HAROLD G. KOENIG
There is growing epidemiological evidence that religious beliefs and behaviors are correlated with mental health and predict both better physical health outcomes and longer survival. Exactly how religions influence physical health, however, remains an enigma. Establishing plausible biochemical and physiological mechanisms by which religion conveys its health effects is of utmost importance for advancing our knowledge about the religion-health relationship. Given the strong associations between religious involvement, social support, and stress reduction, it seems almost natural that religious beliefs and practices might affect health through neuroendocrine and immune pathways.
Studies in psychoneuroimmunology recently have shed light on the delicate and finely balanced interactions between the mind and physical body. Psychological stress, anxiety, depression, hopelessness, social isolation, and negative health behaviors such as cigarette smoking, excessive alcohol intake, and illicit drug use all have been shown to adversely affect neuroendocrine and immune system functioning. By impairing immune function, psychosocial and behavioral factors may increase susceptibility to disease or affect the course of disease once present.
Religious beliefs and practices are associated with improved coping, reduced anxiety, less depression, faster recovery from depression, greater hope and optimism, greater meaning and purpose, greater social support, and fewer negative health behaviors. Consequently, they are highly likely to influence neuroendocrine and immune function, thereby affecting physical health outcomes. Preliminary studies, although few in number and limited in sophistication, appear to support this hypothesis.