6 Ways Loneliness Can Harm Your Health — and How to Cut Your Risks

A 2022 statement from the American Heart Association (AHA) agreed that social isolation and loneliness can increase the risks of having or dying from heart attacks and strokes. Lonely or isolated people who already have heart disease are more likely to die from it; and those who’ve had one stroke may be at higher risk for another, says Crystal Wiley Cené, M.D., a professor of clinical medicine and chief administrative officer for health equity, diversity and inclusion at University of California San Diego Health. She chaired the writing group for the AHA’s statement.

3. Diabetes

People with weak social ties are more likely to get diabetes and are less able to manage it well, studies have found. They also are more likely to suffer complications from the disease, such as heart attacks, vision loss, foot problems and kidney damage, regardless of their blood sugar levels.

4. Infections

In one study, people exposed to a cold virus were much less likely to get sick if they had at least six social roles (parent, spouse, friend, family member, coworker or club member), compared with if they had three or fewer roles. A study of COVID-19 vaccination showed weaker immune responses in people who felt disconnected from their neighbors.

5. Cognitive decline and dementia

Adults over age 50 who were followed for an average of six years were about 50 percent more likely to develop dementia if they experienced prolonged loneliness and social isolation, a research review found. Another study that looked at midlife adults found those who were persistently lonely were more likely to later develop Alzheimer’s disease, the most common type of dementia. Additional research has found faster cognitive decline in adults over 65 who report loneliness.

6. Depression and anxiety

It may not be surprising that loneliness and isolation can lead to poor mental health. And the connection goes both ways: Depression and anxiety can cause people to withdraw and feel lonelier. But research also shows that having someone to confide in can sometimes stave off depression, even in people at high risk. Social connection also may lower the risk of suicide, especially for men. 

The link between loneliness and your health

The links between social disconnection and poor health are rooted in our most basic biology, as well as our psychological and behavioral responses, experts say.

“Penguins who huddle together stay warmer,” and humans aren’t much different, says researcher Kerstin Gerst Emerson, a clinical associate professor at the University of Georgia. “We’ve always survived better if we are together.”

Brigham Young University’s Holt-Lunstad says multiple biological mechanisms are at work. One that may be particularly important, she notes, is chronic inflammation, which is linked to many different diseases and is often elevated in socially isolated people.

Spikes in stress hormones, immune system disturbances and changes in gut microbes also may play roles, the Surgeon General’s advisory says. All that dysregulation can cause a lot of “wear and tear on the body over time,” Holt-Lunstad says.

But loneliness and isolation also change how people behave. For example, having someone around to encourage you to take your medications and go to the doctor when needed may help you manage your health problems, says Cené of UC San Diego Health.

Other people also may help you eat better and move more, Emerson says. “If you’re lonely and alone — and this happened to a lot of us during the pandemic — maybe you just eat a bowl of cereal for dinner because you can’t be bothered to make a whole meal for yourself.”

The person who walks half a block on their own might take a much longer walk with a friend. And having a friend or neighbor who checks in on you regularly can literally save your life, she says.

Join AARP on July 11 at 6:30 p.m. ET for a Happiness Empower Hour. The free online event will focus on simple yet effective steps you can take to connect with people and improve your overall well-being. For more information and to register for the live event, visit AARP’s Virtual Community Center.