Stress: good or bad for you? It depends. A feature in STANFORD magazine discusses immediate versus chronic stress and the effects of each on health over the long term.
From the piece:
Much of what we know about the physical and mental toll of chronic stress stems from seminal work by Robert Sapolsky beginning in the late 1970s. [Sapolsky, PhD,] a neuroendocrinologist, was among the first to make the connection that the hormones released during the fight-or-flight response—the ones that helped our ancestors avoid becoming dinner—have deleterious effects when the stress is severe and sustained. Especially insidious, chronic exposure to one of these hormones, cortisol, causes brain changes that make it increasingly difficult to shut the stress response down.
But take heart: Recent research paints a different portrait of stress, one in which it indeed has a positive side. "There's good stress, there's tolerable stress, and there's toxic stress," says [Bruce McEwen,PhD] of Rockefeller University, an expert on stress and the brain who trained both Sapolsky and [Firdaus Dhabhar, PhD].
The article goes on to describe some of the physiological effects of stress:
Dhabhar likens the body's immune cells to soldiers. Because their levels in the blood plummet during acute stress, "people used to say: 'See, stress is bad for you; your immune system's depressed,'" he says. "But most immune battles are not going to be fought in the blood." He suspected that the immune cells were instead traveling to the body's "battlefields"—sites most likely to be wounded in an attack, like the skin, gut and lungs. In studies where rats were briefly confined (a short-term stressor), he showed that after an initial surge of immune cells into the bloodstream, they quickly exited the blood and took up positions precisely where he predicted they would.
"His work was a pioneering demonstration of how important the difference is between acute and chronic stress," says Sapolsky, a professor of biology, neurology, and neurological sciences and neurosurgery. "Overwhelmingly, the bad health effects of stress are those of chronic stress."
Stanford health psychologist Kelly McGonigal, PhD, also comments in the piece that a person's view of stress plays a significant role in how stress affects him or her.
Previously: Examining the helpful and harmful effects of stress, Does more authority translate into a reduction in stress and anxiety? and Stanford’s Robert Sapolsky talks stress and the brain
Photo by Dylan Tweney
