Marijuana and Schizophrenia

Just wondering if anyone here has info on its relevance to later developments of SZ. I wonder because my brother has SZ. He is 28, I am 21 and just about the most suseptible to SZ I'll ever be. Being hereditary, I have a 10% chance of getting it just by being related. Siblings are roughly 10%, and they say siblings who smoke makes it almost inevitable (which I dont believe). They say,

"People with such a vulnerability should avoid cannabis like the plague,".

Without the effects of the drug, such a person might live their whole life without ever experiencing mental health problems. It has been estimated, for example, that one in 20 people that have schizophrenia today would never have developed the illness without exposure to cannabis.

Professor Castle compared the effect to feeding sweets to a diabetic. While high sugar content foods did not cause too many problems for most people in the short term, they could be catastrophic for diabetics."


I know reseach is deeply divided on this, with both sides maybe blowing stats out of proportion to further their arguments, so are any of you in my position? help?

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