Change Your Outlook, Change Your Life

"If natural change in optimism has benefits for health, then it seems reasonable that intentional change in optimism could also help," says Dr. Segerstrom.

And the payoff could be sizable. According to researcher Becca R. Levy, PhD, associate professor of epidemiology and psychology, Yale School of Public Health, people with greater optimism and more positive views of aging have longer life spans—by as much as 7.5 years. "They have better functional health over time as well," Dr. Levy says.