The harmful effects of loneliness are well documented in seniors, who suffer from isolation and an increased risk of disease, dementia, and suicide when they feel alone. A worryingly similar trend, however, also applies to a much younger, increasingly isolated crowd: millennials. On Tuesday, a study in Psychological Medicine reported that lonely millennials are more likely to have mental health problems, use negative strategies to cope with stress, and engage in risky health behavior.

“Young adults’ experience of loneliness co-occurs with a diverse range of problems, with potential implications for health in later life,” the researchers explain in the paper, first-authored by Timothy Matthews, Ph.D. of the University of London Institute of Psychiatry, Psychology and Neuroscience. “The findings underscore the importance of early intervention to prevent lonely young adults from being trapped in loneliness as they age.”

In this survey, the team examined data collected in the Environmental Risk Longitudinal Twin Study, which includes information about 2,232 people born between 1994 and 1995 — squarely millennial individuals — in England or Wales. At age 18, each of these participants reported how lonely they were and how they felt about their mental and physical health, their relationship with technology, and their overall satisfaction with life. Seven percent of these respondents, regardless of gender or socioeconomic status, said they often felt lonely, while 23 to 31 percent reported that at least some of the time they felt isolated or lacking in companionship. These feelings were linked to problems that bubbled up later in life.

Sad millennial man
Researchers link loneliness to poor mental health.

The team’s analysis showed that, for every two-point increase in loneliness, the risk of developing depression, anxiety, or suicidal thoughts doubled. An increase in reported loneliness was also correlated with the odds of being unemployed rising by 38 percent.

“They were less confident in their employment prospects and were more likely to be out of work,” the scientists write. “Lonelier young adults were, as children, more likely to have mental health difficulties and to have experienced bullying and social isolation. Loneliness was evenly distributed across genders and socioeconomic backgrounds.”

Matthews told The Guardian on Tuesday that people who express that they often feel lonely could be giving “a warning sign they are struggling in other areas of life.”

Previous research has linked millennial feelings of isolation to ill health. In 2017, scientists pinpointed a link between feelings of loneliness with worse overall sleep quality. Loneliness, the researchers explained, is a form of biological stress, and it causes the body to release more of the stress hormone cortisol, which is known to interfere with sleep.

Nobody is really sure why loneliness can lead to poor mental and physical health, but some researchers think the relationship has evolutionary roots. Homo sapiens, they argue, evolved to desire social inclusion and cohesion for survival’s sake — and in today’s isolated world, that craving is rarely fulfilled.