A new study released by the American Journal of Public Health draws an astounding conclusion from its analysis of suicide data for 1999 to 2007 from states which had legalized medical marijuana:
Suicides among men aged 20 through 39 years fell after medical marijuana legalization compared with those in states that did not legalize... after adjustment for economic conditions, state policies, and state-specific linear time trends... legalization was associated with a 10.8% reduction in the suicide rate of men aged 20 through 29 years and 30 through 39 years, respectively.
The study says that the actual mechanism through which suicides are reduced by medical weed legalization "remains a topic for future study," but it does acknowledge one possible interpretation:
The negative relationship between legalization and suicides among young men is consistent with the hypothesis that marijuana can be used to cope with stressful life events.
The authors of the study said that the data for females was "less precise."