In this open letter, Jobs said that, "As many of you know, I lost a lot of weight in 2008 and neither I nor my doctors could find the cause. Several weeks ago, I thought that it was most important to find out the root of this problem and treat it. Fortunately, after further examination, my doctor thought that he had found the cause: hormonal imbalance made me lose proteins necessary for maintaining health. Further blood tests also confirmed this diagnosis."