An article in Science Daily reports that loneliness does damage to the body at a molecular level.”What this 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.”

“We found that what counts at the level of gene expression is not how many people you know, it’s how many you feel really close to over time,” said Steve Cole, an associate professor at the David Geffen School of Medicine.

“We found that changes in immune cell gene expression were specifically linked to the subjective experience of social distance. The differences we observed were independent of other known risk factors, such as health status, age, weight, and medication use. The changes were even independent of the objective size of a person’s social network.”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.