Overview of Iron Overload

ByJames Peter Adam Hamilton, MD, Johns Hopkins University School of Medicine
Reviewed/Revised Sept 2022
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    Iron is essential for life, so the body usually tightly controls iron absorption from food and recycles the iron from red blood cells. People lose small amounts of iron every day, and even a healthy diet contains only a small amount of iron. Thus, people rarely have too much iron in their body. Causes of excess iron in the body (iron overload) include the following:

    • A genetic disorder that increases iron absorption (hemochromatosis)

    • Repeated blood transfusions

    • Taking too many pills containing iron

    • Excessive breakdown of red blood cells

    When the body gradually takes in more iron than it needs, the excess iron is deposited in tissues throughout the body. Symptoms and complications can occur if iron accumulates in the endocrine organs (especially the pancreas, gonads, and pituitary gland), liver, or heart.

    Taking in a large amount of iron all at once, such as in an overdose of iron pills, can be very dangerous. Iron poisoning damages the digestive tract, liver, heart, and brain, and it can be fatal.

    African iron overload occurs most often in sub-Saharan Africa among people who consume an iron-rich fermented drink. A genetic component is thought to contribute to the development of African iron overload, but no gene has yet been identified.

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