A new study analyzing data from 18 countries suggests that loneliness—distinct from social isolation—may accelerate cognitive decline and physical deterioration in older adults. The research, published in the journal Nature Human Behaviour on June 15, 2026, examined data from over 130,000 participants aged 50 and older.
Lead author Dr. Emily Chen of the University of California, San Francisco, stated: 'We found that perceived loneliness, rather than objective social isolation, was consistently associated with faster declines in cognitive function and physical health over a 10-year follow-up period.' The study controlled for factors such as age, sex, education, and baseline health.
Key findings indicate that lonely individuals had a 15% higher risk of developing cognitive impairment and a 20% increased risk of mortality compared to those who did not report loneliness. The effects were consistent across all 18 countries, including the United States, United Kingdom, Japan, and Brazil.
Dr. Chen added: 'These results highlight the importance of addressing loneliness as a public health issue, especially among aging populations. Interventions that foster meaningful social connections could help mitigate these risks.' The study was funded by the National Institute on Aging.
