From boosting the brain to reducing pain, joining others in song can bring some wide-ranging benefits.

It's that time of year when the air starts to tinkle with angelic voices – or ring with the occasional lusty hymn – as carol singers spread their own indomitable brand of festive joy. All that harking and heralding. It's joyful and triumphant.

But these bands of tinsel-draped singers may be on to something. Whether they realise it or not as they fill shopping centres, train stations, nursing homes and the street outside your front door with jubilant song, they are also giving their own health a boost.

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?

"Singing is a cognitive, physical, emotional and social act," says Alex Street, a researcher at the Cambridge Institute for Music Therapy Research who studies how music can be used to help children and adults recover from brain injuries.

Psychologists have long marvelled at how people who sing together can develop a powerful sense of social cohesion, with even among the most reluctant of vocalists becoming united in song. Research has shown that complete strangers can forge unusually close bonds after singing together for an hour.

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.

There are different explanations for this. From a biological standpoint, it's thought that singing activates the vagus nerve which is directly connected to the vocal cords and muscles in the back of the throat. The prolonged and controlled exhalation involved in singing also releases endorphins associated with pleasure, wellbeing and the suppression of pain.

Singing also activates a broad network of neurons on both sides of our brain, causing regions that deal with language, movement and emotion to light up. This, combined with the focus on breathing singing requires, make it an effective stress reliever.

"The 'feel good' responses become clear in the brighter sounding voices, facial expressions, and postures," says Street.

There could be some deep-rooted reasons for these benefits too. Some anthropologists believe that our hominid ancestors sang before they could speak, using vocalisations to mimic the sounds of nature or express feelings. This may have played a key role in the development of

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