tobacco vs. marijuana smoke

Back in the day when I, uh, hung out with a lot of stoners, people would argue about whether the smoke from weed was better or worse for you than tobacco smoke. Some seemed to think marijuana was a divine gift that could do no wrong. Others said it was not as bad as tobacco—at least when smoked through a bong that would somehow filter the smoke (although if it was completely filtered, it would just be air, not smoke). And some thought, puff for puff, marijuana was worse than tobacco, if only because aficianados inhale deeply and hold it in, whereas smoking tobacco is normally a quick hello-and-goodbye.

Now scientists have stepped in to clear away some of the haze, with a study in Harm Reduction Journal that concludes:

Available scientific data, that examines the carcinogenic properties of inhaling smoke and its biological consequences, suggests reasons why tobacco smoke, but not cannabis smoke, may result in lung cancer.

Link to study

Stoners and medical marijuana users may rejoice, but remember there are all sorts of other ill effects of smoke besides just cancer. I knew a guy who, after taking a huge toke, started hacking uncontrollably and pulled a major muscle in his back.