Staying positive through the cold season could be your best defense against getting ill, new study findings suggest. In an experiment that exposed healthy volunteers to a cold or flu virus, researchers found that people with a generally sunny disposition were less likely to fall ill. The findings, published in the journal Psychosomatic Medicine, build on evidence that a "positive emotional style" can help ward off the common cold and other illnesses. Researchers believe the reasons may be both objective as in happiness boosting immune function and subjective as in happy people being less troubled by a scratchy throat or runny nose. "People with a positive emotional style may have different immune responses to the virus," explained lead study author Dr. Sheldon Cohen of Carnegie Mellon University in Pittsburgh. "And when they do get a cold, they may interpret their illness as being less severe."