Separation stings: Study finds social isolation may cause physical inflammation

GUILDFORD, England — Cancelled weekend plans and unanswered text messages always tend to sting from a psychological perspective, but now a new study finds that days and nights spent all alone may cause us physical pain as well. Researchers at the University of Surrey and Brunel University London say that social isolation may lead to increased bodily inflammation.

As part of the largest research initiative on this subject to date, the study’s authors analyzed 30 previous studies that had explored the possibility of a connection between physical inflammation and social isolation.

“Loneliness and social isolation have been shown to increase our risk of poorer health,” says Dr. Kimberley Smith, Lecturer in Health Psychology at the University of Surrey, in a release. “Many researchers propose that part of the reason for this is because they influence the body’s inflammatory response.”

For reference, inflammation is the body’s natural way of alerting the immune system that something is up, letting it know it’s time to start repairing damaged tissue and defending against viruses or bacteria. Long-term inflammation, though, can start to damage healthy cells, tissues, and organs. This can result in a higher risk of problems like cardiovascular disease.

Regarding social isolation, it was noted that the “objective state of being isolated from other people” was associated with the occurrence of the C-reactive protein. This protein is released into our bloodstreams within hours of suffering an injury that harms tissue. Social isolation was also linked to increased levels of the glycoprotein fibrinogen, which can be converted into fibrin-based blood clots.

Interestingly, it also appears that social isolation is more likely to be harmful from a physical perspective for men than women. The study’s authors don’t have an explanation for this gender fluctuation as of yet, but say it’s probably linked to the different ways men and women deal with social stressors.

Complicating matters is the fact that the link between loneliness and inflammation isn’t as cut and dry as the findings regarding social isolation. While a possible association between loneliness and the pro inflammatory cytokine IL-6 was found in some examined studies, others saw no such connection. All in all, the research team theorize that loneliness interacts with inflammatory tendencies in the body differently than flat out social isolation.

“The evidence we examined suggests that social isolation may be linked with inflammation, but the results for a direct link between loneliness and inflammation were less convincing. We believe these results are an important first step in helping us to better understand how loneliness and social isolation may be linked with health outcomes,” Dr. Smith explains.

“Our results suggest loneliness and social isolation are linked with different inflammatory markers. This shows how important it is to distinguish between loneliness and isolation, and that these terms should neither be used interchangeably nor grouped together,” concludes Christina Victor, Professor of Gerontology and Public Health at Brunel University London.

The study is published in Neuroscience and Biobehavioural Reviews.