We studied the relationship between iron removed by venesection, sex, age, and clinical characteristics in a group of 100 Spanish probands with hereditary hemochromatosis (HH), all C282Y homozygous in the HFE gene. Iron overload was higher in men than in women (P < 0.0001) and increased with age (P = 0.02). Forty-four patients presented with liver disease (28 had fibrosis-cirrhosis of the liver), 24 with diabetes, 18 with arthropathy, and 13/73 men with impotence. No clinical consequences of hemochromatosis were observed in 43 patients. The number of clinical complications was higher in men (P = 0.01) and increased with age (P = 0.006) and with the amount of iron removed (P < 0.0001). The amount of iron removed was significantly higher by univariate analysis in patients with liver disease (P < 0.0001), diabetes (P = 0.007), arthropathy (P = 0.006), and impotence (P = 0.003) than in patients without these complications. In the multivariant analysis, only liver disease maintained a significant relationship with the amount of iron removed (P < 0.0001). Diabetes and arthropathy were closely related with previous liver disease, and impotence appeared mainly in hemochromatosic men with diabetes and alcoholism.