Loneliness and Memory Loss Are Linked — But a New Study Reveals a Twist

Many older adults find that life becomes quieter with age. The children have grown up, friends move away, retirement changes, daily routines or health problems make it harder to get out and about. So if you’ve ever been told to go out more, stay socially active or spend time with friends “to keep your mind sharp,” there’s good reason for that advice.

A large European study found that older adults who felt lonelier tended to have worse memory than those who were less lonely. However, loneliness did not appear to make their memory decline any faster over time. Instead, it seemed to affect where people’s memory started rather than how quickly it declined.

Read: Loneliness vs. being alone: The difference matters

Discover: New Study: The Rise of Loneliness Among Older Adults

Loneliness May Affect Memory Earlier Than Expected

Feeling lonely is more common than many people realize. Nearly half of older adults in the United States report feeling lonely—and that doesn’t necessarily mean they’re alone. And loneliness is more than an unpleasant emotion—it has been linked to a wide range of health problems. For example, a recent study of more than half a million older adults found that feeling lonely was associated with a 31% higher risk of dementia.

To see whether loneliness influences memory over the years, the study, published in the journal Aging & Mental Health, followed more than 10,000 adults aged 65 to 94 from 12 European countries for about six years.  To measure loneliness, researchers asked participants how often they felt they lacked companionship, felt left out, and felt isolated from others. Participants answered “often,” “some of the time” or “hardly ever/never.” Based on their responses, they were grouped into low, average or high levels of loneliness.

Researchers also tested memory using a simple word recall exercise. Participants listened to a list of 10 words and tried to remember as many as they could immediately, then again five minutes later. They also accounted for other factors that could influence memory, including depression, diabetes, high blood pressure and physical activity.

Older adults who reported high levels of loneliness scored lower on both memory tests right from the start of the study.  But over the next six years, their memory declined at about the same pace as everyone else’s.

Dr. Luis Carlos Venegas-Sanabria, a geriatrician and researcher at the Universidad del Rosario and the study’s lead author, said the finding surprised the team. “It suggests that loneliness may play a more prominent role in the initial state of memory than in its progressive decline,” he said in a news release.

“Not too surprisingly, in light of that finding, loneliness has been associated with decreased immunity… [and] with faster progression of Alzheimer’s Disease.”

Dr. John Cacioppo, author of “Loneliness: Human Nature and the Need for Social Connection”

Age Mattered Most

The biggest factor influencing memory decline wasn’t loneliness—it was age.

Adults aged 75 to 84 experienced a slightly faster decline in immediate memory than younger older adults, while those aged 85 and older declined about twice as fast.  Diabetes was also linked to a slightly steeper decline in delayed memory over time. Meanwhile, depression, high blood pressure and diabetes were all associated with poorer memory at the start of the study

 On the brighter side, participants who reported good overall health, stayed physically active and regularly took part in social activities tended to have better memory scores. Women also performed better on the memory tests than men.

Surrounded by People Yet Lonely

The findings also highlight an important distinction that often gets overlooked: loneliness isn’t the same as social isolation.

The researchers defined loneliness as the distressing feeling that your relationships don’t meet your social or emotional needs. Social isolation, on the other hand, refers to objectively having few social contacts or interactions. That means you can have plenty of family members and friends around you yet still feel lonely—or live alone without feeling lonely at all.

The finding that loneliness is associated with lower memory fits with a growing body of research. A 2025 review of studies involving more than 20,000 adults aged 50 and older found that people who rarely or never felt lonely generally performed better on cognitive tests than those who felt lonely most often.

That’s why experts stress that loneliness isn’t simply about how many people are around you. 

“Someone can be lonely but not isolated, or isolated but not lonely.” Dr. Julianne Holt-Lunstad told the American Psychological Association.

Why Loneliness Still Matters

The findings don’t mean loneliness is harmless. While it didn’t appear to speed up memory decline, a growing body of research suggests loneliness is still linked to poorer brain health.

Studies found abnormal structure and activity in key brain regions responsible for decision-making and executive function, memory, social awareness, and threat detection, in lonely people. A brain imaging study also found that older adults who reported feeling lonely were more likely to have higher levels of amyloid—a sticky protein linked to Alzheimer’s disease—in their brains, even though they had no signs of memory problems.

One possible reason is the body’s response to chronic stress. Dr. John Cacioppo, author of Loneliness: Human Nature and the Need for Social Connection, explained that lonely people tend to have a larger spike in cortisol—the body’s main stress hormone—when they wake up. Over time, that may make the body less able to control inflammation.

“Not too surprisingly, in light of that finding, loneliness has been associated with decreased immunity… [and] with faster progression of Alzheimer’s Disease,” Cacioppo said in a Big Think interview.

Take Loneliness Seriously

Being lonely may not make your memory fade faster. But if it affects where your memory starts, it’s worth taking seriously.

So if life has become a little quieter over the years, don’t dismiss feelings of loneliness as simply part of getting older.  Reach out to family, friends, or your community. Nurturing relationships that help you feel truly connected may benefit not only your emotional well-being, but your brain health, too.