Iron

What does iron do?
Iron is part of hemoglobin, the oxygen-carrying component of the blood. Iron-deficient people tire easily in part 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 (i.e., when they are not anemic).
Although iron is part of the antioxidant enzyme catalase, iron is not generally considered an antioxidant, because too much iron can cause oxidative damage.

Iron may be of benefit relative to the following conditions:

Athletic performance (for treatment of iron-deficiency only)
Childhood intelligence (for deficiency)
Depression (for deficiency)
Iron-deficiency anemia
Menorrhagia (heavy menstruation) (for treatment of iron- deficiency only)
Breast-feeding support
Canker sores
Celiac disease (for treatment of iron-deficiency only)
Pre- and post-surgery health (if deficient or for major surgery)
Pregnancy and Postpartum support (with medical supervision)
Restless legs syndrome (only if iron- deficiency)
Alzheimer's disease (in combination with Co-Enzyme Q10 and vitamin B6)
Dermatitis Herpetiformis
HIV support
Infertility (female) (for treatment of iron-deficiency only)

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.  However, iron deficiency is not usually caused by a lack of iron in the diet alone. An underlying cause, such as iron loss in menstrual blood, often exists.
Pregnant women, marathon runners, people who take aspirin, and those who have parasitic infections, hemorrhoids, ulcers, ulcerative colitis, Crohn's disease, gastrointestinal cancers, or other conditions that cause blood loss or mal-absorption are likely to become deficient.
Infants living in inner city areas may be at increased risk of iron-deficiency anemia and suffer more often from developmental delays as a result.  Supplementation of infant formula with iron up to 18 months of age in inner city infants has been shown to prevent iron-deficiency anemia and to reduce the decline in mental development seen in such infants in some studies.
Breath-holding spells are a common problem affecting about 27% of healthy children. These spells have been associated with iron-deficiency anemia, and several studies have reported improvement of breath-holding spells with iron supplementation.

Iron Supplements
All iron supplements are not the same. Ferrous iron (e.g. ferrous sulfate) is much better absorbed than ferric iron (e.g. ferric citrate). The most common form of iron supplement is ferrous sulfate, but it is known to produce intestinal side effects (such as constipation, nausea, and bloating) in many users. Some forms of ferrous sulfate are enteric-coated to delay tablet dissolving and prevent some side effects, but enteric-coated iron may not absorb as well as iron from standard supplements.

How much is usually taken?
If a doctor diagnoses iron deficiency, iron supplementation is essential. To treat iron deficiency, a common recommended amount for an adult is 100 mg per day; that amount is usually reduced after the deficiency is corrected. 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.
Some premenopausal women become marginally iron deficient unless they supplement with iron. However, the 18 mg of iron present in many multivitamin-mineral supplements is often adequate to prevent deficiency. A doctor should be consulted to determine the amount of iron that is needed.

Are there any side effects or interactions?
Supplementation with iron, or iron and zinc, has been found to improve vitamin A status among children at high risk for deficiency of the three nutrients.
People with hepatitis C who have failed to respond to interferon therapy have been found to have higher amounts of iron within the liver. Moreover, reduction of iron levels by drawing blood has been shown to decrease liver injury caused by hepatitis C. Therefore, people with hepatitis C should avoid iron supplements.
Many foods, beverages and supplements have been shown to affect the absorption of iron. Foods, beverages and supplements that interfere with iron absorption include:

• Green tea (Camellia sinensis). This effect may be desirable for people with iron overload diseases, such as hemochromatosis. The inhibitory effect of green tea on iron absorption was 26% in one study
• Coffee (Coffea arabica, C. robusta)
• Red wine, particularly the polyphenol component (also found in tea)
• Phytate (phytic acid), found in unleavened wheat products such as matzoh, pita, and some rye crackers; in wheat germ, oats, nuts, cacao powder, vanilla extract, beans, and many other foods, and in IP-6 supplements
• Whole wheat bran, independent of its phytate content, has been shown to inhibit iron absorption
• Calcium from food and supplements interferes with heme-iron absorption
• Soy protein
• Eggs

Foods and supplements that increase iron absorption include meat, poultry and fish.  Taking vitamin A with iron helps treat iron deficiency, since vitamin A improves the absorption and/or utilization of iron. Although soy protein has been shown to decrease iron absorption (see above), certain soy-containing foods (e.g. tofu, miso, tempeh) have significantly improved iron absorption. Some soy sauces may also enhance iron absorption.

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