The new, April, issue of National Geographic has maps of life expectancy for each county in the United States for 1989 and for 2009. (Apparently the digital version allows you to click on any particular county and get the local information, once you shell out $19.95 for a digital subscription.)
The story emphasizes the fact that life expectancy for men has increased more than it has for women over these 20 years and suggests that this may be due to inadequate treatment for women with high blood pressure and cholesterol. But it seems to me (though I am no epidemiologist) that that discrepancy might be due to the fact that women live longer than men and thus have less upside potential.
To me, the most startling fact in this data dump is just how fast life expectancy has increased for both sexes: 4.6 years for men and 2.7 years for women. That’s a 6.4 percent increase for men and a 3.4 percent increase for women in just two decades.
There was a similar leap in life expectancy in the early 20th century, but that increase was due to much lower infant and childhood mortality thanks to vaccines against such child-killers as whooping cough and diphtheria and the mandated pasteurization of milk, which eliminated the horrendous number of infant deaths caused by impure milk.
This latter-day increase comes at the end of life. Partly it is due to medicine’s greatly increased ability to cure or manage such killers as pneumonia, heart disease, and cancer. Partly it is due to a greatly improved environment, especially in cities and factories. And partly it is due to improved life styles, with more exercise and less fat, alcohol and tobacco.
There is no reason to think that this increase in life expectancy will abate any time soon. Indeed, it may accelerate. And that has tremendous public-policy implications with regard to Social Security, Medicare, etc. And as the percentage of old people increases in the population, their political clout will increase with it.