"A rapidly growing literature suggests that people who are deeply involved in religion tend to enjoy better physical and mental health than individuals who are less involved in religion. These findings are important because they hold out the promise of identifying alternative ways of improving the health and quality if life for people in our nation. Before this promise can be realized, at least three problems with this literature must be overcome. First, researchers have proposed many ways in which religion may affect health, making it hard to determine how the beneficial effects might arise. Second, a number of studies on religion and health has been conducted with college students, making it hard to know if the findings apply to a more representative group. Third, if religion affects health, then researchers must identify the specific physiological mechanisms that are at work. This project approaches the study of religion and health with a comprehensive battery of religion measures, a large nationally-representative sample of adults, and a range of biomarkers that can show how religion may affect physiological changes in the body. "
-The Templeton Foundation