For how we live.
The famous cigarette comparison is a communications gloss on a robust but observational finding: people with stronger social ties are markedly more likely to survive follow-up.
A registered report fit identical models to 11 longitudinal studies covering 175,070 people. The subjective feeling carried the signal; the objective count of social contacts largely did not.
A 1,151-person Hong Kong trial used trained lay counsellors, not clinicians, and no internet. The effect sizes are small, and the authors are explicit that they do not know whether it travels.
Loneliness tracked with depression, perceived stress, psychotic-like experiences and suicidal ideation. A prevalence that high raises a question about what the measure is capturing.
Across 2.48 million survey responses in 159 countries, the share of people with no one to turn to rose 13.4% between 2009 and 2024 — all of it after 2019.