Researchers have known for many years that a person’s social environment can affect their health. Those who are socially isolated—that is, lonely, tend to suffer from higher mortality than people who are not. But a new study shows how loneliness actually acts like a physical element of some kind on the genes and activity of the human body.
In this first study of its kind, from the current issue of the journal Genome Biology, UCLA researchers have identified a distinct pattern of gene expression in immune cells from people who experience chronically high levels of loneliness. The findings suggest that feelings of social isolation link to alterations in the activity of genes that drive inflammation, the first response of the immune system.
This important research provides a framework for understanding why social factors are linked to an increased risk of heart disease, viral infections and cancer. It appears that loneliness is actually a physical attack on the body.
It has been previously established that lonely people suffer from higher mortality than people who are not. “What this new study shows is that the biological impact of social isolation reaches down into some of our most basic internal processes, the activity of our genes.” said Steve Cole, an associate professor of medicine at UCLA.
“We found that changes in immune cell gene expression were specifically linked to the subjective experience of social distance,” said Cole. "The differences we observed were independent of other known risk factors, such as health status, age, weight, and medication use.”
Cole and colleagues at UCLA and the University of Chicago found genes overexpressed in lonely individuals included many involved in immune system activation and inflammation. But interestingly, several other key gene sets were underexpressed, including those involved in antiviral responses and antibody production. These findings show direct evidence of the adverse health effects of social isolation.