Why do you effectively ignore those problems and focus solely on IQ and schizophrenia?
I don’t think that studies have ever proven a connection with decreased IQ
That was indicated only in those who used during adolescence; has nay such study even been done for alcohol?
and schizophrenia from alcohol.
You are asking for defacto approval of drugs by the FDA that have shown that at least 2% of those who use the drugs develop schizophrenia with heavy use.
No, what's been shown is a correlation between marijuana and schizophrenia - which can equally well be explained by schizophrenia leading to an attempt to self-medicate with marijuana, or by a common factor that leads to both marijuana use and schizophrenia.
"But here's the conundrum: while marijuana went from being a secret shared by a small community of hepcats and beatniks in the 1940s and '50s to a rite of passage for some 70% of youth by the turn of the century, rates of schizophrenia in the U.S. have remained flat, or possibly declined. For as long as it has been tracked, schizophrenia has been found to affect about 1% of the population." (http://www.time.com/time/health/article/0,8599,2005559,00.html)
You are wrong, there have been definitive studies that show both, a decreased IQ of up to 8 points in marijuana users under 21 and at least 2% of the heavy marijuana users developing schizophrenia. Neither the IQ loss or the schizophrenia is curable. They are lives wasted.
It’s true that studies show a decreased use of marijuana among adults, but the sad part is that the same studies indicate a big increase in marijuana use among teenagers. Legalizing the drugs will not keep them out of the hands of teenagers.