© 2004 Newsweek, Inc. - Sept. 27 issue

Scientists are mapping the pathways that link emotion to health. The challenge for the rest of us is to put these discoveries to work. By Herbert Benson, M.D., Julie Corliss and Geoffrey Cowley.

Imagine you're allergic to the oil of the Japanese lacquer tree - so allergic that the brush of a leaf against your skin provokes an angry rash. Strapping a blindfold over your eyes, a scientist tells you she'sgoing to rub your right arm with lacquer leaf and your left arm with the innocuous leaf of a chestnut tree. The rubbing commences, and before long your right arm is covered with burning, itchy welts. Your left side feels fine. No surprise, until you learn that your left arm - not the right - is the one that got lacquered.

Or imagine that Parkinson's disease has reduced your walk to a shuffle and left your hands too shaky to grasp a pencil. You enroll in a study and receive an experimental surgical treatment, which dramatically improves both your gait and yourgrip. You're ready to declare it a miracle of modern medicine, when you discover that the operation was a sham. The surgeons merely drilled a small hole in your skull and then patched it

"... the relationship between emotion and health is turning out to be more interesting, and more important, than most of us could have imagined." That thoughts and feelings can affect our health is hardly news. In the span of a few decades, mind-body medicine has evolved from heresy into something approaching cliche.

So why is NEWSWEEK devoting this Health for Life report to the mind-body connection? Because the relationship between emotion and health is turning out to be more interesting, and more important, than most of us could have imagined.

Viewed through the lens of 21st-century science, anxiety, alienation and hopelessness are not just feelings. Neither are love, serenity and optimism. All are physiological states that affect our health just as clearly as obesity
or physical fitness. And the brain, as the source of such states, offers a potential gateway to countless other tissues and organs-from the heart and blood vessels to the gut and the immune system. The challenge is to
map the pathways linking mental states to medical ones, and learn how to ravel them at will.

"Modern life is rife with potential stressors, and there is now little question that uncontrolled stress can kill."

According to a recent government survey, nearly half of all Americans used mind-body interventions in 2002. The respondents embraced practices ranging from deep breathing and progressive muscle relaxation to meditation, hypnosis and guided imagery. Close to half of them also said they prayed-perhaps the oldest and most basic form of mind-body medicine.

They had plenty to pray for. Modern life is rife with potential stressors, and there is now little question that uncontrolled stress can kill. Harvard physiologist Walter Cannon recognized 90 years ago that when confronted by a threat-physical or emotional, real or imagined-the body responds with a rise in blood pressure, heart rate,
muscle tension and breathing rate. We now know that this physiological "stress response" involves hormones and inflammatory chemicals that, while valuable in measured bursts, can foster everything from headaches to heart attacks in overdose. Cannon verified that people who believed they'd been hexed by voodoo witch doctors could drop dead from a sudden and massive stress response. We now know that chronic stress, though not
always fatal, can disrupt the digestive system, worsen symptoms of menopause and interfere with fertility. Indeed, experts now believe that 60 to 90 percent of all doctor visits involve stress-related complaints.

As researchers chart the health effects of hostility and hopelessness, they're also gaining unprecedented insights into the mind's power to heal. The "placebo response" has been widely recognized since the 1950s, when Harvard's Dr. Henry Beecher described the phenomenon. Until recently, most experts dismissed it as a feat of self-deception, in which people who remain sick (or never were) convince themselves they're better. But we're now discovering that expectations can directly alter a disease process.

Consider those Parkinson's sufferers who improved with sham surgery. Using PET scans, researchers compared their brains with those of patients who received an active treatment. As expected, theactive intervention caused a significant rise in dopamine, the neurotransmitter that people with Parkinson's lack. But the patients who
improved on placebo experienced a similar dopamine surge. A related study found that fake analgesics could boost the brain's own pain-fighting mechanisms. In both cases, the placebo response was not an
imaginary lessening of symptoms but an objective, measurable change in brain chemistry.

Placebos are just the beginning. Mounting evidence suggests that any number of soothing emotional experiences can improve our physical health. At Duke University, researchers have found that religious observance is associated with lower rates of illness an hospitalization. In studies of HIV-positive men, researchers at UCLA
have found that optimism is associated with stronger immune-cell function. And research at Harvard suggests that the "relaxation response"-the deep sense of calm we can achieve through yoga, prayer or simple deep-breathing exercises-can help counter the effects of chronic stress. We now believe that the body produces more nitric oxide when deeply relaxed, and that this molecule acts as an antidote to cortisol and other potentially toxic stress hormones.

Can we teach ourselves to be healthier? That is the central question of mind-body medicine, andthe answer is not an unqualified yes. Stressful life circumstances are sometimes inescapable (no one chooses poverty or discrimination).

"Yet mind-body techniques can improve almost anyone's quality of life." Heredity and temperament leave some of us more stress-prone than others. And prayer is clearly no substitute for penicillin or a decent diet. Yet mind-body techniques can improve almost anyone's quality of life. Meditation may not cure cancer, but by alleviating fear and softening the side effects of treatment, it leaves many patients feeling less victimized. Stress-related illness often defies conventional remedies, and when we persist with high-tech pills and procedures, the costs of treatment can easily outweigh the benefits. Mind-body medicine offers a saner starting place. If it fulfills half its promise, it could reduce medical costs while improving our health and our lives. And whatever its limitations, it has the advantage of doing no harm.

Benson is the Mind/Body Medical Institute Associate Professor of Medicine at Harvard Medical School and founding president of the Mind/Body Medical Institute in Boston. CORLISS is a medical writer at Harvard Medical School. Cowley is NEWSWEEK's health editor. For more information go to health.harvard.edu/NEWSWEEK.