You meet family and friends regularly but still feel lonely? Scientists find a surprising reason after tracking 3,082 people for 10 years

Having a lot of people around you always doesn’t mean that you feel connected to them. Even when someone might be in regular contact with friends, go to family gatherings and speak with relatives, that person might still feel lonely. That feeling of emotional disconnection even when surrounded by others can have implications beyond mental health, specially as people get older.

The study was done on 3,082 older adults who were followed for up to 10 years. Those people who reported more loneliness had declined faster in memory and other thinking skills.

The findings were published in The Journals of Gerontology: Series B in August 2025 and it shows how feeling lonely may be different from simply having fewer social interactions.

What researchers discovered after tracking 3,082 people

The research, led by Qing Lin and senior author Cassandra Morrison, an assistant professor of psychology at Carleton University in Ottawa, analysed participants from four studies conducted by the Rush Alzheimer's Disease Center in Chicago.

All participants were at least 55 years old when they entered the study. Researchers assessed their cognitive abilities every year using 18 tests covering different aspects of brain function, including episodic memory, semantic memory, working memory, processing speed and visuospatial ability.

Loneliness was measured at each visit using a modified version of the de Jong-Gierveld emotional loneliness scale. The questions captured experiences of emptiness, abandonment or missing close relationships.

The researchers found that people with higher loneliness scores experienced faster declines across the cognitive areas examined. The association also remained when the team repeated its analysis among 2,264 participants who were considered cognitively healthy at the beginning of the study.

Why meeting family and friends may not be enough

One of the most interesting aspects of the research was that the number of social interactions did not explain the findings.

The researchers considered how many children, close relatives and friends participants had and how many of them they met at least once a month. Even after accounting for these interactions, the association between loneliness and faster cognitive decline remained largely unchanged.

This highlights a key difference between loneliness and social isolation. Social isolation is when you don’t have much contact with other people. Loneliness is the feeling that your existing relationships don’t give you the emotional closeness you want.

This means that you can have a social life and still feel lonely. Likewise, a person with a relatively small social circle doesn’t necessarily feel lonely.

Can loneliness speed up memory loss?

Although the findings point towards a link, researchers have cautioned that the study does not establish that loneliness directly causes cognitive decline.

Morrison told ScienceBlog that the research could not confidently establish which condition came first because the researchers averaged participants' loneliness scores across their visits.

"It is possible that loneliness contributes to cognitive decline, but it is also possible that early cognitive changes affect social interactions, relationships, and feelings of loneliness," she explained.