It's a hard one. How do you measure the true harm of a substance? Even weighing up alcohol vs weed is way beyond my comprehension. All I can say is I've got a soft spot for smoking weed but despair at the problems I've seen it cause, upto and including schizo-affective disorder. One thing that bothers me about it is that I've seen too many people smoke it, then later violently scream at members of their family. The guy next door does this. Get fucked up at night, plays zombie games... next day fly off the handle at his son over the smallest thing. He's a fucking arsehole anyway, but it definitely makes things worse. It's probably linked to the way weed suppresses frontal cortex activity, removing 'internal' inhibitions, allowing our thoughts to go in directions they normally wouldn't, and amplifying our experiences (wereas alcohol's disinhibitory effect is more of a body/libido thing). CBD's present in the weed balance this out by making a person emotionally passive. But once the weed wears off, that effect is quickly gone, and the serotonin and dopamine levels fall to unstable levels.... I reckon some of that disinhibition still persists, meaning people can be really fucking unpleasant in a disinhibited way, taken over by underlying negative emotions.
Obviously alcohol's disinhibitory effect does sometimes lead to violence, random and domestic, but that's generally short lived. I don't think I've seen people act like this because of a hangover. They generally isolate themselves and are very quiet for a few hours. I reckon the weed thing affects another group of people, and we know the effects wear off much more slowly. We know traces of the drug remain in the system for a very long time indeed. Perhaps one difference between alcohol and weed is that the only psychoactive components of alcoholic drinks is the ethanol (with perhaps a touch of caffeine)... whereas weed can be any mix of dozens of related components, which have differing neurological actions, leading to different psychological effects... each of which may wear off at a different rate, and each of which might affect individuals in a different way.
The rebound violent reactions wouldn't be caught in any studies measuring psychosis, but I suspect they could be seen as a mild form of it. Low serotonin means certain feelings and thoughts are experienced, and those that are, are felt much more rawly. The frontal cortext is still suppressed, and can't 'catch' or wind them down properly, and they escalate out of control in a flash. I also suspect that the short-lived anti-psychotic effects of CBD lead to a down-regulation of naturally occuring anti-psychotics.
I am not saying this is how weed affects most people.... or even that most users will suffer borderline significant negative effects... but I do think that the varying effects and durations of the many psychoactive compounds might lead to other problems that are hard to observe, and that some of these will completely blindside the affected individual.
Anyway, it's just my over-complicated and under-substantiated theory. YMMV
The reason why people take drugs is because they alter the way that you feel, be that better or just different.
I don't agree with everything this video says on the subject, but it was an interesting watch.
