A role of sunshine in the triggering of suicide

Epidemiology. 2002 Jan;13(1):106-9. doi: 10.1097/00001648-200201000-00017.


Several reports indicate that suicide follows a seasonal pattern with a dominant peak during the month of maximum daylight. The purpose of this study was to evaluate the hypothesis that sunshine exposure may trigger suicidal behavior. We found a remarkably consistent pattern of seasonality with peak incidence around June in the northern hemisphere and December in the southern hemisphere. Moreover, there was a positive association between the seasonal amplitude of suicide (measured by relative risk) and total sunshine in the corresponding country. These findings indicate that sunshine may have a triggering effect on suicide, and suggests further research in the field of sunshine-regulated hormones, particularly melatonin.

MeSH terms

  • Humans
  • Poisson Distribution
  • Risk Factors
  • Seasons*
  • Suicide / statistics & numerical data*
  • Sunlight*