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In 1992, average life expectancy at birth in the U.S. was 75.8 years. By 2008 that had risen by over 2 years to 78.1 years. The most recent data (2013) from the Centers for Disease Control finds that it is now 78.8 years on average. A rough calculation finds that life expectancy is increasing at a rate of about 2 months for every year that passes. In general, longer life is a good, but longer healthier life is even better. The good news is that even as life expectancy lengthens, healthy life expectancy is increasing even faster, according to a new National Bureau of Economic Research study by researchers associated with Harvard University. The researchers focus on increases in life expectancy for American over age 65 and report:
Years of healthy life expectancy at age 65 increased by 1.8 years over that time period, while disabled life expectancy fell by 0.5 years….[and then] we identify the medical conditions that contribute the most to changes in healthy life expectancy. The largest improvements in healthy life expectancy come from reduced incidence and improved functioning for those with cardiovascular disease and vision problems. Together, these conditions account for 63 percent of the improvement in disability-free life expectancy.
The increase in disability-free life expectancy for Americans over age 65 is largely the result of improved medical care. Specifically, cataract surgery and prophylactic treatments that prevent heart disease such as medications to lower blood pressure have significantly reduced the incidence of disabilities experienced by earlier generations at younger ages. This is good news, but the health care system is still far away from longevity escape velocity, that is, when increases in life expectancy rise faster than the time that passes. In other words, longevity escape velocity will be achieved when instead of rising at merely 2 months per year, life expectancy lengthens faster than 12 months per year.
For more background, see my Reason cover article, "Eternal Youth for All!"
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