Iron-Deficiency Anemia

Anemia is a reduction in the number of red blood cells (RBCs); in the amount of hemoglobin in the blood (hemoglobin is the iron-containing pigment of the red blood cells that carries oxygen from the lungs to the tissues); and in another related index called hematocrit (the volume of RBCs after they have been spun in a centrifuge). All three values are measured on a complete blood count, which doctors shorten to “CBC.” Iron-deficiency anemia is unique and can be distinguished from other forms of anemia by the fact that it causes RBCs to be abnormally small and pale, an observation easily appreciated by viewing a blood sample through a microscope.

To rule out an iron deficiency in the absence of anemia, a doctor needs to run one or several of a group of special lab tests (such as serum ferritin, which measures the body’s iron stores). People should never be told their body has sufficient iron simply because they are not anemic.

Iron deficiency, whether it is severe enough to lead to anemia or not, can have many non-nutritional causes (such as excessive menstrual bleeding, bleeding ulcers, hemorrhoids, gastrointestinal bleeding caused by aspirin or related drugs, frequent blood donations, or colon cancer) or can be caused by a lack of dietary iron. Menstrual bleeding is probably the leading cause of iron deficiency. However, despite common beliefs to the contrary, only about one premenopausal women in ten is iron deficient.1 Deficiency of vitamin B12, folic acid, vitamin B6, or copper can cause other forms of anemia; many forms of non-nutritional anemia exist, but this article will only cover iron-deficiency anemia.

Checklist for Iron-Deficiency Anemia

Rating Nutritional Supplements Herbs
3Stars Iron
Liver extracts		  
2Stars Vitamin A (as an adjunct to supplemental iron)
Vitamin C (as an adjunct to supplemental iron)		  
1Star Betaine HCl (as an adjunct to supplemental iron)  
3Stars Reliable and relatively consistent scientific data showing a substantial health benefit.
2Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
1Star An herb is primarily supported by traditional use, or the herb or supplement has little scientific support and/or minimal health benefit.

What are the symptoms of iron-deficiency anemia? Some common symptoms of anemia include fatigue, lethargy, weakness, poor concentration, and impaired immune function. In iron-deficiency, fatigue also occurs because iron is needed to make optimal amounts of ATP—the energy source the body runs on. This fatigue usually begins long before a person is anemic. Said another way, a lack of anemia does not rule out iron deficiency in tired people. Another symptom of anemia, called pica, is the desire to eat unusual things, such as ice, clay, cardboard, paint, or starch. Advanced anemia may also result in lightheadedness, headaches, ringing in the ears (tinnitus), irritability, pale skin, unpleasant sensations in the legs with an uncontrollable urge to move them (restless legs syndrome), and getting winded easily.

How is it treated? Conventional therapy involves a combination of treating the underlying causes of iron deficiency and replacing iron. Common forms of iron include ferrous sulfate (Feosol®, Fer-In-Sol®, Mol-Iron®, Slow Fe®), ferrous fumarate (Femiron®, Feostat®, Fumerin®, Hemocyte®, Ircon®), ferrous gluconate (Fergon®, Ferralet®, Simron®), and polysaccharide-iron complex (Niferex®, Nu-Iron®). Common side effects of iron pills include constipation, diarrhea, nausea, and vomiting. Iron may be administered intravenously for those who cannot tolerate the oral forms.

Dietary changes that may be helpful: Iron deficiency is not usually caused by a lack of dietary iron alone. Nonetheless, a lack of iron in the diet is often part of the problem, so ensuring an adequate supply of iron is important for people with a documented deficiency. The most absorbable form of iron, called “heme” iron, is found in meat, poultry, and fish. Non-heme iron is also found in these foods, as well as in dried fruit, molasses, leafy green vegetables, wine, and most iron supplements. Acidic foods (such as tomato sauce) cooked in an iron pan can leech iron into the food and thus also be a source of dietary iron.

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.2 Vegetarians can increase their iron intake by emphasizing iron-containing foods within their diet (see above), or in some cases by supplementing iron, if needed.

Coffee interferes with the absorption of iron.3 However, moderate intake of coffee (4 cups per day) may not adversely affect risk of iron-deficiency anemia when the diet contains adequate amounts of iron and vitamin C.4 Black tea contains tannins that strongly inhibit the absorption of non-heme iron. In fact, this iron-blocking effect is so effective that drinking black tea can help treat hemochromatosis, a disease of iron overload.5 Consequently, people who are iron deficient should avoid drinking tea.

