Why do we need stress to survive? We need stress to get out of bed in the morning and to stay focused. But when the brain thinks we're being threatened, the physical response is big. Breathing accelerates, heart rate and blood pressure rise, and blood vessels in the skin constrict so that if we're injured we won't bleed as much, writes Bruce McEwen, author of "The End of Stress As We Know It," and head of the neuroendocrinology lab at Rockefeller University in New York. Infection-fighting white blood cells rush to the ready and the body releases glucose to mobilize the body. When the perceived or real danger passes, the body begins the complex process of calming down.

Stress bite: Massage therapy at Bodiwerks in West Seattle has been up by more than a third since Sept. 11, 2001, according to founder Megan Caddy, who saw a further increase when the war in Iraq began.

Interesting stress facts • Even moderate noise can add to heart-damaging stress hormones, according to a Cornell University study, because hearing is improved during times of stress. • Women who suffer chronic stress have lower bone density, according to a 1996 study. • A University of California study showed that the stress hormones released by a pregnant woman can make her baby more prone to stress and heart attacks. "That the stress-response itself can become harmful makes a certain sense when you examine the things that occur in reaction to stress. If you experience every day as an emergency, you will pay the price." -Robert Sapolsky, Stanford University professor and biologist, author of "Why Don't Zebras Get Ulcers?" "The best way to deal with stress is by maintaining our physical and emotional health. This means taking a long, hard look at lifestyle." -Bruce McEwen, Author of "The End of Stress as We Know It"

What's wrong with that? Nothing, if we're trying to leap from a runaway car or meet a quick deadline. But if we get flooded with the stress hormones adrenaline and cortisol every time we deal with impossible workloads, traffic jams or anything else that we can't control, our defenses begin to turn on us. The body loses its ability to go back to a baseline calm.

Stress bite: More power to control your destiny, less stress. British Civil Service public servants on the second-highest rung had disease rates twice as high as those at the very top. Those at the bottom of the hierarchy were four times higher.

What can happen to our health? Plenty. Diabetes, depression, heart disease and rheumatoid arthritis are among the diseases linked to stress. If those surges in blood pressure that we get from adrenaline are repeated over and over, they can damage our blood vessels, leading to atherosclerosis, in which pockets of fatty deposits cause the coronary arteries to clog. Wonder why you still have that potbelly even if you're otherwise thin? High levels of the hormone cortisol and increased glucose in the blood send fat to the waist for storage instead of the thighs or bottom. That's great if food is in short supply, but otherwise it adds to the risk of heart disease and cancer. And then there's our memory. In times of acute stress, hormones help us remember that this is where the danger happened, which gives us a chance to avoid it next time. But if the stress just keeps coming, brain cells begin to shrink, memory becomes impaired and we start to generalize our fear or anxiety, failing to associate time and place. We're worried about something, but what?

Stress bite: Acute stress boosts the immune system, while chronic stress causes wear and tear. Doctors found that small wounds took an average of nine days longer to heal in women who cared for patients with Alzheimer's disease than in women who were not under similar stresses, according to an Ohio State University study.

Stress bite: Treat your children well. Cuddled newborn animals produce lower amounts of cortisol in response to stress than animals that have less physical contact, according to a Canadian study.

How can you find better balance?

• Watch what you eat and when you eat. Large meals elevate the stress hormone cortisol. And large, fatty meals eaten late, when the liver is especially susceptible, can send more bad fats to the midriff for what the body thinks is important storage.

• Increase your social circles. More than 10 studies show that people who have good social support have a lower risk of death over a defined period of time. Good relationships remind people that there are other aspects of life more important than whatever is causing grief, McEwen says, and they can give people the confidence to leave a bad relationship or job.

• Resist the demands on your time. Don't take calls from the office or check your messages on weekends, McEwen says.

• Follow your grandmother's advice: Exercise regularly, eat healthful food and get a good night's sleep, which is nature's best tool for restoring yourself. It's not easy to sleep if you're stressed, but don't compound it by staying up too late (even to finish projects).

• Monitor the information you take in. The Blue Mountain Center of Meditation and Nilgiri Press suggests that you pick your favorite way to keep informed and entertained and limit yourself to just that (which many people wish they'd done during 9/11 and the Iraq war). If you get onto a topic or conversation you know will make you agitated, ask to change the topic, or walk away.

• Find what works to keep you calm, which could be meditation, deep breathing, yoga or just going for a walk. Exercise is not only a great stress reducer but it encourages a sense of well-being.

• If you're feeling stress at home, the University of California's Wellness Guide suggests that you make a list of what bothers you and start working on one thing you might be able to change.

Sources: "The End of Stress as We Know It," Bruce McEwen, Joseph Henry Press; "Why Zebras Don't Get Ulcers," Robert M. Sapolsky, W. H. Freeman and Company; The Foundations of Wellness, University of California at Berkeley; "Stress, the mystery factor of health?" Australian Broadcasting Corporation; The New York Times Science Desk; National Public Radio, The Times Union (Albany, N.Y.).

Sherry Stripling: sstripling@seattletimes.com.