Iron, either in the form of heme or non-heme compounds, is essential to life, but it can also pose serious health risks. The liver is a principal target for iron toxicity because it is chiefly responsible for taking up and storing excessive amounts of iron. The major hepatic toxicities of iron overload include damage to multiple cell types (hepatocytes, Kupffer cells, hepatic stellate cells) and to multiple subcellular organelles (mitochondria, lysosomes, and smooth endoplasmic reticulum). Heavy iron overload, as occurs in primary (hereditary) or secondary forms of hemochromatosis, may cause cirrhosis, liver failure, and hepatocellular carcinoma. In addition, iron has been shown to be a contributory factor in the development or progression of alcoholic liver disease, nonalcoholic liver steatohepatitis, chronic viral hepatitis, prophyria cutanea tarda, and, perhaps, in alpha 1-antitrypsin deficiency and end-stage liver disease, regardless of cause.