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BOB HIRSHON (Host):
Do humans have an expiration date? I’m Bob Hirshon and this is Science Update.
In the 1950s, there were only about 20,000 people over the age of 100; today, there are about a half-million. Human lifespan keeps getting longer, but can it continue? In the journal Science, UC Berkeley evolutionary demographer Kenneth Wachter and his colleagues suggest that it can. He says that while death rates increase exponentially as you get older, that rate increase slows after you reach 80, and if you make it to 105, your year-over-year risk of death actually goes down.
KENNETH WACHTER (University of California, Berkeley):
So it’s not that rates go down and if you live to 105 you’re in clover. Rates are high, but they’re not getting worse, and they’re leveling out.
That suggests that human lifespan isn’t coming against any sort of a hard limit.
That doesn’t mean there couldn’t be a limit, but it’s not around the corner.
I’m Bob Hirshon, for AAAS, the science society.
Story by Bob Hirshon