Some people see the glass half empty, while others see the glass half full. Well, new research shows that the glass half full people will live longer than the glass half empty people. A large-scale study found those who “always look on the bright side of life” were more likely to make it to the age of 90. The trend applied across racial and ethnic groups suggests that happiness is good for the body and mind. Lead author Hayami Koga, a Ph.D. candidate at the Harvard T.H. Chan School of Public Health, believes staying positive is as good for you as exercise.

“Although optimism itself may be affected by social structural factors, such as race and ethnicity, our research suggests that the benefits of optimism may hold across diverse groups,” Koga says in a university release.

“A lot of previous work has focused on deficits or risk factors that increase the risks for diseases and premature death. Our findings suggest that there’s value to focusing on positive psychological factors, like optimism, as possible new ways of promoting longevity and healthy aging across diverse groups.”

The findings come from a review of 159,255 women in the U.S. tracked for up to 26 years. Researchers assessed their level of optimism using a questionnaire called the “Life Orientation Test” — one of the most common measures of optimism in research and practice.

The team also considered other factors such as education, marital status, income, and chronic conditions. Those ranked in the top 25 percent for optimism lived an average of 5.4 percent longer than their peers in the lowest quarter.

“Higher optimism was associated with a longer lifespan and a greater likelihood of achieving exceptional longevity overall and across racial and ethnic groups. The contribution of lifestyle to these associations was modest,” study authors write in the Journal of the American Geriatrics Society.

“Optimism may promote health and longevity in diverse racial and ethnic groups. Future research should investigate these associations in less long-lived populations.”

Growing evidence suggests positive psychological factors are connected to a lower risk of morbidity and mortality. In particular, optimism – the generalized expectation of favorable future outcomes – consistently correlates with improved health outcomes, including exceptional longevity. A sunny disposition is partly in the genes. However, experiments show that writing exercises and cognitive-behavioral strategies can inspire more optimism.

Previous research has also suggested optimistic individuals take more proactive approaches to improve their health. They are also more likely to engage in healthy behaviors such as increased physical activity, eating a more nutritious diet, and not smoking.

The new findings back to previous work; one study among mostly white American women found being optimistic led to a 15-percent longer lifespan and 50 percent greater odds of achieving exceptional longevity.

Koga concluded, “We tend to focus on the negative risk factors that affect our health. It is also important to think about the positive resources, such as optimism, that may be beneficial to our health, especially if we see that these benefits are seen across racial and ethnic groups.”