A couple of months ago, researchers from Ohio State University in the United States sought to examine if the feeling of loneliness can affect the immune system in healthy subjects. To do this, they identified 200 patients who survived breast cancer and had them complete a questionnaire on the rate of perceived loneliness. They then analyzed the results of this questionnaire in relation to the results of blood drawn.
The results show that a feeling of loneliness is strongly associated with a weakened immune system, and thus, the occurrence of increased pathologies in these subjects. Researchers compare this weakness to that found in subjects living in conditions of chronic stress. They also interpret these results in that loneliness could cause a significant stress in those who feel lonely.
Article : Loneliness predicts pain, depression, and fatigue: Understanding the role of immune dysregulation. Psychoneuroendocrinology (2012)