Increases in body iron may be due to increased absorption (hemochromatosis), increased oral intake of non-therapeutic iron, unneeded iron therapy, or multiple blood transfusions in the absence of bleeding. The excess iron is deposited in body tissues, and can reach toxic levels leading to organ damage. The toxicity can affect most tissues and organs, but particularly the liver, causing cirrhosis; the endocrine system, causing diabetes, hypogonadism, and sometimes hypoparathyroidism; and the heart, causing arrhythmias and cardiomyopathy.