Negative emotions have been linked to poor health outcomes, such as heart disease and even a shorter life span. Research suggests inflammation may be responsible for this link, at least in part. The molecules involved in inflammation are essential for our body's response to infection and injury, but high levels over the long term have been linked to everything from diabetes to depression.

Few studies have assessed the health effect of positive emotions, so a team led by Jennifer Stellar of the University of Toronto (who also began studying awe in Keltner's lab at U.C. Berkeley) conducted two studies to investigate the link. In the first, 94 students completed a questionnaire to determine how often they had experienced various emotions during the past month. The scientists then took a saliva sample to assess levels of a molecule that promotes inflammation called interleukin-6 (IL-6). They found more positive emotion was associated with lower levels of IL-6.

In the second experiment, 105 students completed online questionnaires designed to assess their tendency to experience several specific positive emotions. They later visited the lab to provide saliva samples. Joy, contentment, pride and awe were all associated with lower levels of IL-6, but awe was the only emotion that significantly predicted levels using a strict statistical test.

These results do not establish whether awe actually causes changes in IL-6 levels. In fact, the authors caution that the relation probably operates in both directions: having a healthier, less stressful life may allow a person to experience more awe. They point out that awe is associated with curiosity and desire to explore, which they contrast with the social withdrawal that often accompanies illness or injury. “We know positive emotions are important for well-being, but our findings suggest they're also good for our body,” Stellar says.