FYI. It's an editorial and the author is a resident physician so feel free to apply some skepticism but the studies he cites ought to be relevant information for some of the debates we've had in here ...



http://online.wsj.com/article/SB1000...mod=hp_opinion

Though they receive little attention in the legalization debate, the scientific studies showing an association between marijuana use and schizophrenia and other disorders are alarming. A 2004 article in the highly respected British Journal of Psychiatry reviewed four large studies, all of which showed a significant and consistent association between consumption of marijuana (mostly during teenage years or early 20s) and the later development of schizophrenia. The review concluded that marijuana is a "causal component," among others, in the development of schizophrenia and other psychotic disorders.
A 2007 study in the Lancet, a British medical journal, concludes that using marijuana increases the risk of young people developing a psychotic illness, such as schizophrenia. This risk is greatest—up to a 200% increase—among those who use marijuana heavily and who start using at a younger age.