Health—whether psychological or physical—is characterized not just by the absence of disease but increasingly by the presence of well-being. These researchers looked at the relationship between psychological well-being (marked by optimism, happiness, and life purpose) and serum antioxidants such as carotenoids and Vitamin E, which are indicators of physical health.
While low levels of negative emotion or high levels of cardiorespiratory fitness are predictors of long-term survival in men and women, being both fit and not unhappy provides a strong combined effect, reducing premature death by 63 percent, according to this study.