Loneliness (as health risk)

Loneliness is the subjective feeling of being socially disconnected. It is now a recognized risk factor for heart disease, dementia, and early death. Meta-analyses by Holt-Lunstad and colleagues make the case. One (2010, PLOS Medicine) found that strong social ties came with about 50% greater odds of survival. Another (2015) studied social isolation, loneliness, and living alone. Each one independently raised death risk by roughly 26 to 32%. Holt-Lunstad compared that to smoking up to 15 cigarettes a day. That framing reached the 2023 US Surgeon General's advisory on the loneliness epidemic. How does it harm you? Loneliness throws off your inflammation, your sleep, and your stress hormones (the HPA axis). So in longevity science, easing loneliness through community, purpose, and relationships is a primary, evidence-based fix.

Last reviewed: June 22, 2026

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