Abstract
There is much evidence that the relationship between religiosity/spirituality and mental health is linear and positive, but relatively few studies have included samples of non-religious participants in their analyses. Some findings suggest that, compared to people who have intermediate levels of R/S, those with higher levels and those with insignificant levels are mentally healthier. However, this curvilinear model does not appear to have been tested through a measure of spiritual beliefs and the comparison of different religious/spiritual groups. In view of this, 1788 Brazilians were assessed in terms of their spiritual beliefs, their religious/spiritual experiences, and their positive and negative mental health components. We found curvilinear relationships between R/SE and all components of mental health, but the level of spiritual belief predicted only the variance in the meaning in life. With the exception of comparisons involving happiness, at least one of the groups that had intermediate levels of R/SE had worse mental health than the groups that had the highest and lowest levels. Although religious people and atheists had similar levels of symptoms of anxiety and depression, the former presented more happiness and meaning in life. Together, these findings corroborate the curvilinear model, but suggest that R/SE is related in different ways to the positive and negative components of mental health.