Having an optimistic view on life might strengthen your immune system’s ability to fight infections, suggests a study published in Psychological Science and reported by HealthDay News.

The findings add to existing evidence linking people’s attitude to how well their immune system functions to ward off disease. Specifically, a person can “have different immune functions when he or she feels more or less optimistic,” said study author Suzanne C. Segerstrom, PhD, a professor in the department of psychology at the University of Kentucky.

For the four-year study, researchers from the University of Kentucky gave surveys with questions about optimism and school success to 124 first-year law students.

Participants also received an antigen injection that makes the immune system create a lump on the skin (a bigger lump meant a stronger immune system reaction).

Researchers found the immune response became more powerful in students who were more optimistic over time and weakened when they became more pessimistic.

But the findings leave room for the effect of other factors that can contribute to immunity fluctuations, Segerstrom said.

“When people felt more optimistic, they also felt more happy, attentive and joyous, and that accounted for some of the relationship between optimism and immunity,” she explained.

James E. Maddux, PhD, a professor of psychology at George Mason University, not affiliated with the study, added, “It’s hard to make any firm conclusion from a single study, but it’s one more piece of evidence that what we think actually matters in some very important ways.”

What does this all mean for you?

Hilary Tindle, MD, a researcher at the University of Pittsburgh Center, has a few theories.

One of Tindle’s theories is that happier or more positive people react in healthier ways to stress, which quickens their recovery from illness.

The other is that more positive people are more likely to stick with medical treatments and heed doctors’ advice.

In a previous study, Tindle found that optimism had a positive effect on women’s hearts and longevity.

“Optimistic women had more stable risk profiles with less high blood pressure and diabetes,” Tindle said.
Read about what optimism can do for your heart here.