alt.hn

2/23/2026 at 4:51:03 PM

Large study finds link between cannabis use in teens and psychosis later

 https://text.npr.org/nx-s1-5719338

by BostonFern

2/23/2026 at 5:41:51 PM

Marijuana legalization arguments were my first introduction to motivated reasoning. I was pretty inclined to agree that locking up non-violent drug offenders was a net-harm to society. But, the pro-legalization folks would argue patently crazy things: it cures cancer, the smoke isn't bad for you at all, there are no downsides! etc.

It seemed obvious to me that you could make a more realistic argument and just stick to an argument which states that due to drunk driving and domestic abuse, marijuana is less harmful overall than alcohol, but is treated as more dangerous. (and yes, the other side was a bit crazy too. "When you buy weed you're supporting the same terrorism that happened on 9/11")

Later research (such as this) has suggested a link between marijuana and psychosis, however the actual risk factors do seem difficult to nail down. (however, this is still a far cry from the claim that it's totally harmless)

What I ultimately learned is that in a pitched political battle, people actually damage their credibility because they're afraid to cede _any_ ground to the opposition, even when that means making unrealistic claims. A centrist (or just someone who is undecided) is not really taken in as much by these extremist argument, and to their eyes it damages the credibility of one or both sides.

by everdrive

2/23/2026 at 6:57:45 PM

Probably worth clarifying that when you say "But, the pro-legalization folks would..." you mean some stoners you met in college.

Because there are plenty of proponents who are not that... in fact 64% of Americans support making weed legal (2025), so it'd be really unfair to judge that movement based on those old experiences.

by zug_zug

2/23/2026 at 5:55:22 PM

I am firmly against marijuana legalization. This is partially because of this insanity of the pro-legalization arguments. When I would see friends/family that started smoking regularly become noticeably less intelligent while pro-legalization proponents would argue there are no negative side-effects, or people who were obviously compelled to smoke every day or as often as they could.... like some sort of addiction, while pro-legalization proponents argued it was totally not-addictive.

The anti-legalization side had a few odd arguments as well, and some old claims that were unfounded. So no hands were totally clean.

by ecshafer

2/23/2026 at 6:32:15 PM

> I am firmly against marijuana legalization. This is partially because of this insanity of the pro-legalization arguments.

this is also just motivated reasoning

The insanity of the fringe pro-legalization arguments has no bearing on whether legalization is a good idea or not.

> When I would see friends/family that started smoking regularly become noticeably less intelligent while pro-legalization proponents would argue there are no negative side-effects

This is also just ripe for cognitive bias which is why we should use science to understand these types of claims.

by estearum

2/23/2026 at 7:37:48 PM

Did the people you notice becoming less intelligent ever recover? I'm genuinely interested. My biggest regret in life is early years drug use, smoked my first joint at 13. Mdma 18. Cocaine late tewnties. I personally think marijuana might be worse than mdma but not by much. And cocaine is really bad for cardio vascular system, probably physically worst of all of them that I tried.

I think both mdma and marijuana cause anxiety and they mess with short term memory.

There doesn't seem to be a good answer to protecting kids from drugs. Heavily regulated legalisation might help or it might normalise drug use.

As an aside I personally think alcohol in very moderate use isn't really as harmful as other drugs. And is probably a net benefit for many. Even moderate use of illegal drugs seems to have bad affects on people.

Edit: added my thoughts on alcohol and something on cocaine use.

by pipes

2/23/2026 at 7:05:43 PM

I am firmly in favor of legalizing all drugs, except maybe antibiotics where overuse is causing harm for everyone.

The thing is, I 100% agree with your reasons for why it should be outlawed. I just think those are reasons to discourage using it, especially chronically.

However, I wholeheartedly believe the government should not have any say in how anyone lives their life, and treats their own body.

by dec0dedab0de

2/23/2026 at 9:16:11 PM

…just so long as the government remains responsible for clearing up the mess?

by dontwannahearit

2/23/2026 at 6:55:10 PM

I'm curious, do you also think alcohol and tobacco should be banned? I definitely believe that marijuana use can lead to negative consequences, but I still think it is less dangerous than either of those 2 substances.

by something765478

2/23/2026 at 7:01:24 PM

Yes I do.

by ecshafer

2/23/2026 at 9:19:12 PM

Can't have the billionaire sociopath fodder off in lala land... they must be 100% intelligent and productive to continue farming them resources

by whattheheckheck

2/23/2026 at 8:52:47 PM

>I am firmly against marijuana legalization.

