What is it? Overview Usage Side Effects and Warnings

What is Iron?

The element iron is essential to human life. As part of hemoglobin, the oxygen-carrying protein found in red blood cells, iron plays an integral role in nourishing every cell in the body with oxygen. It also functions as a part of myoglobin, which helps muscle cells store oxygen. Without iron, your body could not make ATP (adenosine triphosphate, the body's primary energy source), produce DNA, or carry out many other critical processes.

Iron deficiency can lead to anemia, learning disabilities, impaired immune function, fatigue, and depression. However, you shouldn't take iron supplements unless lab tests show that you are genuinely deficient.

The most obvious use of iron supplements is to treat iron deficiency. Severe iron deficiency causes anemia, which in turn causes many symptoms. Iron deficiency too slight to cause anemia may impair health as well. Several, though not all, double-blind trials suggest that mild iron deficiency might impair sports performance . 1 In addition, a double-blind, placebo-controlled study of 144 women with unexplained fatigue who also had low or borderline-low levels of ferritin (a measure of stored iron) found that iron supplement enhanced energy and wellbeing. 2 Another study found that iron supplements improved mental function in women who were iron deficient. 3 However, don't take iron just because you feel tired. Make sure to get tested to see whether you are indeed deficient. With...

Safety Issues

Iron supplements commonly cause gastrointestinal upset, but, when taken at recommended dosages, serious adverse consequences are unlikely. However, excessive dosages of iron can be toxic—damaging the intestines and liver, and possibly resulting in death. Iron poisoning in children is a surprisingly common problem, so make sure to keep your iron supplements out of their reach.

Mildly excessive levels of iron may be unhealthy for another reason: it acts as an oxidant (the opposite of an antioxidant), perhaps increasing the risk of cancer and heart disease (although this is controversial). 4 Elevated levels of iron may also play a role in brain injury caused by stroke . 5 In addition, excess iron appears to increase complications of pregnancy , 6 and,...