Analysis of 300,000 people in 148 studies found that loneliness is associated with a 50% increase in mortality from any cause. This makes it comparable to smoking 15 cigarettes a day, and more dangerous than obesity.
As the lead researcher of the analysis, Julianne Holt-Lunstad, comments:
Loneliness significantly increases risk for premature mortality.
Only when this shocking connection is understood will we start to treat loneliness as the public health emergency it is.
Loneliness has reached epidemic proportions in the UK, where researchers estimate that up to one in four people suffer from it. This number will certainly rise as the population ages, as more people live alone, and workplace automation further weakens bonds between people.
Cacioppo, who argued that the root cause of loneliness is evolution, pointed out that modern society is worlds away from the community-based life for which we are designed. Humans are such deeply social animals that it makes no more sense to consider a person in isolation than it does an ant or a bee. Even as adults, we are so dependent on our groups that for millennia, separation from them was a de facto death sentence.
For this reason, said Cacioppo, we evolved to experience social rejection in the same way as physical pain. Brain scans have shown that “social pain”, such as being shunned by a community, activates the same region – the dorsal anterior cingulate – as bodily trauma.
When we feel threatened by isolation, evolved responses drive us into a state of cognitive hypervigilance. We voraciously scour situations for social information that might allow us to reestablish personal connections.
Tragically, though, the very same hyper-alert state creates characteristic errors in social thinking that make us negatively misinterpret the information we detect. When we are lonely, we tend to misread others’ intentions as critical, competitive or threatening. We are less able to imagine things from their perspective.