Iron

Iron performs many tasks in the human body. It delivers oxygen from the lungs to all parts of your body, helps your muscles work, and helps break down substances that can damage your body. Hemoglobin is the protein that carries iron and oxygen to all parts of your body. If your cells do not get enough iron, you can get anemia. There are several types of anemia, and the one associated with iron is called iron-deficient anemia. The most common symptoms of anemia are weakness and tiredness. Those at the highest risk of anemia are growing children (6 months to 4 years of age), adolescents (especially girls), and pregnant women.

Uses

The most important use of iron supplements is to improve the symptoms of iron-deficient anemia. This kind of anemia can be caused by prolonged blood loss such as that from a bleeding ulcer or a malignant tumor; iron-poor diet or inefficient absorption of dietary iron; pregnancy; and the rapid growth that takes place during infancy, early childhood, and adolescence.

Dietary Sources

The best dietary sources of iron are liver, lean red meat, poultry, fish, oysters, shellfish, and kidney. Iron from these sources is readily absorbed.

The following foods are also sources of iron: dried beans, fruits, and vegetables. Absorption of iron from these sources depends on other components of the diet. Vitamin C and meat products help iron absorption, while calcium (including all dairy products), bran, tea, and unprocessed whole grain products block absorption.

Iron is often added to these foods: egg yolks, dried fruits, dark molasses, whole-grain and enriched bread, wines, and cereals.

Other Forms

Ferrous sulfate is the most common form of oral iron supplement. Other available include ferrous fumarate, ferrous succinate, ferrous gluconate, ferrous lactate, ferrous glutamate, and ferrous glycine. Slow-release preparations are also available. Supplemental iron should be taken only under the supervision of your health care provider. He or she will recommend the form that is best for you.

How to Take It

For treatment of iron-deficient anemia, adults should take 65 mg of an iron supplement three times a day with water. It is preferable to take the supplements between meals because they are absorbed better without food. As with all medications and supplements, check with a health care provider before giving iron supplements to a child.

Precautions

Iron supplements must be kept in childproof bottles and out of the reach of children. If a child accidentally ingests iron supplements, it can be fatal.

Possible Interactions

The cholesterol-lowering medications cholestyramine and colestipol as well as the antibiotic tetracycline inhibit the absorption of iron. The absorption of iron is also decreased when taking medications such as omeprazole, lansoprazole, ranitidine, cimetidine, or antacids that are often prescribed for the treatment of ulcers or other stomach problems.

Iron inhibits the absorption of oral quinolones (a class of antibiotics that includes ciprofloxacin, norfloxacin, ofloxacin, monifloxacin, and levofloxacin). Iron also decreases the absorption of ACE inhibitors (such as captopril, enalapril, and lisinopril), a class of medications used for the treatment of high blood pressure.

Levodopa, a medication used for the treatment of Parkinson's disease, may decrease iron levels.

Iron may decrease the effectiveness of levothyroxine, a thyroid replacement hormone used to treat an underactive thyroid.

Iron supplements should not be taken at the same time as any of the medications above. It is best to take iron supplements at least two hours before or after taking any of these medications.

Supporting Research

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