Iron is one of the most abundant minerals on earth. It is essential to the majority of life forms, especially human physiology. Iron supports prenatal and cognitive health, as well as energy balance.
Iron is an integral component of the proteins involved in oxygen transport and storage: hemoglobin, myoglobin and ferritin. Iron, as part of the protein hemoglobin, carries oxygen from the lungs to various parts of the body. Hemoglobin accounts for nearly two-thirds of the iron found in the body, and carries essential oxygen to tissues and organs. Approximately onesixth of the body’s iron is stored as ferritin for use when dietary intake is not sufficient.
Health Category information
Iron supplements are often a standard recommendation for the treatment of fatigue, particularly among women. A 2012 randomized study confirmed the efficacy of iron in supporting energy balance.
French researchers studied nearly 200 menstruating women ages 18 to 53 who complained of fatigue but were otherwise healthy. All subjects had lower-than-normal ferritin levels (less than 50 mcg per liter). During the study, half of the subjects took 80 mg of iron daily, while the other half took a placebo. Fatigue was measured using a validated questionnaire at the beginning and end of the study.
At the close of 12 weeks, patients receiving the iron pills reported favorable outcomes related to fatigue and energy balance compared to the placebo group. The researchers also found that iron supplements increased the production of red blood cells. 
Several major health organizations recommend iron supplementation during pregnancy to ensure pregnant women meet their iron requirements for healthy pregnancy outcomes. For all pregnant women, the Centers for Disease Control and Prevention recommends routine low-dose iron supplementation beginning with the first prenatal visit. Larger doses of iron may be recommended following thorough testing to determine low hemoglobin or hematocrit.
In a 2013 study, published in the Canadian Medical Association Journal, daily iron supplementation was shown to support outcomes associated with cognitive health, including attention and concentration. Additionally, the same study found that healthy outcomes were supported related to incidences of general iron deficiency.
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