A condition in which too much iron builds up in the body over time. Without treatment, this extra iron can damage the organs, mainly the liver, heart, and pancreas, and cause organ failure. Hemochromatosis is one of the most common genetic diseases in the United States. But iron overload also can happen due to other diseases or from years of taking too much iron or from repeated blood transfusions or dialysis for kidney disease. The most common treatment to remove extra iron is to remove some blood.