Longevity has become a space of growing interest, with many big names in tech, like Google parent Alphabet, Amazon's Jeff Bezos and Apple increasing investment into research, big data and companies trying to extend human life. It's a market that is expected to be worth at least $600 billion by 2025, according to Bank of America Merrill Lynch.
However, there may be a key to longevity that's simple and free: Optimism was found to be "associated with exceptional longevity," in a new study, and the study found that individuals who are more optimistic are more likely to live longer.
The study, published by the Proceedings of the National Academy of Sciences (PNAS), found that subjects with the most positive outlook had 50% to 70% greater odds of reaching 85 years old (considered "exceptional longevity"), compared to those who are less optimistic.
In addition, study results suggest that optimism is specifically related to 11% to 15% longer life span on average.
Both men and women with higher optimism were more likely to engage in physical activity, which researchers say could also be associated with greater longevity.
The study defined optimism as "a psychological attribute characterized as the general expectation that good things will happen." For the study, 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 surveyed 69,744 women, whom they followed for 10 years, and 1,429 men, whom they followed for 30 years.
The results of the study suggest optimism is a "psycho-social asset that has the potential to extend the human lifespan," Lewina Lee, an author of the study and clinical research psychologist at the National Center for PTSD at VA Boston said in a statement.
"Interestingly, optimism may be modifiable using relatively simple techniques or therapies," Lee said.
Although it is unclear how exactly optimism can lead to longer life, Laura Kubzansky, a senior author of the study, said it may have to do with the way optimistic people handle stress.
"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," Kubzansky said in a statement.
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