A broad new analysis published in the journal Nature Human Behavior demonstrates that social isolation and loneliness can lead to premature death.
The systematic review combined data from 90 studies with more than 2 million participants to investigate the connection between social isolation, loneliness, and early death among the general population, people with heart disease, and people with cancer; the studies followed participants for anywhere from six months to 25 years.
The review defined social isolation as a measurable lack of contact with other people; many participants who lived alone experienced social isolation. It defined loneliness as a subjective feeling related to lacking quality in social relationships.
The analysis found people who experienced social isolation had a 32% higher risk of dying early compared to those who were not socially isolated. Participants who experienced loneliness were 14% more likely to die early compared to those who did not. Researchers explain that’s most likely because social isolation means a lack of contact with people, whereas participants who are lonely have contact with others, but feel less strong connections.
The study also found that among people with cardiovascular disease and cancer, participants who were socially isolated were more likely to die earlier from those conditions compared to participants who were not.
What’s going on here? Researchers believe that social isolation is a form of stress and that social connection is essential for humans, who evolved to rely on each other for survival. Even though we no longer need social groups to help with food collection and protection like humans thousands of years ago, modern people remain wired to connect with others.
Yet, a recent report by the U.S. surgeon general documents a decline in social connections across all age groups. The report found more than one-third of adults aged 45 and older feel lonely, and nearly one-fourth of adults aged 65 and older are socially isolated. And it found that young people ages 15 to 24 have 70% less social interaction with their friends compared to young people two decades ago.
The report also demonstrated that loneliness is equally bad for our health as smoking, having serious effects on both mental and physical health. Data show loneliness and isolation are linked to sleep problems, inflammation, pain, insomnia, depression, anxiety, heart disease, stroke, diabetes, addiction, suicidality and self-harm, and dementia.
It’s important to note that there was heterogeneity—or variation—and publication bias among the studies in the analysis, explained Anthony Ong, Cornell psychology professor and director of the Center for Integrative Developmental Science and Human Health Labs. He contributed to the surgeon general’s report on loneliness.
“This suggests the need to develop and validate standardized and comprehensive measures of social isolation and loneliness that capture the complexity and multidimensionality of these concepts,” he said.
Most studies of social isolation and loneliness focus on understanding these issues in isolation, which misses the complex interplay between them, he said.
“For instance, individuals may experience low social isolation due to the size or structure of their social network but still report high levels of loneliness due to unfulfilled social needs or unsatisfying relationships,” Ong explained. “Similarly, individuals may exhibit high social isolation but low loneliness due to personal preferences for solitude or a sense of fulfillment from other sources outside of social connection.”
Future research should consider the interactions between social isolation and loneliness, so that we can develop a more complete understanding of how to address the problem, he said.
Nevertheless, the surgeon general’s report offers community- and policy-based solutions to this nationwide problem. They include strengthening social infrastructure by supporting volunteer organizations, religious groups, public transit, community schools, libraries, and green spaces, along with enacting public policies that support connection.
The report calls for health care providers to assess patients for social isolation and loneliness, and help them make connections in their communities. It calls for improving digital platforms to encourage social connection and discourage marginalization and discrimination, especially for younger people. And it encourages everyone to cultivate values of kindness, respect, and commitment to others within their communities.
The take-home message: Loneliness and social isolation are persistent and dangerous problems in American society. This is one public health issue that we can all help to address; reach out to your neighbors, strike up a conversation with someone you encounter in public, or lend a hand to someone in need.
