From BBC:
From the brain to the heart, singing has been found to bring a wide range of benefits to those who do it, particularly if they do it in groups. It can draw people closer together, prime our bodies to fight off disease and even suppress pain. So might it be worth raising your own voice in good cheer?
Perhaps unsurprisingly, there are clear physical benefits for the lungs and respiratory system from singing. Some researchers have been using singing to help people with lung diseases, for example. (Read more about why your lungs provide an important signal of how you are ageing.) But singing also produces other measurable physical effects. It has been found to improve people’s heart rate and blood pressure. Singing in groups or choirs has even been found to boost our immune function in ways that simply listening to the same music cannot.