Last time you visited your doctor, did he or she ask if you felt lonely? Did your doctor inquire about how many friendships you have or ask about how many community groups you are involved with?
There’s a growing body of research showing that extended loneliness and isolation are detrimental to health, and can even shorten people’s lives. One example is an analysis of about 70 studies conducted between 1980 and 2014 looking into loneliness and social isolation as risk factors for mortality. It found a 26% increased likelihood of death for reported loneliness, a 29% increase for social isolation and a 32% increase for living alone.
In the report of that research, the author, Julianne Holt-Lunstad, a psychologist and professor at Brigham Young University, warned that loneliness could reach epidemic proportions by 2030.
The prevalence of loneliness and isolation may already be fairly widespread; a 2018 AARP study found that one-third of people over age 45 experienced loneliness.
According to the National Institute for Health Care Management (NIHCM), loneliness raises the risk of premature death as much as smoking or obesity. An estimated $6.7 billion in annual federal spending is attributable to social isolation among older adults, NIHCM says.
This phenomenon is not limited to the United States. Many studies include other countries, and the World Health Organization recognizes the importance of social connections. Researchers worry that we are facing a loneliness epidemic, which can have serious health effects.
Defining and Measuring Loneliness and Isolation
While research reveals that strong social connections are protective to your health, experts caution that we should not conflate the feeling of loneliness with social isolation.
“We focus so much on traditional risk factors. ‘Do you smoke? Are you overweight?’ But we do not ask about loneliness and isolation, which have huge health effects.”
As Louise Hawkley, a psychologist and senior research scientist at the University of Chicago, explains, social isolation is an objective, quantitative measure. You can determine how many friends people have and how often they interact with them as well as whether people participate in civic engagements, volunteer, have religious affiliations and other aspects of their social life.
On the other hand, loneliness is more subjective. Someone may be surrounded by people but feel quite lonely due to not feeling like they’re part of the group or that they have any close relationships. And when it comes to loneliness, the quality of the relationship matters.
“Because of the importance of the quality of the relationship, you can’t just put a bunch of lonely people in a room and expect them to make friends,” Hawkley says.
How Loneliness and Isolation Affect Health
Research has shown that loneliness can lead to depression, which, untreated, can eventually lead to serious physical health issues, Hawkley says.
When a person experiences loneliness, the level of the stress hormone “cortisol” increases, which can compromise the immune system and lead to inflammation in the body. This can increase the risk of many health issues, including heart disease, high blood pressure, diabetes and dementia, according to the Cleveland Clinic.
Some researchers have suggested that anti-inflammatory medications could help. However, Dr. Carla Perissinotto, a geriatrician who researches loneliness at the University of California San Francisco (UCSF), points out complications.
“There is very good research [showing that] some anti-inflammatory medications actually worsen cardiovascular disease and worsen kidney disease,” she says. “The thing is, you’re not reducing loneliness, you’re reducing the physiological effects of loneliness. So, it’s really more of secondary prevention or tertiary prevention, not primary prevention.”
Here is a sample what research has found regarding some of these conditions and loneliness and isolation:
Cardiovascular disease: So far, the research about the effects of loneliness and isolation on the cardiovascular system has been among the most robust. According to a study published in 2015 by Nicole Valtorta, doctoral fellow at the University of York in the U.K., feeling lonely or being socially isolated is associated with defective immune functioning and higher blood pressure.
In her data review, Valtorta found that poor social relationships were associated with a 29% increase in coronary heart disease and a 32% increase in risk of stroke. Further, cardiovascular disease prognosis is worse among people with poorer social relationships.
Stroke: Loneliness has been associated with increased prevalence of stroke and increased mortality, disability and poor recovery following stroke, according to research published in 2015 and conducted by Trisha Petitte, an assistant professor at the West Virginia University School of Nursing.
Stroke is linked to an increased risk of post-stroke depression, Petitte wrote. Factors that influence and predict the degree of loneliness and depression among stroke survivors include the presence of loneliness and depression prior to the stroke, stroke severity and whether the patient went to a nursing or rehabilitation facility.
Dementia and Alzheimer’s disease: In a 2007 study led by Robert Wilson, a professor in the department of Neurological Sciences at Rush Medical College, a cohort of about 820 older adults without dementia were checked on annually for up to four years. The study found that lonely individuals were more than twice as likely to develop dementia than those who were not lonely.
How Loneliness Can Impact Sleep and Health
One of the most fascinating connections between loneliness and health is poor sleep quality. There is an evolutionary basis for this thinking, which was pioneered by the late researcher John Cacioppo, a psychologist at the University of Chicago and founder of the field of social neuroscience.
Hawkley, who authored articles with Cacioppo, explains that lonely people can feel the hypervigilance a primitive hunter might have felt without others around to guard against predatory animals. Hawkley says this feeling is still wired into our brains and does not necessarily go away at night.
“It encroaches on your sleep, your most vulnerable time,” Hawkley says. “How can you sleep soundly if your brain is hyperalert for a threat?”
Even if lonely people are not waking to the point of consciousness, they are not getting enough restful sleep. And this, in turn, can significantly contribute to poor health, Hawkley adds.
Asking the Right Questions
Many researchers and organizations are alarmed enough about the health effects of loneliness and isolation to call for more attention and study in this field. Many questions remain unanswered — especially in terms of how to address this issue.
Perissinotto, at UCSF, spends a lot of time thinking about loneliness because she sees it in her practice.
“We focus so much on traditional risk factors. ‘Do you smoke? Are you overweight?’ But we do not ask about loneliness and isolation, which have huge health effects. So, part of it is asking the right questions,” she says.
Perissinotto also is interested in anthropology — she has a bachelor’s in it — and wonders about the causes of loneliness and isolation in the U.S.
“As an anthropologist and a geriatrician, I’m very interested in understanding, why are we seeing so much loneliness and isolation?” she asks.
“And why is it that our older adults don’t feel valued?” she continues. “Why is it that solutions we are proposing are not really aimed at human connection and what binds us to each other, and how we form societies? That is more interesting to me and that is where I think we need a lot of work — but that’s a lot harder.”