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Iron deficiency anemia is a condition in which blood lacks adequate red blood cells. Iron deficiency is the most common nutrient deficiency in the United States. Iron is critical to human life. It plays the central role in the hemoglobin molecule of our red blood cells, where it is essential in the process of transporting oxygen from the lungs to the body’s tissues. It also functions in several key enzymes in energy production and metabolism, including DNA synthesis.
At Risk for Iron Deficiency
The groups at highest risk for iron deficiency are infants under 2 years, teenage girls, menstruating women, pregnant and nursing women, and the elderly. Increased requirements occur during the growth spurts of infancy and adolescents. Unfortunately, typical infant diets (high in milk and cereals) are low in iron, as are typical adolescent junk-food diets. Those at greatest risk, however, are low-income seniors. This is complicated by the fact that decreased absorption of iron—often due to a lack of hydrochloric acid production in the stomach—is common in the elderly.
Symptoms & Diagnosis
The negative effects of iron deficiency are due largely to the impaired delivery of oxygen to the tissues and the impaired activity of iron-containing enzymes in various tissues. The symptoms of anemia, such as extreme fatigue, reflect a lack of oxygen being delivered to tissues and a buildup of carbon dioxide.
Anemia is actually the last stage of iron deficiency. Low iron levels first affect iron-dependent enzymes involved in energy production and metabolism. Even a slight iron deficiency leads to a reduction in physical work capacity and productivity. Supplementation with iron has shown rapid improvements in work capacity in iron-deficient individuals.
Impaired immune function is another symptom. Iron deficiency greatly reduces the immune system’s ability to fight off infection, and can also lead to altered white blood cell concentrations and defective white blood cell function. Iron deficiency may be the responsible factor in many individuals suffering from chronic infections or frequent colds.
Iron deficiency is also associated with impaired brain function, including decreased attentiveness, a narrower attention span, decreased persistence, and decreased voluntary activity. These symptoms can be especially present in children, making iron deficiency a leading contributor to learning disabilities. Fortunately, with iron supplementation there is a return to normal mental function.
If you notice any of these symptoms and suspect that you may have an iron deficiency, there are several tests available. The most sensitive by far is a blood test that measures serum ferritin, the iron storage protein. Other measures of iron stores—such as serum iron, total iron binding capacity, and hemoglobin—are less sensitive, but often performed on a routine basis.
Diet & Supplements
The best dietary source of iron is red meat, especially liver. Other good sources include fish, beans, molasses, dried fruits, whole-grain and enriched breads, and green leafy vegetables. Regardless of diet, iron supplementation is often required to raise levels, especially during pregnancy and in menstruating women. Ferrous sulfate is the most popular supplement, but it is less than ideal, as it often causes constipation or other gastrointestinal (GI) disturbance. Although it’s best absorbed when taken on an empty stomach, doing so often causes nausea or GI upset. So it’s most often taken with food, which greatly reduces its absorption. Currently, the best sources of iron in supplements appear to be a special form of ferric pyrophosphate and ferrous bisglycinate. Both are free from GI side effects with a high relative bioavailability, especially if taken on an empty stomach.
For iron deficiency, up to 60 mg daily in divided doses may be recommended. For general health purposes, the RDA should be used as a supplementation guideline (See sidebar, p. 18). High intakes of other minerals, particularly calcium, magnesium, and zinc can interfere with iron absorption, so when treating iron deficiency, try to take iron without these minerals. In contrast, vitamin C enhances iron absorption.
Remember to keep all iron supplements out of the reach of children and infants. Iron poisoning can result in damage to the intestinal lining, liver failure, nausea and vomiting, and shock.
1. FLORAFloravital Iron + Herbs is the gluten- and yeast-free form of Flora’s popular liquid Floradix formula, with 10 mg of iron per capful plus energizing B vitamins.
2. THE VITAMIN SHOPPEIron delivers 28 mg of iron per tablet, and includes vitamin C and other nutrients for better iron absorption.
3. MEGAFOODBlood Builder is an easy-to-digest formula including whole-food derived iron and vitamin C that can be taken on an empty stomach.
4. NATURAL FACTORSEasy Iron is a chewable tablet featuring ferric pyrophosphate, a highly bioavailable form of iron free of gastrointestinal side effects.
Michael T. Murray, ND, is the author of more than 30 books, including The Complete Book of Juicing, Revised and Updated. He is regarded as one of the world’s top authorities on natural medicine. Visit him online at doctormurray.com.