Smoking Pot Lowers IQ

[Kenjinagano]

people need to read this article a bit better (either that or they are decieved by the topic title and did not read the article at all which is also a huge possibility)

people who picked up the habit as adults had no IQ drop, suggesting that marijuana may not be as harmful to the mature brain.

The study proved that smoking pot as a teenager

saw their IQ drop an average of 8 points, the equivalent of going from an A to a B student.

they do not know why the adult brain didn't suffer from an IQ drop but If I had to guess (personal opinion here) then its probably similar to the effects alcohol has on a teenagers brain.

Edit: that said IQ is not an exact measure of your intelligence but more of a way to see how fast you can take up knowledge.