Society is becoming ever more divided. But if there is one thing that’s bringing everyone together, it’s loneliness. One recent study found that nine million adults in the UK suffer from chronic loneliness: if they all moved to one city, it would be bigger than London. This isn’t just sad, it’s dangerous. Research shows that experiencing chronic loneliness is as bad for our health as smoking 15 cigarettes a day and worse than obesity. It’s associated with an increased risk of coronary heart disease and stroke, and increases our likelihood of early mortality by 26 per cent. But how can an emotional experience be so bad for our physical health?


Re-wiring the brain

Prof Steve Cole, a medicine and genomics researcher at the University of California, Los Angeles, says part of the answer may lie in the impact loneliness has on our immune system. His research shows that the cells in the immune systems of chronically lonely people change: instead of being primed to fight viruses, the cells prepare to fight bacterial infection – the kind that follows a wound or injury. This is usually a temporary state associated with the fight-or-flight response, but lonely people get stuck in it. Long term, this leads to higher levels of inflammation, which contributes to cancer, heart attacks, Alzheimer’s and depression.

When these inflammatory signals reach the brain, they change how it functions, making us more defensive and prickly, and more lonely as a result. Scientists have seen this in brain scans: in one study, lonely people’s brain activity was monitored while they were shown images of social threats, such as bullying, and non-social threats, such as sharks. The researchers found that lonely people responded faster to social threats than to other kinds of dangers. This might explain why some of us become entrenched in loneliness, as it can make social interaction harder.

40 per cent of 16-24 year olds feel lonely, yet only 27 per cent of over 75s

Our attitudes to loneliness don’t help, says Dr Farhana Mann, a psychiatrist at University College London. “People will go to their GP and tell them about whatever lesion they have, but saying they’re lonely is just too embarrassing. We need to give people a sense that it’s absolutely legitimate to talk openly about this.”

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Surprisingly, it’s younger people who seem to suffer more from loneliness. A recent nationwide survey conducted by BBC Radio 4 and the Wellcome Collection showed that 40 per cent of 16-24 year olds feel lonely, compared with only 27 per cent of over 75s.

The government is so concerned by this that from next year each department must report back on what they’re doing to tackle loneliness. That’s a step in the right direction. But in the years to come we need to find ways to help lonely people that work across the full spectrum of their experiences of the condition.

Listen to a series of All in the Mind on loneliness


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