The pressures of daily life—jobs, relationships, money, raising children and now, war and terrorism—have become such constant companions that many of us operate with ever-present feelings of pressure, anxiety or burnout. We may try to ignore its presence, but it doesn't go away. It just goes to work inside the body.
Prolonged stress contributes to many physical and psychological ills:
- It overrides natural defenses against viruses that cause AIDS, chickenpox and the common cold.
- It encourages the production of inflammatory hormones that drive heart disease, obesity and diabetes.
- It sparks flare-ups of rheumatoid arthritis and digestive disorders.
- It creates depression and ages the brain.
A vital tool for survival for humans, it is the body's response to life-threatening situations and in the days when our ancestors either had to outrun the lion or kill it. According to Stafford Lightman, an endocrinologistat Bristol University, England, in order to get away you need to give as much oxygen and as much sugar to your muscles to make them work as fast as they can, so your blood flow needs to go faster.
When you're being frightened, your brain detects the danger, it sends signals down your spinal cord to your adrenal medulla to release the stress hormones epinephrine and norepinephrine (also called adrenaline and noradrenaline). The adrenaline increases the amount of sugar in your blood and increases your heart rate, and this helps your efficiency of getting away from the lion.
Your brain also sends signals down to the pituitary gland, which releases another hormone which acts on the outside of the adrenal, the adrenal cortex, and that releases cortisol. Cortisol is also very important in keeping your blood sugar up, keeping your blood pressure up, and helping allow the body to have maximal exertion to get away from danger.
But in chronic stress, the body is flooded with epinephrine and norepinephrine, regardless of whether there's a threat, allowing bacteria, viruses or tumors to flourish and making blood more prone to clotting.
There's also excess of cortisol, promoting the accumulation of abdominal fat, suppressing immunity, shrinking brain cells and impairing memory.
Scientists are only now beginning to understand what happens when stress disrupts the delicate interplay between the brain, the endocrine system—the glands and organs that make and release hormones -- and the immune system, stimulating the release of compounds that cause inflammation.
They're beginning to identify ways to stop this inflammation and other stress-related biological effects, too.
Recent research has identified some of the following ways in which stress influences the course of illnesses linked to viruses, aging or the body's misguided attack on its own tissues.
Physical or mental stress can take an enormous and sometimes deadly toll on the heart. It increases blood pressure, narrows blood vessels and causes blood to become stickier and more likely to clot, increasing the likelihood of a heart attack or stroke.
"New treatments that teach us ways to relax and cope with daily stress offer great promise in decreasing the risk for many preventable illnesses," noted Dr. Michael Irwin, director of the Norman Cousins Center for Psychoneuroimmunology at UCLA's Neuropsychiatric Institute.
Recent research has identified some of the ways in which stress influences the course of illnesses linked to viruses, aging or the body's misguided attack on its own tissues.
- Physical or mental stress can take an enormous and sometimes deadly toll on the heart. It increases blood pressure, narrows blood vessels and causes blood to become stickier and more likely to clot, increasing the likelihood of a heart attack or stroke.
In February, Irwin published a study in the American Journal of Psychiatry showing that stress and depression in heart attack patients increase amounts of chemicals that make certain immune cells sticky and help them travel to artery linings, where they produce inflammation and promote coronary artery disease.
A study published in the journal Circulation found that mental stress also triggers irregular heartbeats, which can be deadly.
- Stress can certainly give you butterflies or a stomachache, but chronic stress can trigger flare-ups of irritable bowel syndrome, an intestinal condition that includes cramping, gas, diarrhea and constipation.
- Although stress is no longer believed to cause ulcers (they're sparked by an infection of the bacterium H. pylori), it can worsen symptoms.
- HIV-infected gay men who keep their sexual orientation secret get sicker and have shorter life spans than gay men who are more open about their sexuality, a 1996 study found. Closeted gay men tend to be shyer and their nervous systems overreact to stress; as a result, their bodies pump out more stress hormones, which encourage the virus to multiply.
Steve Cole is an assistant professor of medicine at UCLA who conducted the 1996 study as part of his research into how disease-causing organisms respond to stress.He further reported in the December 2003 issue of Biological Psychiatry that these more stress-sensitive men had higher levels of the AIDS virus in their blood and didn't respond as well to AIDS drugs.
Cole and his colleagues found that an excess of stress hormones makes it easier for HIV to get into cells and reproduce more quickly, while suppressing production of chemicals that would protect cells from the invasion.
- People who suffer from autoimmune disease of the joints already have high levels of hormones called inflammatory cytokines, which cause swelling,pain and inflammation. Stress and depression, which can intensify pain and create more physical limitations, further increase those levels, according to a study in the March issue of the Journal of Rheumatology.
Meditation and Medication
As their understanding of the biochemistry of stress increases, scientists are developing and testing ways to protect the body from its ravages, using yoga and meditation, psychotherapy and medications, and even experimental devices.
Among the simpler interventions that hold the most promise is tai chi, a centuries-old Chinese exercise often described as "meditation through movement."
Drug therapy can also be used to counter stress. For example, Cole and his colleagues have just started a study in which they're giving beta blockers, which are typically prescribed for hypertension and heart disease, to HIV patients. The drugs should block the ability of stress hormones to make HIV multiply, the researchers say, thus lowering viral loads.
Other medications, such as antidepressants and anti-anxiety drugs, alter the brain biochemistry that makes some people overreact to stress.
Other treatments ranged from vagus nerve (controls involuntary functions such as heart rate, respiration, digestion and bladder function) stimulation to delivering electromagnetic waves through a device placed against the roof of the mouth, to treat anxiety attacks and other manifestations of chronic stress.
Dr. Paul Rosch, president of the American Institute of Stress in Yonkers, N.Y, warned however that each case is different from the next one and there is no stress-reduction cure all.