Don't try telling Dr. Sanjay Gupta that being a workaholic is bad for your health.

A professor, practicing neurosurgeon, Time magazine health columnist, and chief medical correspondent for CNN, he works 15 hours a day and travels at least one week out of every month. "I happen to have two professions that are both unpredictable and have high demands," says Gupta, who normally rises at 5:30 a.m. each morning and operates on patients in the evenings and on weekends.

When he's not on air, teaching at Atlanta's Emory University School of Medicine, or in surgery at Grady Memorial Hospital, Gupta, 37, spends time with his wife and two daughters. Along the way, he's managed to write his first book, Chasing Life. Published earlier this month, it highlights new research on living longer and healthier.

So where is the clich�d workaholic-bleary-eyed; prone to headaches, stress, and heart disease; toiling in self-imposed solitary confinement-in this picture? According to Gupta, extremely long work hours don't necessarily add up to bad health. "You can be a workaholic and have outstanding health," he says. "People who are workaholics derive a sense of purpose from their work and activities, and [that can] release feel-good hormones that mediate blood pressure, regulate heart rate, and decrease stress."

Gupta isn't the only doctor giving workaholics a clean bill of health. "Believe it or not, their health problems are the same as other people's. They don't get cancer or heart disease because they're workaholics," says Dr. Christian LeFevre, a physician affiliated with MDVIP, a private health-care company that limits its patient-to-doctor ratio, allowing for more personalized treatment. LeFevre is located in Washington, and works with executive-level government officials, lobbyists, and airline execs.

In 1989, Bill Marriott, chairman and C.E.O. of Marriott International, suffered a series of heart attacks due to a lifestyle heavy on unhealthy meals and light on exercise. Since then, he has modified his calorie intake, reduced late-night dinners, taken up Pilates, and incorporated daily treadmill sessions. The one thing the 75-year-old self-proclaimed workaholic hasn't done is cut back his hours at work. Marriott logs 90 travel days a year and 60- to 70-hour workweeks. "It's good for your health," says Marriott. "My work makes me very happy."

Unfortunately, that's not true for everyone. According to two long-standing medical studies, what really harms health isn't the number of hours spent hunched over a proxy statement, but the amount of perceived control workers feel they have over their jobs-and their position in the office hierarchy.

In a series of studies, Whitehall I and Whitehall II, Sir Michael Marmot, professor at University College London and author of The Status Syndrome, looked at mortality rates of employees in the British Civil Service, a highly stratified working environment, and found that those with the lowest rank had a mortality rate three times higher than those highest up.

"When we started the study, in the '70s, everybody thought that stress caused heart attacks and was more common in business executives and people at the top of the hierarchy," says Marmot. "That was the conventional wisdom. What our study showed was a very clear gradient, stepwise: The lower you were, the higher the mortality from heart disease and other diseases."

Marmot has no trouble explaining the results. "People in high-status jobs have more demand on them, and more to do, but also more control. And having low control over the job predicted heart disease, mental illness, absence from work, and back pain."

Not only does Gupta have control over his jobs, he enjoys them. And maybe that's the secret. "Loving your job is a large part of it," he says. "People say a change of activity is a form of rest. When I go from neurosurgery to writing a column on aging, it lets other neurons in the brain rest." In that case, the hardest-working executives with the most varied schedules may be giving their neurons more rest than anyone else.

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