It's a shame that studies on marijuana and its effects on users were blocked and considered taboo subjects for so long. The reason we have these types of conflicting messaging about the safety/danger of marijuana use, is because there has not been enough research or longitudinal studies in those regards.

Can you become addicted to marijuana? Maybe. Does marijuana cause cancer? Maybe. Does it cause this or that or the other thing? Maybe.

For now we have to make assumptions. If you're worried about getting addicted, you should probably stay away. If you're worried about it being a carcinogen, you should probablt stay away. We're probably a long ways away from having conclusive evidence to show either way.