For seven years, Joe Gagliardi, a programming manager for Southeast Frozen Foods, worked in what felt like a sick ward.

Everybody was constantly ill, though Gagliardi fared better than most. "There were always colds, sneezing, temperatures and a lot of sick days," he says.

The programmers worked in a separate building (no, not a freezer) so some became convinced that it must be the building making them sick. What else would explain it?

A programmer called the Centers for Disease Control and Prevention, and eventually the company hired some environmental consultants to investigate.

The consultants came. They sampled the air and the water, looking for poisons and pollutants. They sniffed the rugs and peered into the air-conditioning ducts, looking for viruses and bugs.

They didn't find anything.

Five and a half years ago, Gagliardi left that job to become CIO of Unisa, a distributor of women's shoes and accessories.

And he got better.

So maybe the consultants had missed something.

Or maybe all the coughing and sneezing and fevers had something to do with the fact that Gagliardi and his fellow programmers regularly worked long weeks and 12-hour days. Most of Gagliardi's colleagues eventually quit, until it was just him and a woman who started the same time he did.

As he's talking about this, Gagliardi has an epiphany. "My God," he says. "I realize now that thats why we were sick all the time.

"It was the stress."

The Stress Epidemic
Only in the past 20 years or so has science arrived at the same conclusion as Gagliardi. The New England Journal of Medicine in 1998 went so far as to declare that "managing the long-term effects of the physiological responses to stress is critical to survival." Stress may contribute to 85 percent of all medical problems, says Connie Tyne, executive director of the Cooper Wellness Program in Dallas, which counsels executives on stress reduction. Fifty-two percent of executives will die of diseases related to stress, according to Tyne. That's partly because stress affects nearly every major system in our bodies, creating a laundry list of health problems—among them diabetes, high blood pressure, stroke, allergies, asthma and colitis.

The clearest sign that there's a stress epidemic can be seen in heart disease statistics. For example, a recent study found that people who get less than five hours of sleep twice a week or more are 300 percent more susceptible to heart attacks. Their overall rate of developing heart disease doubles.