Stress explained
Stress is what a person perceives as a threat, says Sarah Speck, a preventive cardiologist, and medical director of the Center for CardioVascular Wellness at Swedish Medical Center in Seattle. When the brain senses a threat -- even if it's a non-physically threatening one, such as a manuscript deadline or a dwindling bank account -- it tells the body to release adrenaline and noradrenaline, the fight or flight hormones. Initially, these hormones create a surge of blood to the heart and brain, which is why we get a rapid heart beat. But in the aftermath of that surge, stress hormones constrict blood vessels, which reduce the amount of oxygen getting to the heart. That makes the heart work harder, raises blood pressure, and can cause angina and chest pain.
Under stress, the brain also triggers adrenal glands to increase production of cortisol, another stress hormone. Cortisol tells the body that it is under siege, and therefore needs to hoard calories and slow metabolism to prepare for danger. Over time, this can lead to weight gain.
Not all stress, however, is unhealthy. For instance, before you're about to testify in court, the physiological changes that accompany acute stress can enhance alertness and improve certain types of memory. Adrenaline surges do improve your reaction time. Even occasional stress isn't anything to stress about. Most people can weather a storm now and then.
Psychological stress occurs any time an event exceeds an individual's perceived ability to cope, which explains why some people crumble under deadline pressure, and others rise to the occasion with grace and vigor.
"If your primary relationship is good, you're not in financial stress and one of your parents dies, it's stressful, but you don't feel out of control," says Speck. "It's when you're going through a divorce, you lose your job and a parent dies, that can feel like too much."
Acute stress takes more of a toll on a chronically stressed person than it does on a non-stressed person, says Michael Irwin, director of the UCLA Cousins Center for Psychoneuroimmunology.
That's because stress hormones that build over a long period put a strain on the heart, weaken the immune system and trigger inflammatory responses, which set off a cascade of health problems.
The trick, says Speck, is to recognize that stress is a part of life, and that chronic stress left unmanaged has harmful physical effects. You also need to recognize when your body is under stress and know what behaviors do and don't reduce the harmful effects.
For instance, when stressed, people tend to withdraw socially, eat more poorly, abuse alcohol, smoke more, get less physical activity and sleep less. But research shows that exercise, adequate rest, taking care of yourself and interacting with friends and family are among the best ways to manage stress.
-- Marnell Jameson
- Study Finds Moms Have Less Stress Oct 29, 2003
- Hear the One About the UCI Laughter Study? Nov 07, 2002
- Emotions can trigger asthma Sep 05, 2005
