“John Cacioppo, a social psychologist at the University of Chicago in Illinois, studies the biological effects of loneliness. In a steady stream of recent papers, he and collaborators have identified several potentially unhealthy changes in the cardiovascular, immune, and nervous systems of chronically lonely people. Their findings could help explain why socially isolated people have shorter life spans and increased risk of a host of health problems, including infections, heart disease, and depression. Their work suggest that it’s the subjective experience of loneliness that’s harmful, not the actual number of social contacts a person has. “Loneliness isn’t at all what people thought it was, and it’s a lot more important than people thought it was,” Cacioppo says.” Greg Miller, “Social Neuroscience: Why Loneliness Is Hazardous to Your Health,” Science 331: 138-140, 14 January 2011.
A 1988 Science paper suggest that social isolation increases mortality, and an analysis of 148 previous studies, published in the July 2010 issue of PLoS Medicine, suggests that social isolation increases the risk of death about as much as smoking cigarettes and more than either physical inactivity or obesity. Loneliness is a health risk on its own, apart from conditions such as depression or stress that are common fellow travelers. Cacioppo’s works show that the subjective experience of loneliness that’s important for people’s well-being rather than any objective measure of social connectivity (the number of close contacts someone has, for example). Daniel Russell, a psychologist at Iowa State University in Ames, says that “some people are socially isolated and they’re not lonely; by contrast, some people are lonely even if they have a lot of social contacts.”
Evidence that loneliness is partly heritable has emerged from a collaboration between Cacioppo and Boomsma. Overall, the heritability of loneliness is comparable to that of depression, Boomsma says, but less than that of traits such as high blood pressure and cholesterol levels. In his 2008 book, Loneliness: Human Nature and the Need for Social Connection, Cacioppo hypothesizes that there is a “genetic thermostat” for loneliness that’s set differently in different people. That setting determines the degree of distress triggered by social isolation. “You’re not inheriting loneliness; you’re inheriting how painful it feels to be alone,” Cacioppo says.
Cacioppo believes loneliness can be overcome. He and colleagues recently conducted a meta-analysis of 20 studies on interventions for loneliness. Simply providing social support doesn’t seem to work, especially if people know they’re being looked after. “If you know people are stopping by to check on you, it makes you feel like more of a loser,” Cacioppo says. The most effective interventions were those that borrowed methods from cognitive behavioral therapy to shift people’s attention and interpretation of social situations in a more positive direction, the team reported online 17 August 2010 in Personality and Social Psychology Review. As for preventing loneliness, Cacioppo says it helps to know where your own thermostat is set and strive to stay in your comfort zone. In Loneliness, he writes: “The degree of social connection that can improve our health and our happiness … is both as simple and as difficult as being open and available to others.”