I always figured marijuana smoke, which is pretty harsh, was pretty bad. Can this be right?

1. scie nce aint so bad.co m
http://scienceaintso bad.co m/2013/12/09/a-surprise-marijuana-do esnt-cause-cancer/
A Surprise: Marijuana Doesn’t Cause Cancer!
MISTER Science Ain't So Bad
Have you ever smoked a
joint?
Because those things aren’t
exactly f ull of wonderf ul
stuf f . T here are a lot more
cancer causing things in
marijuana smoke than in
cigarette smoke. And
marijuana smoke causes precancerous changes in
bronchial tissue and leaves
f our times as much tar in the
lungs as cigarettes.
Even worse. Pot smokers
hold the smoke in their lungs
f our times longer.
MARIJ UANA NO T A CARCINO G EN
So just how bad is marijuana
f or you?
SURPRISE!
T hat’s the thing. A study by Donald Tashkin, M.D., of the University of Calif ornia in Los Angeles was a big
surprise. For pot smokers – even heavy pot smokers – there was no detectable cancer ef f ect in the head,
neck and lungs. None at all. None.
T he study was an epidemiological study that looked at hundreds of cigarette and marijuana smokers. Dr.
Tashkin speculates that maybe marijuana smoke is so potent that the cells that are af f ected are too damaged
to even become cancerous cells. I hope you f ind that comf orting. Other studies seem to show there’s
something in marijuana that inhibits cancer. One shows it cutting the growth of lung tumors in half .
What does MIST ER ScienceAintSoBad think?
T he result seems crazy. Maybe another study will ref ute this one. Or not. T here were some studies that
pointed to long term brain damage but they got upended too. Newer studies say no. Seriously. T here isn’t much
proof that this potentially bad thing is a bad thing.
If you’re a grown up, you can make your own call but don’t f orget it’s not exactly legal most places, okay?
If you’re a kid, don’t be s-t-u-p-i-d. You don’t need this.
MIST ER ScienceAintSoBad is surprised about all this. Maybe I missed something? Let me know, okay?
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2. T he drawing is mine
And don’t f orget the old saying “Better saf e than high.”