We are the only living beings on the planet who are conscious that some day we will not exist. Nevertheless, we are still determined to break the barriers that keep us from prolonging our presence in this world. We want to prolong life and enjoy it under the best physical and mental conditions. During the first few decades of this century the predictions warned us about the alarming increase of different diseases. At the same time, others talked about impending discoveries like the curing of AIDS or the definitive triumph in the battle against cancer.