Iron What does it do? Iron is part of hemoglobin, the oxygen-carrying component of the blood. Iron-deficient people tire easily, because their bodies are starved for oxygen. Iron is also part of myoglobin, which helps muscle cells store oxygen. Without enough iron, ATP (the fuel the body runs on) cannot be properly synthesized. As a result, some iron-deficient people become fatigued even when their hemoglobin levels are normal.
Although iron is part of the antioxidant enzyme catalase, iron is not generally considered an antioxidant, because too much iron can cause oxidative damage.
Where is it found? The most absorbable form of iron, called “heme” iron, is found in oysters, meat, poultry, and fish. Non-heme iron is also found in these foods, as well as in dried fruit, molasses, leafy green vegetables, and wine. Acidic foods (such as tomato sauce) cooked in an iron pan can also be a source of dietary iron.
In what conditions might iron be supportive?
If iron deficiency is the cause of the following health concerns, then iron may be helpful.
• athlete’s foot • HIV support • iron deficiency anemia
Who is likely to be deficient? Vegetarians eat less iron than non-vegetarians, and the iron they eat is somewhat less absorbable. As a result, vegetarians are more likely to have reduced iron stores.1 However, iron deficiency is not usually caused by a lack of iron in the diet alone; there’s often an underlying cause, such as iron loss in menstrual blood.
Pregnant women, marathon runners, people who take aspirin, and those who have parasitic infections, hemorrhoids, ulcers, ulcerative colitis, Crohn’s disease, or other conditions that cause blood loss or malabsorption are likely to become deficient.
Individuals who fit into one of these groups, even pregnant women, shouldn’t automatically take iron supplements. Fatigue, the first symptom of iron deficiency, can be caused by many other things. A nutritionally oriented doctor should assess the need for iron supplements, since taking iron when it isn’t needed does no good and may do some harm.
How much should I take? If a nutritionally oriented doctor diagnoses iron deficiency, iron supplementation is essential. A common adult dose is 100 mg per day. When iron deficiency is diagnosed, the doctor must also determine the cause. Usually it’s not serious (such as normal menstrual blood loss or blood donation). Occasionally, however, iron deficiency signals ulcers or even colon cancer.
Many premenopausal women become marginally iron deficient unless they supplement with iron. Even so, the 18 mg of iron present in most multiple-vitamin/mineral supplements is often adequate.
Are there any side effects or interactions? Huge overdoses (as when a child swallows an entire bottle of iron supplements) can be fatal. Keep iron-containing supplements out of a child’s reach. Hemochromatosis, hemosiderosis, polycythemia, and iron-loading anemias (such as thalassemia and sickle cell anemia) are conditions involving excessive storage of iron. Supplementing iron can be quite dangerous for people with these diseases.
Supplemental doses required to overcome iron deficiency can cause constipation. Sometimes switching the form of iron, getting more exercise, or treating the constipation with fiber and fluids is helpful. Sometimes it’s necessary to reduce the amount of iron if constipation occurs.
Some researchers have potentially linked excess iron to diabetes,2 cancer,3 increased risk of infection,4 lupus erythematosus (SLE),5 and exacerbation of rheumatoid arthritis.6 While none of these links has been proven, it is known that too much iron causes free radical damage, which can cause or exacerbate most of these diseases. People who are not iron deficient should not supplement iron when potential risks might exist and no benefit can be found.
Caffeine, high-fiber foods, and calcium supplements reduce iron absorption. Vitamin C slightly increases iron absorption.7 Taking vitamin A with iron helps treat iron deficiency, since vitamin A helps the body use iron stored in the liver.8 9
References:
1. Sullivan JL. Stored iron and ischemic heart disease. Circulation 1992;86:1036 [editorial].
2. Cutler P. Deferoxamine therapy in high-ferritin diabetes. Diabetes 1989;38:1207-10.
3. Stevens RG, Graubard BI, Micozzi MS, et al. Moderate elevation of body iron level and increased risk of cancer occurrence and death. Int J Cancer 1994;56:364-9.
4. Weinberg ED. Iron withholding: a defense against infection and neoplasia. Am J Physiol 1984;64:65-102.
5. Oh VMS. Iron dextran and systemic lupus erythematosus. BMJ 1992;305:1000 [letter].
6. Dabbagh AJ, Trenam CW, Morris CJ, Blake DR. Iron in joint inflammation. Ann Rheum Dis 1993;52:67-73.
7. Hunt JR, Gallagher SK, Johnson LK. Effect of ascorbic acid on apparent iron absorption by women with low iron stores. Am J Clin Nutr 1994;59:1381-5.
8. Suharno D, West CE, Muhilal, et al. Supplementation with vitamin A and iron for nutritional anemia in pregnant women in West Java, Indonesia. Lancet 1993;342:1325-8.
9. Semba RD, Muhilal, West KP Jr, et al. Impact of vitamin A supplementation on hematological indicators of iron metabolism and protein status in children. Nutr Res 1992;12:469-78.
Copyright © 1998 Virtual Health, LLC
It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over-the-counter medication is also available. Consult your physician, nutritionally-oriented health care practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.The information presented in HealthNotes Online is for informational purposes only.