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A majority of older workers tell pollsters they expect to continue working, at least part-time, during their retirement years. There are plenty of financial reasons to do that - inadequate savings, volatile 401(k) plans. And some research suggests another reason to keep working, it may keep you mentally and physically fit. And then again, there's also research that says just the opposite.
NPR's Ina Jaffe has this installment of our series on retirement.
(SOUNDBITE OF MUSIC)
INA JAFFE, BYLINE: This is old Hollywood. The Musso and Frank Grill, usually just called Musso and Frank's, it's all dim lighting, curved booths and a soundtrack featuring every song you ever heard in a black and white movie. It's a steak and martini kind of place.
MANUEL AGUIRRE: And we pour three ounces. That's a good drink.
JAFFE: And this guy would know. Manuel Aguirre, known to his devoted fans as Manny, has been mixing cocktails for 55 years, more than two decades of that behind the long bar here at Musso and Frank's. He just turned 80. He could retire if he wanted to.
AGUIRRE: My kids and my grandchildren, they say to me, Grandpa, it's time. But they don't realize you miss part of your life, your customers and your friends.
JAFFE: One of whom is 82-year-old waiter Alonzo Castillo, aka Panama. He's worked here for 40 years.
ALONZO CASTILLO: I like it here, so I keep for working.
JAFFE: Though, like Manny, he works part-time. Also, like Manny, Panama says he could retire if he wanted.
CASTILLO: But I want to keep in shape, you know. If I stay home, I will start watching TV.
CASTILLO: You know, what I mean? So the best thing for everyone is to work at least part-time.
JAFFE: That theory that working or volunteering a lot keeps older people physically and mentally sharp is something that researchers have been trying to confirm. And there's a large pool of data for them to use. It's the University of Michigan's Health and Retirement Study. It's tracked thousands of older Americans for more than two decades.
Economist Dhaval Dave, a research fellow with the National Bureau of Economic Research, says his look at the data showed that retirement is not so good for your health.
DHAVAL DAVE: Once they retire completely we found that there are increases in depression and mental illness. There are increases in certain health conditions like arthritis, hypertension. For the average American, we found negative affects on health.
JAFFE: Retirement also has a negative effect on cognition, according to Susann Rohwedder, the associate director for the study of aging at the RAND Corporation.
SUSANN ROHWEDDER: What we find is a sizable cognitive decline in response to retirement. And it is a five-and-a-half point decline on a 20 point scale. So it is a really large effect.
JAFFE: But the same pool of numbers, used by Dave and Rohwedder, yielded very different results when crunched by Michael Insler, an economics professor at the Naval Academy.
MICHAEL INSLER: On average, there's a beneficial effect for the retiree.
JAFFE: You heard right. Insler found retirement is good for your health.
INSLER: In the study, I look at nine health conditions: cancer, lung problems, heart problems, things like that. And I found that the decision to retire brings about a one-third to a one-quarter decrease in the incidents of these types of disorders.
JAFFE: It's not that surprising that researchers disagree, says Dr. Edward Schneider. He's a professor of gerontology at the University of Southern California and the former deputy director of the National Institute on Aging. He says there are as many versions of retirement as there are people who've retired.
DR. EDWARD SCHNEIDER: There's so many different factors that come into play. Are you retiring 'cause you want to? Are you retiring involuntarily? Are you working or volunteering after retirement? These are all critical factors in terms of your mental health, and I think they also affect your physical health.
JAFFE: It's basically impossible to construct a sound scientific experiment that would determine the health impacts of work and retirement, says Schneider. Because here's what you'd have to do...
SCHNEIDER: Randomly assign people who are working to two groups. One group that would continue working and the other group that would retire.
JAFFE: Sure, people would love to give up control over their lives in the interest of science.
SCHNEIDER: We'd follow them over a period of years and then look at their mental and physical health.
JAFFE: But until we all submit to our scientific overlords, we have the extremely small unscientific sample group of Manny and Panama at the Musso and Frank Grill. And they do not seem ready to quit show business. Panama looks around the restaurant and points out where the stars sat when he served them.
CASTILLO: Like John Wayne, I serve him before, Raymond Burr sitting in this table.
JAFFE: Raymond Burr?
CASTILLO: Raymond Burr. Remember Raymond - Perry Mason.
JAFFE: And Manny keeps a scrapbook full of snapshots of him posing with every famous person who's ever sat at his bar. There's Keith Richards...
AGUIRRE: Rolling Stone...
AGUIRRE: Rolling Stone.
JAFFE: Johnny Depp.
AGUIRRE: Mickey Rooney.
UNIDENTIFIED MAN: Mickey Rooney, right here.
AGUIRRE: Francis Coppola, Drew Barrymore.
JAFFE: The stars come, the stars go. Manny and Panama remain. Ina Jaffe, NPR News.
AGUIRRE: Larry King, he was sitting here.
JAFFE: Jack Lemmon, you wait on him?
AGUIRRE: Beefeater martini.
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