What's the Latest Development?

Katherine Schlaerth, an associate professor emeritus at the U.S.C. School of Medicine, sees patients at several Southern California locations. One frustrating patient whose visits she dreaded—a retired field worker with poorly controlled diabetes and hypertension, he obstinately ignored her health advice and frequently skipped his medication rounds—made a stunning return to health after he decided to go back to work. Schlaerth's anecdotal evidence is supported by scientific studies: One completed in 2007 found retirement was associated with a steep decline in physical activity.

What's the Big Idea?

"North Americans are hardwired to consider retirement age to be 65," says Dr. Schlaerth. "Social security reinforced that idea." But perhaps working well into your autumn years will prove more boon than bust, both physically and psychologically. Not only has retirement been associated with cognitive decline, but the fact that working longer might keep you healthier should allay working Americans' fears that social security will inevitably dry up. "Increasingly, it has become obvious that the old dictum 'use it or lose it' definitely applies where humans are concerned," says Schlaerth. In this sense, young people should not worry about having to work more years.