>If heroin really is "so good," why does it have such a tiny share of the illegal drug market? Marijuana is more than 45 times as popular. One possible reason is that people are squeamish about needles and uncomfortable consuming drugs intravenously.
I am not a fan of marijuana (or any street drug) but it is incredibly hard to mess it up. It has a fantastic 'therapeutic index' - a big fat window between the dosages where it starts having useful effects and those where it starts potentially harming you. (anecdotally I would wonder about impact on lifestyle, but killing yourself with pot would be pretty tough, and expensive) This is a big contrast from serious down…
It seems to be impossible to actually overdose from the THC contained in marijuana. No one has actually managed to kill a large mammal with THC, but they have managed to kill small rodents.
Extrapolating up it seems that you might be able to obtain a lethal dose of THC by consuming somewhere between 1/3 of your body weight and 1500 lbs of marijuana (all at once).