have an increased susceptibility to infection.

Calling your health care provider

Call for an appointment with the health care provider if symptoms develop.

Prevention

Dietary sources of iron are red meat, liver, and egg yolks. Flour, bread, and some cereals are fortified with iron. If the diet is deficient in iron, iron should be taken orally. During periods of increased requirements such as pregnancy and lactation, increase dietary intake or take iron supplements.