Looking on the bright side of life could help you live longer.
Scientists say people with greater optimism are more likely to live longer and to achieve "exceptional longevity" - living to 85 or older.
Lewina Lee, assistant professor of psychiatry at Boston University School of Medicine in the US, said: "While research has identified many risk factors for diseases and premature death, we know relatively less about positive psychosocial factors that can promote healthy ageing.
"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."
The study, published in Proceedings of the National Academy of Sciences, was based on 69,744 women from the Nurses' Health Study and 1,429 men from the Veterans Affairs Normative Aging Study.
The women were aged between 58 and 86 when they completed an optimism assessment in 2004, and their mortality status was tracked through to 2014.
The men's age range was 41 to 90 when they completed an optimism assessment in 1986, and their mortality status was tracked through to 2016.
When researchers compared the participants, based on their initial levels of optimism, they found that on average the most optimistic men and women had an 11 per cent to 15 per cent longer lifespan.
They also had a 50 per cent to 70 per cent greater odds of reaching 85, compared with the least optimistic groups.
However, the researchers are unclear on how exactly optimism helps people live longer.
They point to other analysis suggesting that more optimistic people may be able to regulate emotions and behaviour, and bounce back from stressors and difficulties more effectively.
© PAA 2019
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