We’ve long considered loneliness and social isolation as negatively impacting our well-being. But new research published in Nature demonstrates exactly what kind of toll it can have on our bodies. Analyzing over 42,000 participants, researchers identified proteins in the blood that could be associated with self-reported loneliness or social isolation. Researchers found higher levels of these proteins in those who reported social isolation or loneliness.
The study reviewed over 2,000 different plasma proteins in blood. Researchers adjusted for age, education, income, smoking and alcohol consumption. 175 proteins were associated with social isolation and 26 proteins were associated with loneliness.
Loneliness Proteins Linked to Mortality
When you hear the word ‘protein,’ you might have a positive association. But not every protein is positive. There are hundreds of proteins associated with increased risk of diseases like stroke, Parkinson’s and Huntington’s, among others.
“We found around 90 percent of these proteins are linked to the risk of mortality,” said Dr. Chun Shen, the first author of the research, from Fudan University in China.
The proteins are associated with inflammation, antiviral responses and the immune system.
“More than half of these proteins were prospectively linked to cardiovascular disease, type 2 diabetes, stroke and mortality during a 14-year follow-up,” the study explains. None of the proteins appeared to cause social isolation or loneliness. Rather, reduced social contact and feelings of isolation causally influence protein levels. This could help scientists better understand the relationship between social contact and cancer mortality, cardiovascular disease and stroke.
In addition, researchers were able to find a small number of proteins that actually helped protect against social isolation and feeling lonely. “Only four proteins emerged as protective factors against social isolation and one against loneliness,” the report explains. “Based on the results of MR analysis, we found a significant causal relationship between loneliness and protein levels.”
