Teddy Roosevelt once said “the best prize that life has to offer is the chance to work hard at work worth doing.” Recent research suggests he may have been more right than he knew: Life’s “best prize” might actually extend life itself.

Our common perception is that retirement is a time when we can relax and take better care of ourselves after stressful careers. But what if work itself is beneficial to our health, as several recent studies suggest?

One of them, by Jennifer Montez of Harvard University and Anna Zajacova of the University of Wyoming, examined why the gap in life expectancy between highly educated and less-educated Americans has been growing so rapidly. (I have explored this topic in several previous columns, and have also agreed to be co-chairman of a National Academy of Sciences panel that will delve into it in more detail.)

Examining the growing educational gradient in life expectancy from 1997 to 2006, Montez and Zajacova focused on white women ages 45 to 84. In addition to differential trends in smoking by education, they concluded that among these women “employment was, in and of itself, an important contributor.” The life expectancy of less-educated women was being shortened by their lower employment rates compared with those of highly educated women.

The researchers tried to test whether the problem was that less-educated people had worse health, and therefore couldn’t work. But they found that “the contribution of employment to diverging mortality across education levels is at least partly due to the health benefits derived from employment.”

Unhealthy Retirement

Researchers at the Institute of Economic Affairs in the U.K. have also recently identified “negative and substantial effects on health from retirement.” Their study found retirement to be associated with a significant increase in clinical depression and a decline in self-assessed health, and that these effects grew larger as the number of years people spent in retirement increased.

Similarly, a study published in 2008 by the National Bureau of Economic Research found that full retirement increased difficulties with mobility and daily activities by 5 percent to 16 percent and, by reducing physical exertion and social interactions, also harmed mental health.

The broader literature on the question of whether retirement harms health has been more mixed. The big question is whether the observed physical deterioration after retirement occurs because it is underlying poor health that leads people to end their working life. Some studies that try to control for this reverse causality, such as a 2007 paper by John Bound of the University of Michigan and Timothy Waidmann of the Urban Institute, find that retirement doesn’t harm health -- and may actually improve it. Another study, by Esteban Calvo of the Universidad Diego Portales in Chile, Natalia Sarkisian of Boston College and Christopher Tamborini of the Social Security Administration, finds harm from early retirement but no benefit from delaying retirement beyond the traditional age.

My own reading of all of these studies is that there is at least strongly suggestive evidence that not working, in and of itself, can be harmful to your health. And this raises the question of what it means for the puzzling finding that overall life expectancy appears to rise, not fall, during recessions.

Now I’m only speculating, but the answer could lie in the fact that, even during a recession, most people still work. Because a larger-than-usual minority don’t, pollution is reduced, traffic fatalities decline and the quality of staffing at nursing homes improves -- and these changes boost the health of the people who are still working. It’s terrible to say, but the research seems to suggest that being out of work yourself may hurt your health -- but having other people out of work may help it.

Which brings us back to Mr. Roosevelt. Most of us seem to think that we would be in better health if we won the lottery and spent our days on the beach, rather than struggling with sometimes stressful jobs. Yet the next time you think your job is killing you, just remember that the evidence, if anything, suggests the opposite. Your job may be saving your life.

This article was provided by Bloomberg News. Peter Orszag is vice chairman of corporate and investment banking and chairman of the financial strategy and solutions group at Citigroup Inc. and a former director of the Office of Management and Budget in the Obama administration.