An article I stumbled across today, lightweight as it is, convinces me that measuring aging by mortality risk is more elegant that the traditional method of counting years. Doing so factors in some degree of ongoing progress in medical science, some degree of the ongoing accumulation of cellular and molecular damage, and I'm an easy sell for any yardstick that manages that.
He argues that age should be calculated not by years since birth but by years left to live. With data from the 2000 census, he has reconfigured the calendar of aging ... according to his mortality risk measure, you aren't old unless you have a 4 percent risk, Shoven says. That's a 1-in-25 chance of dying within the year, which could well translate into a lengthy old age. Today people don't begin to get old until their 70s. Middle age - defined by a mortality risk between 1 and 4 percent - doesn't start for a man until he is 58!Just like dollars, years of age don't have the same value as they did in the past. In 1940 a man in his late 40s had the same mortality risk as a man in his late 50s today. A woman in 1940 crossed the threshold into old age when she was in her late 60s. Today she would be in her late 70s.
Neither years nor mortality risk from census data says anything about your deviation from the average, of course. How healthy are you, how much damage have you sustained? Those of us with an interest in personal longevity should all be working on pushing that deviation upward - every extra year of healthy life is worth a great deal when the rate of progress in biotechnology and medical science is as rapid as it is at present. Work your own way to an additional year, and you will benefit from another year of new technologies aimed at helping you live longer in good health.