Iron deficiency is the most common cause of anemia (low red blood cell count) worldwide.
Iron deficiency affects about 10 percent of pre-menopausal women, 6 percent of post-menopausal women, and fewer than 2 percent of men.
Most older people who become deficient do so not because they consume too little iron but because of chronic internal bleeding usually caused by ulcers, polyps, or tumors. Three groups of people face an increased risk of iron deficiency, even without internal bleeding. These are:
- People who have lost their teeth. Those people should take a multi-vitamin and mineral supplement containing iron if they have difficulty eating a balanced diet.
- Women who menstruate heavily. Some of those women may also need supplements to replace iron - but they should first make sure that menstruation is the sole cause of their anemia. Other premenopausal women can easily get enough iron by eating a moderate amount of meat. Even strict vegetarians can get all the iron they need by including certain iron-rich plant foods in their diet, such as legumes, dark green leafy vegetables, and fortified breads and cereals.
- Pregnant women. They should take a daily supplement containing iron to provide the extra iron needed to nourish the developing fetus.
Severe iron deficiency (uncommon in the U.S.) causes progressive skin and mucosal changes. These include a smooth tongue and brittle nails.
Many iron-deficient patients develop pica, an unusual craving for specific foods (ice cubes, lettuce, etc.) often not rich in iron.
Because iron is necessary for the production of hemoglobin, the measurement of iron may be helpful in evaluating anemia. The most commonly used blood tests are serum iron, total iron-binding capacity (TIBC), and serum ferritin.
To make the diagnosis of iron deficiency anemia, one can either demonstrate an iron-deficient state or evaluate the response to a therapeutic trial of iron replacement. Since the anemia is seldom life-threatening, the most important part of treatment is identification of the cause, especially any source of blood loss.
There is no better treatment than ferrous sulfate, 325 mg three times daily, which provides 180 mg of iron daily of which 10mg is usually absorbed. Patients who cannot tolerate iron on an empty stomach should take it with food.
Use of parenteral (intravenous) iron is indicated where there is intolerance to oral iron, poor absorption, gastrointestinal disease precluding the use of oral iron, continued blood loss, and replacement of depleted iron stores when oral iron fails.