ALL IN YOUR HEAD:

Optimism was measured through questions about participants' positive experiences and expectations for the future, the study said.

"Our findings indicate that optimism has an impact on survival, whereas other studies have shown that it improves health-related functions, such as our immune systems, reducing risk factors for high blood pressure and cardiac issues, and maybe even cancer," Maaravi said.

The researchers said they looked at the participants' medical and, later, death records, and factored in parameters such as gender, economic status, marital and parental status, education levels, and physical and social activity. They also carried out one-on-one interviews over the years.

Using the data collected since the 1990s, the researchers said they have determined a direct link between a positive outlook and a longer life.

They said that participants ages 85-90 with a high optimism score had a 20% higher rate of survival over those who were less optimistic, and in the 90+ age bracket that number rose to 25%.

"Optimism doesn't have to be viewed as a trait we're born with, but one that we can develop," Maaravi said, adding that "it's important to think of ways to increase optimism because it's more clear than ever that it can help people at all stages of their lives."

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