Social isolation
“Why is loneliness now as dangerous to health as smoking?”
Root causes (expand to see solutions)
Loneliness is a physical health risk that affects the heart, immune system, and brain, raising the odds of early death. It is now spreading through society:
What's at stake
Loneliness raises the odds of early death as much as smoking 15 cigarettes a day, and more than doubles the odds of a suicide attempt; it also accelerates cognitive decline and heart disease, and deepens depression.
In its most extreme form, isolation ends in dying alone, undiscovered for days, already a tracked national statistic from Japan to South Korea; and because it is self-reinforcing, it spreads through families and neighbourhoods.
The global picture
Japan
High severity
Japan recorded 76,941 unattended deaths in 2025, of which 22,222 bodies went undiscovered for eight days or more; nearly 80% of victims were 65 or older.Nippon.com / National Police Agency, 2026
This problem occurs worldwide, not concentrated in any one region.