Merck Manual

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Overview of Iron Overload

(Hemosiderosis; Hemochromatosis)


James Peter Adam Hamilton

, MD, Johns Hopkins University School of Medicine

Reviewed/Revised Sep 2022
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Typical adults lose about 1 mg iron (Fe) per day in shed epidermal and gastrointestinal cells; menstruating females lose on average an additional 0.5 to 1 mg/day from menses. This iron loss is balanced by absorption of a portion of the 10 to 20 mg of iron in a typical US diet. Iron absorption is regulated based on the body's iron stores and is usually in balance with the body's needs. However, because there is no physiologic mechanism to remove iron from the body, iron absorbed in excess of bodily needs (or acquired through repeated transfusion) is deposited in tissues.

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 pathogenesis of African iron overload, but no gene has yet been identified.

Overview of Hemochromatosis

General references

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