Iron is a trace mineral needed to make hemoglobin, the protein needed to carry oxygen throughout the body. Hemoglobin gives red blood cells their color, and stores most of the body’s iron supply. Iron is also stored in muscle tissue and this helps supply the muscles with the oxygen needed to make them contract.
Healthy adult men usually get enough iron from the food they eat. Men have enough reserves of iron in their bodies to last for several years, even if they take in no new iron. Therefore, men rarely develop an iron deficiency.
Women, however, can lose large amounts of iron because of menstrual bleeding, during pregnancy, or while breast-feeding. Therefore, women are more likely than men to develop an iron deficiency and may need to take an iron supplement. Iron deficiency in men and women past menopause usually is related to abnormal bleeding such as from stomach ulcers or colon cancer.
Good sources of dietary iron include meat, fish, poultry, lentils, beans, leaf vegetables, tofu, chickpeas, black-eyed pea, strawberries and farina.
Iron provided by dietary supplements is often found as Iron (II) fumarate. Iron sulfate is as well absorbed, and less expensive. The most bioavailable form of iron supplement (ten to fifteen times more bioavailable than any other) is iron amino acid chelate. The RDA for iron varies considerably based on the age, gender, and source of dietary iron (heme-based iron has higher bioavailability).
However, too much ingested iron can damage the cells of the gastrointestinal tract directly and may enter the bloodstream by damaging the cells that would otherwise regulate its entry. Once there, it causes damage to cells in the heart, liver and elsewhere. This can cause serious problems, including the potential of death from overdose, and long-term organ damage in survivors.