A 46 year-old man has recently been diagnosed with hereditary haemochromatosis after family screening was carried out at the request of a close relative who was also recently diagnosed with the condition. Your patient has found this a very worrying experience and has understood from his close relative that he is at risk of complications in the future. He comes to discuss this with you. Which of the following complications mentioned by the patient which he thinks can arise from hereditary haemochromatosis, is in fact wrong?