The downside of stress has been well documented by data that links it to many health conditions including depression, heart disease, and gastrointestinal disorders. Long-term stress is also thought to weaken the immune system and increase vulnerability to infections.
But a new report says that in certain situations stress may actually boost the immune response. In the study, which was published in the September – October issue of the journal Psychophysiology, researchers evaluated the effects on the immune system of two stressful situations that were chosen because they were expected to trigger different physiological effects.
In one of the tasks, volunteer students memorized a series of letters and then took a test; in another they had to passively endure watching a “grisly” video. In the first instance, the heart rates of the volunteers increased as expected, and they showed a strengthened immune response. When the study participants watched a highly disturbing oral surgery video, their heart rates decreased, and their immune system was suppressed.
“Stress has a bad reputation as being something that can make you ill, but under certain circumstances, stress can be very good for you,” says lead author Jos A. Bosch, postdoctoral fellow in oral biology at Ohio State University. “It is a natural adaptive response that prepares your body and mind to fend off danger, but it’s important to have an outlet, a way of responding to the stressor.”
Bosch says that the research, which was done together with scientists at the University of Amsterdam, helps explain why meeting deadlines or other work challenges that call forth a “flight or fight” response might help shore up our body’s defenses, whereas seeing an accident in which someone is severely injured or dies and being unable to do anything about it might weaken our ability to fight off disease. The report may also help explain why people seek thrills like watching scary movies, playing video games, and bungee jumping.
In the study, researchers presented 34 male undergraduates with stressful experiences and then analyzed the concentration of a certain immune factor called S-IgA–which stands for secretory immunoglobulin A–in saliva samples of the subjects. The data showed that the concentration of this immunoglobulin, which is the body’s first line of defense against pathogens, increased during the memory test but decreased when the volunteers watched the gruesome video.
Although the two tasks studied were both stressful, they give important clues about nuances of stress and how our bodies respond. “It has been thought that most negative tasks would involve a weakened immune response, but the nature of the tasks and the emotions they evoke may make a difference, ” says Arthur Stone, PhD, professor and vice chair of the Department of Psychiatry at SUNY Stony Brook Medical School. “It’s possible that when something is negative, but challenging, it could be a stimulant.”
Article By: Joyce Baldwin, Medical Writer