The Aging Process Why should the human body give out after 70, 80, or even 120 years? Why are older people more susceptible to disease, more inclined to have impaired vision and hearing, and likely to lose some of the physical and mental capacity they once enjoyed? There are no fully satisfactory answers to these questions. Although we are mortal, it is entirely possible that one day humans could live much longer. The present potential life span for humans is said to be 115 years and today thousands of people live to be over 100. United States citizens now expect to live an average of 74.7 years. Women ha