"Singing is something that many people inherently feel is good for them and relaxes them. But to actually show biologically (and demonstrate scientifically) that it can reduce stress is very exciting. The Royal College of Music team with whom we have been working has also been collecting extraordinary data working with Tenovus Choirs, seeing measurable benefits in singing among cancer patients, for example. Reducing stress has a direct benefit not only in general terms in our home lives and the workplace, but also in pain reduction, recuperation and even the advancement of some diseases."
via Health benefits of singing -- and listening to singing | Classical MPR.