One study revealed that after just 40 minutes of group singing, cortisol - the stress hormone - had fallen much more quickly than it would with the normal passage of time.
Our cortisol levels normally taper off at the end of the day but by singing, the process can be speeded up.
The act of singing causes the body to release endorphins, which are the body's feelgood chemicals and associated with pleasure.
Singing makes us take deep breaths, which in turn increases blood flow around the body and helps increase the endorphins' effect .
It's been found that we get a similar endorphin rush when we laugh, or eat chocolate.
Singing triggers the release of dopamine.
This is an important neurotransmitter that is linked to basic human biological needs.
One recent study found that we release more dopamine when we hear music which we enjoy.
The researchers also found that increased dopamine production was linked to that shiver-down-the-spine feeling we experience in response to singing pleasurable music.
Dopamine is also linked to less tangible stimulants such as falling in love.
Singers in choirs have been found to produce the hormone oxytocin.
Oxytocin is sometimes called the ‘love hormone'. We release it when we hug and it enhances feelings of trust and bonding.
This could account for why choristers experience feelings of friendship and togetherness when singing as part of a group .
Singing is an aerobic activity, and when we sing we draw more oxygen into the bloodstream, improving circulation.
Research with a Frankfurt choir showed that they produced antibodies in the blood which enhanced their immune system.