I've been reading a recent review in a medical journal called Primary Care Clinics entitled "Role of the Social Milieu in Health and Wellness." It reviews what's known about the relationship between health, spirituality (by which they appear to mean religious observance, although I disagree with that), economic status, and educational level. It's long been known that poor people get sicker more often and die sooner than do rich people, but the interesting aspects of the article to me were about religion and spirituality. I can't link the article because you need a subscription, but I have a pdf file of it I'll gladly send to anybody who's interested. Here are some highlights:
  1. A study of 21,000 adults showed that persons who never attended any religious exercises at all had a 19-fold higher risk of death over the 8 year period of the study.
  2. A meta-analysis (a way of combining many studies) of both Judeo-Christian and Eastern traditions showed decreased levels of stress hormones and harmful blood cholesterol, as well as overall improved health.
  3. Meditation (which need not be a religious exercise, of course) causes increases of useful neurotransmitters in the brain.
In fairness, several studies showed negative stress effects for religious observances that were characterized by heavy criticism of those who deviated from strict practices -- no surprise there.

The question is, of course, what precisely is this "religion" being studied? Here are the authors' conclusions:

"A straightforward explanation of religion’s health effects might be as simple as religious participation encouraging better health habits, social support, self-esteem, and self-efficacy. Spirituality is negatively correlated with drug use. Stress or, more accurately, an individual perception of stress has a significant impact on health through modulation of cardiovascular and immune system primarily through alteration of the sympathetic nervous system. Religious or spiritual beliefs and practices are related to well-being, hope, optimism, purpose, meaning, and social support. Through reduction in stress perception, spiritual practices result in reduction in heart disease, hypertension, morbidity, and mortality and improve immune and endocrine function."