Is there an argument or data that could be presented that _would_ change your mind?

by btreecat

2/23/2026 at 9:18:09 PM

Are you also firmly for alcohol abolition? What about gambling?

by whattheheckheck

2/23/2026 at 8:48:48 PM

But why is alcohol legal then? It has worse side effects and more collateral damage.

by croes

2/23/2026 at 6:39:34 PM

I never understand this line of thinking.

So the easiest way for an opposition to a good idea to get their way, is to go argue insane things on the opposite side?

Imagine if the oil industry starts paying people to go throw soup on paintings just to make the pro “let’s prevent climate change” people look stupid.

Oh. Wait.

by aaomidi

2/23/2026 at 6:50:38 PM

> But, the pro-legalization folks would argue patently crazy things: it cures cancer, the smoke isn't bad for you at all, there are no downsides! etc.

Who seriously claimed that it “cures cancer”? There have been some claims that it helps alleviate nausea associated with chemotherapy, which is quite reasonable and will likely be proved out by evidence over time.

Really … who genuinely claimed it “cures” cancer?

by isx726552

2/23/2026 at 10:07:44 PM

I've heard people who clearly had psychological issues claim things like this, but nobody actually credible. Problem is that people fall down rabbit holes that perpetually reinforce their own spiral.

The combination of actual drugs and grief and real underlying mental disorders is a powerful and scary mix.

by brailsafe

2/23/2026 at 6:54:27 PM

There are things like "Rick Sampson oil". I'm sure there are believers.

by troosevelt

2/23/2026 at 6:59:24 PM

I took it as more of an exaggeration of "medical marijuana" - a phrase you could rarely get away from in the 2000s.

by gosub100

2/23/2026 at 7:40:02 PM

> What I ultimately learned is that in a pitched political battle, people actually damage their credibility because they're afraid to cede _any_ ground to the opposition

This could be a person making a bad argument, or it could be that the individual is the opposition trying to poison the well. Cf COINTELPRO. Largely any movement has people with insane takes, and it's impossible to tell the difference between good and bad faith actors.

That, and sometimes people just aren't trying to be persuasive at all. It's extremely rare to actually see someone persuaded about anything political without enormous amount of effort, or more realistically a change in material interests.

by throwaway27448

2/23/2026 at 8:51:08 PM

TBF, if your paraphrasing others as "curing cancer" but what they claimed is "treats cancer" then the issue may be comprehension or activite listening.

Something to consider.

by btreecat

2/23/2026 at 6:08:22 PM

all legalization frameworks in the US already limit legal age of purchasing possession and consumption to 21 and over, specifically as a form of seeding ground to the opposition, specifically for the previously only anecdotal link to psychosis and underdeveloped minds of minors

by yieldcrv

2/23/2026 at 6:33:21 PM

It's weird to frame regulating cannabis the same way we regulate other recreational drugs as some kind of compromise. Is the ideal pro-cannabis situation that anyone can buy it at any age?

by AlexandrB

2/23/2026 at 6:40:15 PM

That’s not what that person was arguing?

by aaomidi

2/23/2026 at 6:45:40 PM

How so?

> all legalization frameworks in the US already limit legal age of purchasing possession and consumption to 21 and over, specifically as a form of seeding ground to the opposition

This plainly says that legal frameworks limit the age of consumption as a way of ceding ground to the opposition (implicitly the opposition to legalization). So I'm questioning, if there was no opposition to legalization, what would the legalization frameworks look like? Legal for anyone at any age?

Edit: To put it another way, what's the ground that has been ceded here?

by AlexandrB

2/23/2026 at 8:06:58 PM

This seems like a lot of different people voicing different opinions and talking past each other. Roughly, I think you're jumping into the middle of a hypothetical conversation that went like this:

Person A: "It's bad that we throw people in prison for pot, and use possession of pot as a subtext under which to harass people, perform warrantless searches, etc. We should just legalize it."

Person B: "But it might be bad for children and teenagers if they get access to it"

Person A: "Okay fine, we legalize it for people over the age of 21, happy now?"

Person A could be said to have compromised or ceded-ground to person B here, even though they themselves might actually not even disagree.

by smithoc

2/23/2026 at 6:58:42 PM

The freedom of 18-21 year olds to consume cannabis legally and not be threatened with violence from the state for doing so.

by Teever

2/23/2026 at 6:55:10 PM

I see. I missed that part sorry!

by aaomidi

2/23/2026 at 5:48:24 PM

>But, the pro-legalization folks would argue patently crazy things: it cures cancer, the smoke isn't bad for you at all, there are no downsides! etc.

