Iron : Uses and Health Benefits

by MedlinePlus

Iron is an essential mineral and an important component of proteins involved in oxygen transport and metabolism. Iron is also an essential cofactor in the synthesis of neurotransmitters such as dopamine, norepinephrine, and serotonin. About 15 percent of the body's iron is stored for future needs and mobilized when dietary intake is inadequate. The body usually maintains normal iron status by controlling the amount of iron absorbed from food.

There are two forms of dietary iron: heme and non-heme. Sources of heme iron include meat fish and poultry. Sources of non-heme iron, which is not absorbed as well as heme iron, include beans, lentils, flours, cereals, and grain products. Other sources of iron include dried fruit, peas, asparagus, leafy greens, strawberries, and nuts.

The World Health Organization considers iron deficiency to be the largest international nutritional disorder. Although much of the ethnic disparity in iron deficiency anemia remains unexplained, socioeconomic factors may be involved.

Iron deficiency can be determined by measurement of iron levels within the body, mainly serum ferritin levels, which can also help distinguish between iron deficiency anemia and anemia associated with chronic disease.

Herbal preparations such as yellow dock root may be used in iron deficiency, although scientific evidence may be lacking.

Synonyms

Atomic number 26, carbonyl iron, dextran-iron, elemental Iron, FE, Fer, ferrous carbonate anhydrous, ferrous fumarate, ferrous gluconate, ferrous pyrophosphate, ferrous sulfate, iron dextran, iron-polysaccharide, iron sorbitol, Iron sucrose, sodium ferric gluconate.

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Uses based on scientific evidence

Iron deficiency anemia

Ferrous sulfate (Feratab®, Fer-Iron®, Slow-FE®) is the standard treatment for treating iron deficiency anemia. Under the supervision of a qualified healthcare provider, patients usually continue taking iron for about two months after correction of the anemia and its cause to assure adequate body stores. Dextran-iron (INFeD®) is given intravenously by healthcare providers to restore adequate iron levels in bone marrow when oral iron therapy has failed.Supplemental iron can normalize serum ferritin, but may not raise low hemoglobin in chronic undernutrition and multiple micronutrient deficiency. Supplemental iron absorption is decreased in people requiring chronic hemodialysis. Iron overload is likely to occur in people with hemoglobinopathies or other refractory anemias erroneously diagnosed as iron deficiency anemia.

Anemia of chronic disease

Taking iron orally with epoetin alfa (erythropoietin, EPO, Epogen®, Procrit®) is effective for treating anemia associated with chronic renal failure and chemotherapy.

ACE inhibitor-associated cough

Taking iron orally seems to inhibit cough associated with angiotensin converting enzyme (ACE) inhibitors. Ferrous sulfate 256 mg daily might reduce or eliminate cough associated with ACE inhibitors such as captopril (Capoten®), enalapril (Vasotec®), Lisinopril (Prinivil®, Zestril®), and others.

Prevention of iron deficiency anemia in pregnancy

Iron supplements have been shown to help prevent iron deficiency anemia in pregnant women. Anemia in pregnant women is associated with adverse outcomes such as low birth weight, premature birth, and maternal mortality. Screening by a qualified healthcare provider is needed. Low doses are generally well tolerated and associated with better compliance.

Preventing iron deficiency in menstruating women

Iron supplementation has been shown to improve iron status in menstruating women.

Preventing anemia associated with preterm/low birth weight infants

Further study of prenatal iron supplementation is needed before a firm recommendation can be made regarding effects of anemia on preterm/low birth weight infants.

Preventing iron deficiency in exercising women

Preliminary studies suggest that iron supplementation can reverse mild anemia after exercise, improve energy and performance. However, other studies disagree. Further research is needed in this area before firm recommendations can be made.

Treatment of predialysis anemia

Adequate iron supplementation may allow the target hematocrit to be reached without, or with only very low doses of erythropoietin. The advantage of maintaining adequate iron stores with intravenous iron is that if erythropoietin is needed, lower doses will be required to achieve the target hemtocrit than if erythropoietin were used alone. This not only avoids the high cost of erythropoietin therapy but also its associated side effects, especially high blood pressure. It is important that accurate assessment of iron needs by a mathematical method is used to enhance treatment efficacy and avoid iron overload in hemodialysis patients on rHuEPO therapy. Predialysis anemia should be treated by a qualified healthcare provider.

Improving cognitive performance related to iron deficiency

Taking iron orally seems to improve cognitive function related to iron deficiency in iron-deficient children and adolescents. Further research is needed to confirm the potential benefit of iron in this indication. Iron supplements are not recommended for improving cognitive performance in non- iron deficient people.

Attention deficit-hyperactivity disorder (ADHD)

Based on preliminary data, taking iron orally might improve symptoms of attention deficit-hyperactivity disorder (ADHD). More study is necessary before a conclusion can be drawn.

Lead toxicity

Iron deficiency may increase the risk of lead poisoning in children.A number of epidemiologic studies have found iron deficiency to be associated with increased blood lead levels in young children. Iron deficiency and lead poisoning share a number of the same risk factors, but iron deficiency has been found to increase the intestinal absorption of lead in humans and animals. However, the use of iron supplementation in lead poisoning should be reserved for those individuals who are truly iron deficient or for those individuals with continuing lead exposure, such as continued residence in lead-exposed housing.

Fatigue in women with low ferritin levels

Ferrous sulfate 80mg daily may improve fatigue primarily in women with borderline or low serum ferritin concentrations. Further research is needed to confirm these results.

Prevention of iron deficiency after blood donation

The results of early study indicate that 20 mg of elemental iron per day can adequately compensate for iron loss in males and females who donate whole blood up to four (females) or six times per year (males).

Prevention of iron deficiency anemia due to gastrointestinal bleeding

A single intravenous high-dose iron sucrose therapy inpatients with IDA due to gastrointestinal blood loss appears to be safe and therefore is a therapeutic option which may save time and improve patient compliance.

Therapy for anemia after orthopedic surgery

Early study reports that iron taken after elective hip or knee replacement surgery does not result in higher hemoglobin 10 weeks after surgery, or a faster rate of increase in hemoglobin than a placebo.

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Anemia in anorexia nervosa, arm tremor, Crohn's disease, cystic fibrosis, depression, female infertility, fatigue, helping growth and development, improving athletic performance, menorrhagia, pagophagia (compulsive eating of ice), preventing running performance deterioration in children, prevention of anemia in blood donors, restless leg syndrome, strengthening the immune system, treating oral canker sores.

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