Do you have stress—or does stress have you?

Chronic stress is described by the American Psychological Association (APA) as “the stress of unrelenting demands and pressures for seemingly interminable periods of time.” It’s the ever-mounting, everyday tension that has become of symptom of modern life. The APA further notes that “stress is linked to the six leading causes of death: heart disease, cancer, lung ailments, accidents, cirrhosis of the liver and suicide.”

Stress correlates with these and dozens of additional medical conditions—from a ringing in the ears to ulcers, stroke and even AIDS—because it compromises the immune system, increasing susceptibility to illness. Among the most compelling evidence of this is a landmark study from 1991 by Sheldon Cohen, a psychologist at Carnegie Mellon University, who exposed subjects to viruses that cause the common cold. He found that the frequency and severity of colds were directly related to the amount of stress the subjects reported.

Read the APA’s description of different kinds of stress here.

It is well known that an acutely stressful situation can precipitate a brief spike in blood pressure. However, the assumed link between job stress and chronic high blood pressure, or hypertension, has been called into question. In an article published in the May 2006 issue of Current Hypertension Reviews, Dr. Samuel J. Mann of Cornell University stated that “after decades of research, the evidence for a relationship between job stress and blood pressure is weak.” Mann reviewed 48 studies involving more than 100,000 subjects and found the results too inconsistent to identify job stress as a dominant and direct cause of sustained high blood pressure. Now, stress at work may lead to problems such as overeating, weight gain, or alcohol abuse — all of which increase the risk of high blood pressure. But these are indirect causes, whereas Mann addressed the direct relationship between pressure in the office and pressure in the bloodstream.

“There’s nothing you can say about stress that’s generic or applies to everybody,” says Dr. Paul J. Rosch, president of the American Institute of Stress. For instance, deadlines at work may be daunting for one person while the pressure spurs creativity in another. One mother may regard a baby’s cry as beautiful and life affirming while the sound literally drives another to drink. Dr. Rosch explains that people manage identical situations differently using the analogy of a roller coaster ride. “Some of the people are in the back seats with their eyes shut, jaws clenched, and they can’t wait for the ride to end. But up front you have the wide-eyed thrill-seekers yelling and relishing every steep plunge—they race to get on the very next ride. And in between you might find a group for whom the ride was just boring. So, was the roller coaster ride stressful?”

As described in the roller coaster scenario, stress is perception. What distinguished the people in the back from the people in the front was the sense of control they perceived. Stress is all about the subjective response to loss of control.

That’s not to say a mortgage payment, a traffic jam or Thanksgiving dinner with the extended family doesn’t present a real problem. The way stressful circumstances are ultimately perceived and managed determines whether they adversely affect your health.

There’s no sure-fire exercise that reduces stress in everyone. When seeking any stress-reduction technique, pay attention to what promotes the therapeutic response you seek. A physiological result of healthy exercise is the release of endorphins, which reduce pain in the body and counter the effects of hormones identified with stress. But while one person benefits from the endorphin release following an aerobic workout, another may be soothed by the rhythmic movement of a rowing machine, and another may simply enjoy the escapism of wearing headphones while walking around the block. Others engage in group sports and activities, supporting the widely held theory that social interaction is an excellent stress buffer.