Change Your Outlook, Change Your Life

Whatever the source of their beliefs, optimists cope in ways that are generally beneficial to their health. They try to manage, reduce or eliminate the stressors or problems they face. That can produce positive effects on the immune system.

Studies show that optimists are less likely to be hospitalized after coronary bypass surgery and more likely to recover normal life function quickly, live longer after being diagnosed with various cancers and have better outcomes after undergoing angioplasty, Dr. Scheier says.

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So is the way to be healthier really as simple as putting on a happy face? Although behaving like an optimist can be good for your body in the long run, Dr. Segerstrom says it may cost a lot in the short run.

"No personality type is a magic bullet for health, and optimism has its Achilles' heel," she says. Although optimistic coping strategies help you feel happier and more able to achieve goals, "They also consume more energy than moping around," she points out, which can produce worse immune function.

"Most of the time, optimism and its typical coping style are associated with better immune function, but it's also important to recognize that that isn't always true," Dr. Segerstrom says.

Change is possible

If you're more of a pessimist, all this talk about the wonders of optimism probably isn't helping you feel better. But pessimism and optimism are really just two ways of thinking about the same thing.

"Rather than trying to change someone's expectancies for the future and their orientation to life, try to change how they cope," Dr. Scheier says. That means using more of optimism's adaptive problem-solving and less of pessimism's inaction when confronting stresses such as health problems.

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Dr. Segerstrom suggests paying more attention to the positive aspects of a situation, setting goals and learning how to achieve them.

"I have seen, over a 10-year period, that people who changed in terms of their optimism also changed in terms of their mental health and the number of days they were affected by physical health problems like pain, respiratory and gastrointestinal symptoms such as stomachache and wheezing," she says.