It’s official. Researchers at the Hebrew University of Jerusalem have published the findings of their longevity study of 1200 Israelis that began in 1990. Participants aged 85-90 with a high optimism score had a 20% higher rate of survival over those who were less optimistic.

https://www.israelnationalnews.com/News/News.aspx/307287

https://academic.oup.com/biomedgerontology/advance-article-abstract/doi/10.1093/gerona/glab051/6145793