When our need for social relationships is not met, we fall apart mentally and even physically. It increasingly appears to be the cause of a range of medical problems, some of which take decades to show up, according to Psychologist John Cacioppo of the University of Chicago who has been tracking the effects of loneliness. Friendship can be the antidote to these very real ailments.

”Loneliness increases the level of cortisol (the stress hormone) in our blood, which makes us more susceptible to all sorts of health problems, including anxiety, depression and insomnia,” confirms Leaver. “Feeling excluded and lonely puts us in a state of fight or flight, which is essentially survival mode and can be really distressing.

“Friendship, conversely, can encourage the production of oxytocin, dopamine, and serotonin – all those friendly, warm, comforting hormones that support our mental health. Things like physical affection, eye contact, talking, hugging, laughing, dancing, drinking and even gossiping together are hugely bonding for human beings and all those things can absolutely help us stay happy, resilient, calm, and confident.”

But it doesn’t end there: there is evidence that friendship protects from real physical ailments as well. We have long suspected it helps our heart figuratively, but there’s actually some convincing evidence that it helps our cardiovascular health as well. In fact, Oxford University researchers found that friendship is a better pain killer than morphine!

Friendship is something you never outgrow. And believe it or not, the years friendship adds on to life can be happier ones if spent with friends. Older adults who are socially active and prioritise social goals have higher levels of late-life satisfaction, according to Medical News Today. And interestingly, the same levels of satisfaction weren’t attributed to family ‘goals’ – likely because being socially active within your family circle generally requires less physical and mental effort than it does with friends – in a good way!

In many situations friendship teaches us a lot about ourselves, often help us push ourselves out of our comfort zones while still providing a safe emotional space for us to be totally ourselves. “We know that friendship has many benefits, particularly in boosting our mental and physical health, but I’d say the most salient reason social connection is so important is really because it helps us work out who we are and who we want to be,” says Leaver.

"Good, close friends make us feel as though we belong (as do our neighbours, colleagues and more casual mates) and I cannot overestimate how vital that sense of community is for our sense of self and identity and sanity and confidence and wellbeing.”