Mental health professionals were concerned about loneliness well before we all started social distancing to help contain the spread of the novel coronavirus.
"We were in the middle of a loneliness epidemic before COVID-19, and having to further distance from the world ultimately can be detrimental to our overall mental health and wellbeing," says Nina Vasan, MD, MBA, clinical assistant professor of psychiatry at Stanford University and chief medical officer of Real, an on-demand therapy platform.
Loneliness is a state of mind of being alone or separated from others. It should not be confused with social isolation, which is physical separation from other people, commonly associated with living alone.
"In that sense, it is possible to experience loneliness with others around, and it is possible to be alone but not feel lonely," Dr. Vasan says.
Here's a closer look at loneliness and the startling ways it can affect your health.
The Dangers of Loneliness
Mental health professionals are learning that loneliness can pose significant risks to your health.
1. Loneliness Is Linked With Depression
While loneliness is distinct from depression, it has been associated with depressive symptoms.
Researchers found that social disconnectedness is a unique risk factor for loneliness, which predicted higher depressive symptoms in individuals, according to a January 2020 study in the Lancet. The study also supported the reverse: People with depression were also more likely to feel isolated.
2. It's Connected to Inflammation
There seems to be a link between loneliness and inflammation, according to a December 2015 study in the Proceedings of the National Academy of Sciences. Research suggests that loneliness may weaken the body's immune response to cause more inflammation, which can in turn increase risk for chronic disease.
A July 2020 report in the Perspectives on Psychological Science found that interpersonal stressors, such as loneliness, are connected to increased risk of diseases, including respiratory viruses, evoking the possibility of greater vulnerability to SARS-CoV-2, the virus that causes COVID-19.
"Loneliness can be harmful for long-term immunity, making you more susceptible to pathogens like bacteria and viruses," Dr. Vasan says.
"It is possible to experience loneliness with others around, and it is possible to be alone but not feel lonely."
3. It's Tied to Higher Chances of Heart Disease
Loneliness may increase a person's odds of developing heart problems, too. A May 2016 study in Heart found about a 30 percent higher chance of stroke or heart disease among people who scored poorly on measures of social relationships.
The researchers attribute this link to a variety of behavioral, biological and psychological factors, such as behaviors like smoking or physical inactivity that are more common among individuals who are lonely.
4. Loneliness Is Linked to High Blood Pressure
People who experience loneliness may be more susceptible to high blood pressure, according to a first-of-its-kind March 2010 study in Psychology and Aging. Still referenced widely today, the research linked levels of loneliness with greater increases in systolic blood pressure over a four-year period among a diverse group of people.
The mechanism behind this link is not completely understood, but it points to how loneliness may be associated with earlier or more dramatic changes to the arteries, the authors note.
5. It's Associated With Cognitive Decline and Dementia
Loneliness can pose unique challenges to older adults, according to a February 2020 National Academies of Sciences, Engineering and Medicine report, due to risk factors like living alone or the loss of family and friends.
That's particularly problematic because older adults are also already at higher risk of certain loneliness-linked health conditions, such as cognitive decline and dementia.
An August 2019 study in the International Journal of Environmental Research and Public Health used data from the Chinese Longitudinal Healthy Longevity Survey to investigate the association between loneliness and cognitive decline among older men and women in China. The researchers concluded that loneliness was a significant risk factor for cognitive impairment among older men, but not women.
Earlier, loneliness was linked with a 40 percent increased risk of dementia in an October 2018 Journal of Gerontology: Psychological Sciences study analyzing data from 12,000 participants collected over 10 years, the largest sample for this topic.
"If aging adults are living in environments with limited social interaction, their dementia can worsen over time," Dr. Vasan says.