Expect the Best and Boost Your Immune System
Having an optimistic expectation about the future can help improve your ability to fight viral and bacterial infections.
Psychological scientists from the University of Kentucky and the University of Lousiville studied 124 first-year law students over a period of six months. They were asked questions about how optimistic they felt about law school and were then injected with a material that would summon an immune response on the skin. They returned two days after each injection to have the site measured.
The skin test measured cell-mediated immunity (CMI), which plays a central role in protection against viral infections.
The students who began the semester more optimistic had more helper T-cells and higher natural killer cell cytotoxicity (the ability of the immune cells to kill cancer cells) mid-semester than those who had been pessimistic.
As the semester went by, the students’ expectations about their schooling waxed and waned, and their immune responses did as well. At more optimistic times, they would have a bigger immune system response. The response seemed to be situation specific – the belief that one would succeed at a certain goal, which normally varies over the course of a school year.
"I don't think that I would advise people that they should revise their expectations to be unrealistic," says Suzanne Segerstrom of UK. "But if people have slightly more positive views of the future than is actually true, that's adaptive…We have seen that optimism positively affects the psychological response to stressful events, and this research reflects a first step toward expanding that observation to include physical health under stress."
Past research has also tied optimism to improved immunity and better coping and disease course after a challenge such as surgery. Optimism is associated with a slower immune decline among patients with HIV, for example.
Reference: "Optimism is Associated With Mood, Coping, and Immune Change in Response to Stress"by Suzanne C. Segerstrom, Ph.D., Shelley E. Taylor, Ph.D., Margaret E. Kemeny, Ph.D., and John L. Fahey, Ph.D.; Journal of Personality and Social Psychology, Vol. 74, No. 6.