Research shows that whether a person is an optimist or a pessimist is related to their quality of life, including their physical health. The subjects involved first personality tests in the 1960’s and then thirty years later they completed a follow-up self-assessment of their health status. Researchers found that not only did the optimists from the 1960’s report better physical and mental functioning thirty years later, but that optimists also lived longer on average than pessimists.