Summary

The last chapter of The Body: A Guide for Occupants deals with the end of life. In 2011, humanity reached the point at which more people died from non-communicable diseases like heart failure and diabetes than infectious diseases. However, death today often takes longer with about 60 percent of deaths occurring after a protracted decline. Although we have gotten better at extending life, quality of life in old age has not gotten much better. And there are many costs to living longer. Elderly people in the United States occupy half the hospital beds and consume a third of medicines, Bryson writes. People spend more time in retirement now, although they do not often work more to fund their longer lives.

Medical science cannot entirely explain the process of aging. In 1961 a researcher discovered human stem cells divide about fifty times before they lose their...