After decades of research, a new study links optimism and prolonged life.

Researchers from Boston University School of Medicine (BUSM), National Center for PTSD at VA Boston Healthcare System and Harvard T.H. Chan School of Public Health, have found that individuals with greater optimism are more likely to live longer and to achieve "exceptional longevity," that is, living to age 85 or older.

Optimism refers to a general expectation that good things will happen, or believing that the future will be favorable because we can control important outcomes. Whereas research has identified many risk factors that increase the likelihood of diseases and premature death, much less is known about positive psychosocial factors that can promote healthy aging.

The study was based on 69,744 women and 1,429 men. Both groups completed survey measures to assess their level of optimism, as well as their overall health and health habits such as diet, smoking and alcohol use. Women were followed for 10 years, while the men were followed for 30 years. When individuals were compared based on their initial levels of optimism, the researchers found that the most optimistic men and women demonstrated, on average, an 11 to 15 percent longer lifespan, and had 50-70 percent greater odds of reaching 85 years old compared to the least optimistic groups. The results were maintained after accounting for age, demographic factors such as educational attainment, chronic diseases, depression and also health behaviors, such as alcohol use, exercise, diet and primary care visits.

"While research has identified many risk factors for diseases and premature death, we know relatively less about positive psychosocial factors that can promote healthy aging," explained corresponding author Lewina Lee, PhD, clinical research psychologist at the National Center for PTSD at VA Boston and assistant professor of psychiatry at BUSM. "This study has strong public health relevance because it suggests that optimism is one such psychosocial asset that has the potential to extend the human lifespan. Interestingly, optimism may be modifiable using relatively simple techniques or therapies."

It is unclear how exactly optimism helps people attain longer life. "Other research suggests that more optimistic people may be able to regulate emotions and behavior as well as bounce back from stressors and difficulties more effectively," said senior author Laura Kubzansky, PhD, MPH, Lee Kum Kee Professor of Social and Behavioral Sciences and co-director, Lee Kum Sheung Center for Health and Happiness at the Harvard T.H. Chan School of Public Health. The researchers also consider that more optimistic people tend to have healthier habits, such as being more likely to engage in more exercise and less likely to smoke, which could extend lifespan. "Research on the reason why optimism matters so much remains to be done, but the link between optimism and health is becoming more evident," noted senior author Fran Grodstein, ScD, professor of epidemiology at the Harvard T.H. Chan School of Public Health and professor of medicine at the Channing Division of Network Medicine at Brigham and Women's Hospital and Harvard Medical School.

"Our study contributes to scientific knowledge on health assets that may protect against mortality risk and promote resilient aging. We hope that our findings will inspire further research on interventions to enhance positive health assets that may improve the public's health with aging," added Lee.