In a randomized study reported in PubMed.gov in 2012 researchers studied 999 cancer patients at a cancer center between 2003 and 2008 to evaluate the effects of intercessory prayer when added to normal cancer care. Subjects completed Quality of Life and Spiritual Well Being tools at the beginning of the study and 6 months later. Subjects were prayed for over the study period. Results showed that the intervention group had significantly greater improvement over time on spiritual well-being, emotional-well being and physical well-being than the control group.
In 2012 Dr Harold Koenig and others published the Handbook of Religion and Health that documents nearly 1,200 studies done on the effects of prayer on health, Dr Koenig says traditional religious beliefs have a variety of effects on personal health. A summary of these studies shows that religious people tend to live healthier lives, are less likely to smoke, to drink, to drink and drive; and in fact, people who pray tend to get sick less often. Statistics from the 1200 studies show that hospitalized people who never attended church had an average stay of three times longer than people who attended regularly; .heart patients were 14 times more likely to die following surgery if they did not participate in a religion; elderly people who never or rarely attended church had a stroke rate double that of people who attended regularly; religious people in Israel had a 40% lower death rate from cardiovascular disease and cancer; and people who are more religious tend to become depressed less often. And when they do become depressed, they recover more quickly.