Iron is an essential element to all living organisms. It is a component of many proteins with important functions in physiological processes such as oxygen transport, respiration, DNA synthesis, cell cycle regulation and many others. Free iron is highly reactive and its excess can lead to tissue and organ damage. Intestinal absorption of iron is precisely regulated because there is no excretory mechanismfor excessive iron. Improvedmethodology led to the identification of many genes and proteins involved in the iron metabolism and to the understanding of basic processes of iron intake, transport and storage. However, some aspects remain still unclear – primarily the regulation of iron intake according to the body’s requirements. Disorders of iron metabolism, both the deficiency and the overload belong to relatively common diseases. Growing understanding of the physiology of the iron metabolism is rapidly reflected in diagnostics, preventive screening and therapy of the iron disorders.

        Key words: iron, hemochromatosis, transferin, ferritin, hepcidin, sideropenia, haptoglobin, hemoxygenase, hemopexin, anemia.