Australian researchers looked at more than 8,000 people with psychotic illnesses who used marijuana and more than 14,000 people with psychotic illnesses who did not.
They found those who used marijuana were nearly three years younger when they developed schizophrenia or other mental illnesses, compared with their drug-free peers.
Researchers say there is a chance that pot smokers may have a predisposition to psychiatric disorders. They say smoking pot can lead to an early outbreak or conversion to psychosis that would not have happened otherwise.
