The Digester
Week 7, Friday

Hot nights linked to surge in youth suicide crisis calls and heat-related mental illness

A 2026 systematic review and hotline data find hotter nights increase suicide-related crisis calls and raise emergency mental health visits among people 24 and under, with clear policy implications.

  • In the two days after hot nights there were an additional 19 suicide calls per 100 crisis calls.
  • Exposure to high temperature was associated with a 13% higher risk of hospital visits or hospitalizations for mental health disorders among people aged 24 and under.
  • High temperature exposure was linked to a 14% higher risk for schizophrenia visits and an 18% higher risk for depression visits.
  • Each 1°C increment in daily mean temperature corresponded to about a 1% higher suicide risk in pooled studies.
  • Likely drivers include disrupted sleep from hot nights, increased substance use and impulsivity, and acute stress from temperature extremes.
  • Researchers recommend early-life mental health interventions and climate adaptation policies and note limited evidence from lower-income countries.