It’s a lonely time to be living in America. Several studies have found that over the past two decades, Americans have become much more socially isolated from one another: More Americans live alone or with just one other person; on average, they have one-third fewer close friends; and 25 percent of Americans now say they have no close friends at all—more than double the figure from two decades ago. While some people may enjoy a sense of solitude, many others find their isolation brings feelings of sadness or loss.
According to University of Chicago psychologists Louise Hawkley and John Cacioppo, these negative experiences of loneliness are linked to long-term health problems. Hawkley and Cacioppo asked college students and older adults (between the ages of 50 and 68) to fill out questionnaires and keep diaries about their social lives. They also looked at indicators of the study participants’ health—including their body mass index, blood pressure, and levels of stress-related hormones—and regularly checked up on the older adults’ health over a five-year period.
Their results, published in the August issue of Current Directions in Psychological Science, suggest that lonely people have significantly more trouble bouncing back from life’s stresses and strains. For instance, lonely and non-lonely college students in their study reported similar daily activities, but lonely college students experienced more stress in those activities. Among older adults, lonely individuals said they felt more helpless and threatened than did non-lonely people. What’s more, higher stress levels were associated with worse health: Lonely college students had higher blood pressure than non-lonely ones, putting them at greater risk for heart disease, and this health disparity was even greater between lonely and non-lonely older adults. Plus, Hawkley and Cacioppo found that these lonely older adults had higher levels of stress-related hormones, such as cortisol and epinephrine, which may weaken the immune system over time.
While these findings may seem depressing, Hawkley says she hopes their research underscores the costs of loneliness and helps identify ways to counteract some of those costs. “Whether isolated or not, people who perceive their social world as isolating and negative would probably benefit from interventions,” she says. She cites research suggesting the benefits of programs that promote social connectedness, especially among the elderly and chronically ill, though she notes that these programs should include certain provisions, such as transportation, for those who lack the ability to visit friends.