WEED doesn't cause cancer, it's the way we ingest it into our system, by inhaling SMOKE!! Smoke is bad, bad, bad shit...
Um....what else...apparently if your border line skitso it can push you over the edge. Can cause depression, yet depressed people claim it gives them a lift. (like me) BUT I can come down off my little lift like a tonne of bricks some days!!
MEMORY....how can we forget that effect!! It does shockin' stuff to your short term memory. Can repress old memories eg. childhood stuff, but it all comes back if you lay off the smoke for awhile. It's never GONE forever!
Apart from that.....can't really come up with any other cons, can tell ya lots of pro's.....