Singing really oxygenates your blood. You stretch your lungs and take in much more air into them than before. It's really good for your health.
There are some people who walk into a room and they oxygenate it by their very being there's fresh air. Then there are those who come in with the smell of death and they suck the life out.
I believe that you should gravitate to people who are doing productive and positive things with their lives.