Using the most anecdotally crazy people you met to suggest that the pro-legalization movement is crazy, is frankly, crazy. I'm very involved in legalization and I don't know anyone that is for legalization that thinks any of those things, never even heard anyone say such garbage. I think you may be cherry-picking the crazy here.

by leptons

2/23/2026 at 6:25:08 PM

>Using the most anecdotally crazy people you met to suggest that the pro-legalization movement is crazy, is frankly, crazy.

This was over 20 years ago, long before "nut-picking" became impossible to avoid. This is what I was hearing from my peers on my college campus. They may have had had extreme views, but this was long before modern social media surfaced only the craziest people for any given position.

>Using the most anecdotally crazy people you met to suggest that the pro-legalization movement is crazy, is frankly, crazy.

Also, I disagree with this characterization. I am not crazy, it was unnecessarily rude to suggest otherwise. I'm repeating the arguments I heard from my actual peers. I'm not just finding extremists on the internet and painting the whole group by its worst members.

by everdrive

2/23/2026 at 7:21:49 PM

>Also, I disagree with this characterization. I am not crazy, it was unnecessarily rude to suggest otherwise.

You suggested the legalization movement is "crazy", without context. We are far from it. But you used the craziest shit to paint us as "crazy", so you get what you give.

Your original comment stated:

>"But, the pro-legalization folks would argue patently crazy things:"

Nowhere did you mention your peers, you specifically said "the pro-legalization folks", meaning the whole group, up to the most prominent people. That's the only way we can take your original comment, so if you don't like being called out like this, then be a lot more specific and say it was only your crazy friend group that was crazy, making it very anecdotal and not overly broad.

by leptons

2/23/2026 at 5:54:46 PM

I know that I too say and heard those arguments a lot. You do yourside a disservice by claiming it doesn't exist

by bluGill

2/23/2026 at 6:26:14 PM

Good thing they didn't claim any such thing, then.

by andrewflnr

2/23/2026 at 6:39:44 PM

I don't think you can frame some of these arguments as belonging to a fringe minority. I remember watching an episode of "Penn & Teller's Bullshit"[1](2004) where they featured several pro-legalization advocates. These folks said or implied similar things (it's not bad for you, it helps cancer patients). These were not marginal "crazy" voices.

[1] https://en.wikipedia.org/wiki/List_of_Penn_%26_Teller:_Bulls...

by AlexandrB

2/23/2026 at 7:27:10 PM

"it helps cancer patients" is vastly different than "it cures cancer" which is what OP claimed he heard. And yes, it does help cancer patients as well as anyone else in pain. And the smoke is far less harmful than cigarette smoke, it has no additives at all (when grown in a controlled environment without pesticides). And you don't even need to smoke it, it can be ingested in an edible/pill, making most of the arguments against ingesting marijuana completely bogus.

by leptons

2/23/2026 at 6:44:06 PM

To be fair, the example they gave from the other side is far more fringe

> When you buy weed you're supporting the same terrorism that happened on 9/11

by buzzerbetrayed

2/23/2026 at 5:55:06 PM

Yes, what you observed is people making unrealistic and disingenuous responses in reply to equally unrealistic and disingenuous reefer madness type propaganda.

What happened is that the people making these disengenuous comments in bad faith did not realize that so many others would watch them and without understanding hte context woudl pick up those same disingenuous arguments and take them as truth.

This is all the long term consequences of allowing Reefer Madness tier propaganda be published and not repudiated immediately.

by Teever

2/23/2026 at 5:17:29 PM

"But by excluding teens who were already showing mental health symptoms, the new study points to a potential causal link between cannabis use and later mental health diagnoses. Additional research is needed to understand the link fully."

Hm, but this does not exclude the possibility that the being prone to mental illness comes with a little bit higher tendency to consume cannabis...

by ndr42

2/23/2026 at 5:51:31 PM

Similarly, cigarettes also have a very strong correlation with schizophrenia. Completely non-causal, but it's hard to find a non-hospitalized schizophrenic who does not smoke.

by ctrl-j

2/23/2026 at 8:35:43 PM

Let's not forget that many mental health "disorders" are just elaborate labels for having difficulty conforming to arbitrary cultural expectations.

by joquarky

2/23/2026 at 5:30:17 PM

When I read this article the other day I had the exact same thought. Is this simply correlation, or is it causation? Is teenage usage an indicator of a possible underlying condition that hasn’t fully manifest? Is it an early form of self medication?

by vforgione

2/23/2026 at 8:51:03 PM

And the only way to tell is to randomly split teenagers into two groups: cannabis vs. control. But no parent would give consent, so we will never know.