Fiber is another dietary component that can reduce the absorption of iron from foods. Foods high in bran fiber can reduce the absorption of iron from foods consumed at the same meal by half.6 Therefore, it makes sense for people needing to take iron supplements to avoid doing so at mealtime if the meal contains significant amounts of fiber.

Nutritional supplements that may be helpful: Before iron deficiency can be treated, it must be diagnosed and the cause must be found by a doctor. In addition to addressing the cause (e.g., avoiding aspirin, treating a bleeding ulcer, etc.), supplementation with iron is the primary way to resolve iron-deficiency anemia.

If a doctor diagnoses iron deficiency, iron supplementation is essential. Though some doctors use higher amounts, a common daily dose for adults is 100 mg per day. Even though symptoms of deficiency should disappear much sooner, iron deficient people usually need to keep supplementing with iron for six months to one year until the ferritin test is completely normal. Even after taking enough iron to overcome the deficiency, some people with recurrent iron deficiency—particularly some premenopausal women—need to continue to supplement with smaller levels of iron, such as the 18 mg present in most multivitamin-mineral supplements. This need for continual iron supplementation even after deficiency has been overcome should be determined by a doctor.

Liver extracts from beef are a rich natural source of many vitamins and minerals, including iron. Bovine liver extracts provide the most absorbable form of iron—heme iron—as well as other nutrients critical in building blood, including vitamin B12 and folic acid. Liver extracts can contain as much as 3–4 mg of heme iron per gram.

Taking vitamin A and iron together has been reported to help overcome iron deficiency more effectively than iron supplements alone.7 Although the optimal amount of vitamin A needed to help people with iron deficiency has yet to be established, some doctors recommend 10,000 IU per day.

Vitamin C increases the absorption of non-heme iron.8 Some doctors advise iron-deficient people to take vitamin C (typically 100–500 mg) at the same time as their iron supplement.9

Hydrochloric acid produced by the stomach improves the absorption of non-heme iron from food and supplements. 10 11 Some practitioners recommend a hydrochloric acid supplement, e.g., betaine hydrochloride (betaine HCl), to enhance iron absorption in people with iron-deficiency anemia.

A high degree of association between iron-deficiency anemia and vitamin D deficiency in Asian children has been previously reported.12 In three different ethnic groups living in England, iron-deficiency anemia was found to be a significant risk factor for low vitamin D levels in children.13 These findings suggest that children with iron-deficiency anemia should be screened for vitamin D deficiency and be given vitamin D supplements if necessary.

Caution: People who are not diagnosed with iron deficiency should not supplement iron, because taking iron when it isn’t needed does no good and may do some harm.

Are there any side effects or interactions? Refer to the individual supplement for information about any side effects or interactions.

References:

1. Looker AC, Dallman PR, Carroll MD, et al. Prevalence of iron deficiency in the United States. JAMA 1997;277:973–6.

2. Sullivan JL. Stored iron and ischemic heart disease. Circulation 1992;86:1036 [editorial].

3. Morck TA, Lynch SR, Cook JD. Inhibition of food iron absorption by coffee. Am J Clin Nutr 1983;37:416–20.

4. Mehta SW, Pritchard ME, Stegman C. Contribution of coffee and tea to anemia among NHANES II participants. Nutr Res 1992;12:209–22.

5. Kaltwasser JP, Werner E, Schalk K, et al. Clinical trial on the effect of regular tea drinking on iron accumulation in genetic haemochromatosis. Gut 1998;43:699–704.

6. Cook JD, Noble NL, Morck TA, et al. Effect of fiber on nonheme iron absorption. Gastroenterology 1983;85:1354–8.

7. Mejia LA, Chew F. Hematological effect of supplementing anemic children with vitamin A alone and in combination with iron. Am J Clin Nutr 1988;48:595–600.

8. Ajayi OA, Nnaji UR. Effect of ascorbic acid supplementation on haematological response and ascorbic acid status of young female adults. Ann Nutr Metab 1990;34:32–6.

9. 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.

10. Schade SG, Cohen RJ, Conrad ME. Effect of hydrochloric acid on iron absorption. N Engl J Med 1968;279:672–4.

11. Bezwoda W, Charlton R, Bothwell T, et al. The importance of gastric hydrochloric acid in the absorption of nonheme food iron. J Lab Clin Med 1978;92:108–16.

12. Grindulis H, Scott PH, Belton NR, Wharton BA. Combined deficiency of iron and vitamin D in Asian toddlers. Arch Dis Child 1986;61:843–8.

13. Lawson M, Thomas M. Vitamin D concentrations in Asian children aged 2 years living in England: population survey. BMJ 1999;318:28.