According to research, those who have increased optimism, or see the glass as half full, tend to live happier lives and sleep better. Rosalba Hernandez, a professor of social work at the University of Illinois at Urbana-Champaign, headed up the multiyear study that included more than 3,500 people. The participants ranged in age, from 32 to 51, and lived in Birmingham, AL, Oakland, CA, Chicago, IL, and Minneapolis, MN. Levels of optimism were measured using a 10-item survey, and participants reported on their sleep twice in a five-year period. They rated their overall sleep length and quality during the previous month. Researchers determined that with each standard deviation increase – the typical distance across data points – in participants’ optimism scores, participants had 78% higher odds of reporting overall quality sleep. Read more about the study and results.