[vasco]

> Most physicians will agree that cannabis is fairly harmless.

If you read some papers on the subject it should be plenty apparent that it has adverse effects on the development of young adults, as well as long term use by anyone, particularly of recent high-potency strains.

It's not as bad as other drugs (heroine), and it's worse than others (coffee), but it's not harmless. I'm far from being a prohibitionist, and live somewhere that has (I think) sensible policies (The Netherlands), but to simply put that it's "fairly harmless" as something most physicians agree with is not true. I'd say it's similar to alcohol in terms of its moderate use being possible in a working society - albeit with some negative outcomes for people that overdo it, or do it too early in life.

Edit: there's lots of discussion below about if the studies that exist are trustworthy or not, but since anyone can google for studies, I'll leave a different recommendation to check out the r/Leaves subreddit, and read some first hand accounts of long term and heavy users. It's at least a different type of source and you can make up your own mind about what real users say about it, in case you never encountered it before.

[achileas]

I have a graduate degree in neuroscience, worked with colleagues who focused on psychopharmacology for their research, and many of my friends and neighbors are biologists of various stripes, including still-active neuroscientists, as well as epidemiologists, and clinicians. They all agree cannabis is fairly harmless, and would outright laugh you out of the room if you compared its negative effects (either in the individual or to society) to alcohol.

Clinicians aren’t the ones to go to for harms anyways, they’re largely not doing the research at any level.

[Saline9515]

What is the harmless dose? One join per year? Per month? Per week? Per day? Several per day, as I often saw in my youth? My father was addicted to cannabis, I can tell you that it reduces a lot ones' life outcomes and has consequences on your family.

[zikduruqe]

"Stan, the truth is marijuana probably isn't gonna make you kill people, and it most likely isn't gonna fund terrorism, but… well, son, pot makes you feel fine with being bored. And it's when you're bored that you should be learning some new skill or discovering some new science or being creative. If you smoke pot you may grow up to find out that you aren't good at anything." - Randy Marsh, South Park (https://en.wikipedia.org/wiki/My_Future_Self_'n'_Me)

[dzonga]

that's the part they leave out. the cannabis they test in the labs is probably 5mg. The flower sold in the streets is over 20mg.

I have seen people go into psychosis from weed. & no it wasn't laced. I have seen my gf's dad go from a non-smoker to rolling a blunt every hour. I have had friends drop out of college due to weed.

[watwut]

If you are alcoholic enough, alcohol withdrawal can literally kill you. Likewise, consequences on family and your own outcomes are massive even before that stage.

[vasco]

What a neighborhood where you have deep discussions about psychopharmacology research with your neighbors, incredible.

[varjag]

Alcoholism is certainly destructive, but if you have predisposition to schizophrenia you really better off with drinking than smoking pot.

[xhkkffbf]

Unfortunately, people with predispositions like that are even more drawn to marijuana (and other drugs). It's a form of self-medication-- that sometimes goes wrong.

[NemoNobody]

That's hilarious

[bombi]

Schizophrenia is the result of deficiency (and dependency) of vitamin B3, aka niacin. Adam Hoffer's therapy cured thousands

[andai]

For a while it was unclear if the link between cannabis and psychosis was correlation or causation, but causation was ultimately established. It seems to be a relatively small percentage of the population that experience such things, but that's largely the same part of the population prone to heavy, chronic cannabis consumption in the first place.

So I just wanted to add that for a subset of the population, the risks are several orders of magnitude more serious than "lost a few IQ points", as many people are not able to resume normal life (nor indeed, a normal experience of reality) after a psychotic experience.

That being said, I do support legalization, since the alternatives are worse. I just also support people being well informed, and aware that while they're probably not in that 2%, there's only one way to find out, and you really, really don't want to find out.

[MavisBacon]

edited to specify that I was addressing adult use. Agreed use in adolescence or even younger can be problematic. I also think that there isn't enough discussion around the impact of cannabis on cognition. Here in the U.S., though, as far as medical consensus there truly is not very much concern around cannabis use. A report found that there is limited evidence of the harms of cannabis, and ample evidence of medical use-cases- published by the National Academies of Sciences, Engineering, and Medicine (NASEM) in 2017

Worth noting our current overdose crisis and general lack of health care in many parts of the country, now the under-prescription of controlled medications- which all helps shift a lot of these dynamics in a direction that might not be seen in other parts of the world.

[svardilfari]

I'd challenge you to read those results again. They admit to the evidence for health effects being elusive (due to limited or no robust studies), yet there is still enough evidence to summarize the following:

"

There is substantial evidence of a statistical association between cannabis use and:

The development of schizophrenia or other psychoses, with the highest risk among the most frequent users (12-1) There is moderate evidence of a statistical association between cannabis use and:

Better cognitive performance among individuals with psychotic disorders and a history of cannabis use (12-2a) Increased symptoms of mania and hypomania in individuals diagnosed with bipolar disorders (regular cannabis use) (12-4) A small increased risk for the development of depressive disorders (12-5) Increased incidence of suicidal ideation and suicide attempts with a higher incidence among heavier users (12-7a) Increased incidence of suicide completion (12-7b) Increased incidence of social anxiety disorder (regular cannabis use) (12-8b)"

National Academies of Sciences, Engineering, and Medicine. 2017. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington, DC: The National Academies Press. https://doi.org/10.17226/24625.

I would warrant that these summaries should be a concern for anyone using cannabis and that blanket statements regarding the overall tone and summation of the report negating health effects of cannabis is somewhat misguided.

[achileas]

None of which are causal associations. Given the millennia-long history of cannabis use to self-medicate, and lack of evidence (not without trying!) for a biological mechanism of any of this, it’s probably safe to assume this is largely people with an issue (or a proto-issue) self-medicating.

[kaonwarb]

Your argument appears to be jumping from (lack of causal associations) to (assumption that causality is in the opposite direction).

[pclmulqdq]

This has also been studied more since 2017 now that there are a lot more people taking cannabis, and many of these links have been confirmed, although some have not.

It has also been confirmed that heavy use of marijuana has negative effects on cognitive performance and short-term memory even in adults, although these symptoms go away after you stop using.

[Me000]

I think the evidence is closer to “completely harmless” than “mostly harmless” there’s literally never been a reproducible study that shows cannabis is in any way “bad for you.”

[SkyPuncher]

My wife is a psychiatrist. It’s not unheard of for her to have to deal with cannabis induced psychosis.

One of the more challenging things with cannabis is it can trigger people who are more predisposed to issues. Some of these things can stick around for a while, after an initial incident. Compared to something, like alcohol, cannabis based issues don’t only affect heavy or long term users. You might just be the unlucky person that cannabis doesn’t jive with.

That being said, I think she largely thinks legal cannabis is good. She’s seen recovered alcoholics who’ve turned to cannabis as their outlet without killing their liver and destroying their body.

However, acting like there are no risks to cannabis is not helping anyone.

[herval]

The negative effect on brain development of young people has been extensively studied and proven, by many different studies across many different countries.

[tokai]

And the GP was clearly stating that it was about adults. You're either arguing in bad faith or not paying attention.

[herval]

what's an adult for you? Studies show effects on people of up to 25 years of age.