ersely, people who engage in meaningful, productive activities with others tend to live longer, boost their mood, and have a sense of purpose. These activities seem to help maintain their well-being and may improve their cognitive function, studies show.
Breaking ground in loneliness research
Much of what we know about the causes and effects of social isolation and loneliness comes from the groundbreaking research of the late John T. Cacioppo, Ph.D., former director of the Center for Cognitive and Social Neuroscience at the University of Chicago and an NIA grantee.
Dr. Cacioppo’s research found that being alone and loneliness are different but related. Social isolation is the objective physical separation from other people (living alone), while loneliness is the subjective distressed feeling of being alone or separated. It’s possible to feel lonely while among other people, and you can be alone yet not feel lonely.
A pioneer in the field of social neuroscience, Dr. Cacioppo passed away in March 2018. His wife and collaborator, Stephanie Cacioppo, Ph.D., continues this work as assistant professor of psychiatry and behavioral neuroscience at the University of Chicago and director of the university’s NIA-supported Brain Dynamics Laboratory.
“The misery and suffering caused by chronic loneliness are very real and warrant attention,” she said. “As a social species, we are accountable to help our lonely children, parents, neighbors, and even strangers in the same way we would treat ourselves. Treating loneliness is our collective responsibility.”
Although there is more to learn, the understanding of the mechanisms of action of loneliness and its treatment has increased dramatically since scientific investigation began more than two decades ago, according to Dr. Stephanie Cacioppo. Among the novel predictions from the Cacioppo Evolutionary Theory of Loneliness is that loneliness automatically triggers a set of related behavioral and biological processes that contribute to the association between loneliness and premature death in people of all ages. Research is headed toward the systematic study of these processes across generations, Dr. Cacioppo explained.
Understanding the biology of loneliness
Losing a sense of connection and community changes a person’s perception of the world. Someone experiencing chronic loneliness feels threatened and mistrustful of others, which activates a biological defense mechanism, according to Steve Cole, Ph.D., director of the Social Genomics Core Laboratory at the University of California, Los Angeles. His NIA-funded research focuses on understanding the physiological pathways of loneliness (the different ways that loneliness affects how your mind and body function) and developing social and psychological interventions to combat it.
For example, loneliness may alter the tendency of cells in the immune system to promote inflammation, which is necessary to help our bodies heal from injury, Dr. Cole said. But inflammation that lasts too long increases the risk of chronic diseases.
Loneliness acts as a fertilizer for other diseases,” Dr. Cole said. “The biology of loneliness can accelerate the buildup of plaque in arteries, help cancer cells grow and spread, and promote inflammation in the brain leading to Alzheimer’s disease. Loneliness promotes several different types of wear and tear on the body.
People who feel lonely may also have weakened immune cells that have trouble fighting off viruses, which makes them more vulnerable to some infectious diseases, he added.
NIA-supported research by Dr. Cole and others shows that having a sense of mission and purpose in life is linked to healthier immune cells. Helping others through caregiving or volunteering also helps people feel less lonely.
“Working for a social cause or purpose with others who share your values and are trusted partners puts you in contact with others and helps develop a greater sense of community,” he noted.
Researching genetic and social determinants of loneliness
In another NIA-funded study, researchers are trying to understand the 