The Evolution of the Mortality Curve: Changes in the Age of Minimum Mortality

Eileen Crimmins, University of Southern California
Greg L. Drevenstedt, University of Southern California
Caleb E. Finch, University of Southern California

The shape of the age-specific mortality curve has long been viewed as constant: with very high mortality at both ends of the age range and with lower levels of mortality after childhood and before the beginning of old age. Demographers have tended to focus their analysis on the ages of high mortality and paid little attention to the age at minimum mortality; biologists, on the other hand see the age at minimum mortality as the point in the lifespan when the organism has successfully passed through development and becomes subject to the forces of mortality that eventually result in senescence. The age at minimum mortality has been dropping in recent decades in many countries of the world. We hypothesize that this earlier age of lowest mortality is connected to an earlier age of physical development or maturity that accompanies the epidemiological and nutritional revolutions that have resulted in longer life.