by M95D

2/23/2026 at 10:54:55 PM

Its a correlation result and not causation. The author makes a mistake, off course. Mental diseases have effects since deep in a young age and push for increased marijuana use, but also nicotine, benzos and, may be, obesity, aggressiveness, school dropout, parent's divorce, low vitD and a long list of possible factors. All these will be correlations.

by tsoukase

2/23/2026 at 5:26:51 PM

I used to read forums for schizophrenics (self disorders fascinate me, look the term up if you want to understand schizophrenia), and it was the consensus there that out of all the recreational drugs cannabis caused the greatest deterioration in one's mental state. Those are generally fairly sick people, but I don't think one can just ignore this signal. I personally went catatonic once after consumption, and I'm not schizophrenic at all. And that was in Amsterdam, so it wasn't some trash spiced up by a 17-years old dealer with whatever he found in his grandma's medical cabinet.

by H8crilA

2/23/2026 at 6:11:19 PM

I don’t know what things are like in Amsterdam, but weed being “high quality” is not a good thing. The potency has skyrocketed over the past few decades. It’s like saying you went to Amsterdam to drink alcohol for the first time and had a bottle of tequila and passed out and puked; the fact that it was high quality tequila does not mean it’s better than a low quality glass of wine or beer. The issue is the doses are way too high.

by orionsbelt

2/23/2026 at 9:37:07 PM

Continuing the analogy, it does mean that they can blame the alcohol and not, say, rohypnol for their outcomes.

by ProjectArcturis

2/23/2026 at 9:06:52 PM

But imagine the kind of self-selection you'd find on such a forum. Furthermore, it's been long known that cannabis use can trigger schizophrenia in those who were already genetically predisposed to such. Your observation and the OP are not news worthy, imo. Bad outcomes have also been observed when combined with immature brains.

But for healthy adults, countless have used cannabis for generations without experiencing harmful reactions.

This one's my favorite: https://thereitis.org/mr-x-by-carl-sagan/

by swed420

2/23/2026 at 5:40:43 PM

> it was the consensus there that out of all the recreational drugs cannabis caused the greatest deterioration in one's mental state

Methamphetamine and PCP might take issue with this statement.

by galleywest200

2/23/2026 at 6:09:23 PM

Weed can make you paranoid, every smoker knows this. It is patently obvious that it could trigger something worse, too, if you are already sensitive.

I think only young people in their weed honeymoon phase get defensive about this.

by sfjailbird

2/23/2026 at 6:06:55 PM

Problem with recreational marijuana is that it’s so insanely strong. It would be like giving a child 190 proof azeotropic grain alcohol and being shocked that they immediately vomit. I can’t smoke pot - it’s just too strong.

I’ll admit to feeling a bit dumber and foggier after a few weeks of ingesting cannabis nightly though. That’s a real thing.

by selectodude

2/23/2026 at 7:00:28 PM

I've heard that the reason why marijuana is so strong is because it was illegal. The sellers wanted to have stronger weed to make it easier to transport; much like how during prohibition, people would prefer to import distilled alcohol, instead of beer.

by something765478

2/23/2026 at 8:58:48 PM

Same logic applies to explain the popularity of fentanyl.

by akramachamarei

2/23/2026 at 9:39:25 PM

It's weird that people argue it's better for you to consume extra burned plant material to get to the same level of high-ness. If it's stronger, people just use less.

by ProjectArcturis

2/23/2026 at 6:13:05 PM

For what's it worth for an N=1 study I watched a relative's young family fall apart because of cannabis induced psychosis. They had two young kids, husband was smoking pot recreationally (not sure how long he was doing that) but at some point he started hearing aliens talking to him from the cracks in the wall. Naturally you can't just keep doing all the regular life and family stuff when you have more pressing issues like visitors from out of space in the walls talking about attacking earth.

I am not saying anyone should or should not use these substances, but that was enough of a lesson for me to know never to touch that stuff.

by rdtsc

2/23/2026 at 6:21:35 PM

So I'm sorry that happened to your friend...

But also let's remember that there are tens of million Americans using weed products (legally in many states) who are having a great time with it. Which is why we need large-scale studies like this, and why any individual anecdote shouldn't offset a large study.

by zug_zug

2/23/2026 at 6:36:47 PM

Whether or not cannabis makes psychosis more likely isn't proven, but your N=1 study illustrates how bad it often is. People should know that psychosis isn't just having some weird ideas, but often destroys lives and families.

by tlb

2/23/2026 at 6:18:33 PM

There is no established causal link between the two. Cannabis is so ubiquitous that it is often the case that people with underlying psychiatric problems find it calms them and then blame cannabis for it if they get worse, because that's saving face in a twisted way.

