CC-licensed photo "Sneezing Man" by Mike Gifford
New research suggests that even just looking at people who are sick kicks out immune system into action. University of British Columbia scientists showed a series of images of people holding guns or photos of obviously sick folks. After the slide show, the researchers measured the levels of interlukin-6, a protein secreted by white blood cells to stimulate the immune response to trauma. From Scientific American:
Although the subjects rated the gun photographs as being more stressful than the illness images, the blood work told a different story. Whereas the gun images prompted a mere 7 percent increase in IL-6, levels of the substance were elevated 24 percent after viewing pictures of sick people."Natural Immunity: What Happens When We Simply See a Sick Person"
“It makes evolutionary sense that the immune system would respond aggressively only when it’s really needed,” says Mark Schaller, a psychologist and co-author of the study.