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In this country we're getting a more specific idea of what affects your life expectancy. One factor is money - rich people tend to live longer. Now a study explores the poor people who as a group tend to live shorter lives. The study in the Journal of the American Medical Association breaks down that big demographic group and finds that some poor people live longer than others. NPR's Jim Zarroli reports on why.
JIM ZARROLI, BYLINE: Researchers looked at a vast amount of data - more than a billion records from the Treasury Department and the Social Security Administration. They found that men in the top 1 percent of income levels tend to live almost 15 years longer than men in the bottom 1 percent. Since 2000, life spans have increased 2.3 years for the highest-income men and almost three years for the highest-income women. Life expectancy for those at the bottom hasn't increased much at all. But the data also show wide disparities from place to place, says the study's lead author, Stanford University economics professor Raj Chetty.
RAJ CHETTY: There are some places where the poor are doing quite well, gaining just as much in terms of life span as the rich. But there are other places where they're actually going in the other direction, where the poor are living shorter lives today than they did in the past.
ZARROLI: In Birmingham, Ala., low-income people are doing about as well as the rich. But in Tampa, Fla., life expectancy for the poor has actually been falling. And Chetty says the poor tend to live longest in affluent, highly-educated cities. The poorest people live longer in San Francisco than in Detroit. Why this is is unclear, Chetty says. But the data show that life spans are closely tied to behavioral factors - low rates of smoking and obesity, for instance. It may be that some cities are simply better at promoting healthier lifestyles - with smoking bans, for instance. Or perhaps people tend to adopt healthier habits if they live in cities where everyone else is doing it. At any rate, Chetty says, the data suggests that the challenge of addressing life expectancy differs from city to city.
CHETTY: What our study shows is thinking about these issues of inequality and health and life expectancy at a local level is very fruitful and thinking about policies that change health behaviors at a local level is likely to be important.
ZARROLI: Chetty says the study has implications for Social Security and Medicare. Because wealthy people live longer, they're also dependent on entitlement programs longer and ultimately cost these programs more money. Chetty says there have been suggestions that these programs be indexed to account for longer life spans. But the data suggests the gains in life expectancy aren't being shared equally. Jim Zarroli, NPR News, New York.
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