Link is not the same as "it causes it".

by varispeed

2/23/2026 at 9:18:34 PM

In my subjective experience cannabis does tend to nudge some part of the brain into edit mode. What happens afterwords depends on the person.

For me it upended a lot of my alignment with the contemporary consensus morality. Before marijuana I had a sense that the morality wasn’t actually well foundationed, or at least it was equivalent to a religion in that respect, but my mind seemed to avoid thinking about it too much. With marijuana my mind freely went there, and I think a lot of my prior beliefs about the world and social systems ended up being altered.

I haven’t ended up with any diagnosed conditions, but it is inconvenient to have beliefs that are quite different from the societal default, even though in my case I do believe that my way of seeing morality is significantly more accurate on a technical basis than the consensus view. And I suspect this wouldn’t have happened without any marijuana.

I can definitely see how someone with a less analytically oriented mindset could end up going off in weird directions and writing that as a legitimate belief while in edit mode.

We definitely need studies to properly characterize what exactly this edit mode is, but I am not too skeptical about there being some kind of causal link between marijuana and going off the rails mentally, in some individuals and in some environmental conditions.

by pfannkuchen

2/23/2026 at 6:21:40 PM

Good point, you may very well be right. But seeing how that tragedy unfolded was enough to convince me at least to never consider it, just in case there is a causal effect.

by rdtsc

2/23/2026 at 10:54:09 PM

[dead]

by OGEnthusiast

2/23/2026 at 6:09:32 PM

I’m in two minds about this, on the one hand I spent a week with acute psychosis after smoking weed when I was a teenager, so I really think people have to be more aware of the risks. On the other hand, I think it’s clear that this is not a perfect research design, and there are obvious possible confounds.

What about legalisation as a natural experiment? Has anyone done diff-in-diffs of US states and simply looked at eg mental health diagnoses or hospital admissions?

by dash2

2/23/2026 at 6:16:02 PM

So just for context

"Based on data from 2023–2025, approximately 15% to 17% of American adults currently consume cannabis." - Gallup

So though this may be technically true in some sense, it should also be understood that if cannabis had any major immediate drastic effects we would have noticed them decades ago. Perhaps weed, like alcohol, needs a legal minimum age of 21.

by zug_zug

2/23/2026 at 6:41:03 PM

> Perhaps weed, like alcohol, needs a legal minimum age of 21.

Generally, it already does have a legal minimum age of 21.

by in-silico

2/23/2026 at 6:19:15 PM

> major immediate drastic effects

Very few things in life pass that test, which is why we have research studies

by intrasight

2/23/2026 at 6:34:30 PM

Right we have studies, and they are 30 page documents that only academics read, and so they get poorly summarized by articles that try to make them sound more noteworthy than they are. Usually by saying "X linked to Y" without establishing causality or even if that link is a significant risk (is it a .1% increase in risk?)

When it's a drug more than 10% of the US population uses, we can immediately say the risk increase can't really be that big or we'd have noticed it by now.

Edit: after looking at the paper, it looks like among the weed group the prevalence is roughly twice as high -- so instead of 1/100 having psychotic issue it'd be 2/100... and again for people who used when they were 13-17 year olds, which is underage in every state.

So you could frame that as doubling the risk OMG, or a 1 percentage point increase in risk, or it could all just be self-medicating, we really don't know much. Probably still safer than alcohol.

by zug_zug

2/23/2026 at 6:54:58 PM

Part of the issue with legal weed is it's much like if all alcohol was sold as minorly different varieties of Everclear at 150+ ABV, and brands primary boast was just how potent and alcoholic their mix is. It doesn't encourage appropriate usage and IIRC many of these cases of psychosis are from consuming high THC products 24/7 for weeks/months/years on end.

If anyone is curious, check out brands like Rove, Dompen, Care By Design, which offer THC pens at very low dosage. They're frustratingly undermarketed and understocked, but as a CA resident I buy and use pens that are ~4% THC (rather than 90%+). A single puff occasionally after the kids go to sleep - the effect is marginally psychoactive, scratches the itch for "relaxation without impairment", helps me sleep restfully.

Completely different experience to high THC products. If you compare the literal amount of THC consumed, it's an almost 20x reduction. It's literally the equivalent to having a half glass of wine instead of lining up 10 shots.

by extr

2/23/2026 at 7:00:42 PM

I use gummies, ~4-5mg THC (ideally with some of the other TH- chemicals in it), deliberately kept my tolerance low so it doesn’t get more expensive (and I almost only use it for sleep, purely “fun” use is maybe a couple days a year). Take in the evening, start an MST3K episode about an hour later, really enjoy the back half of it, go to bed and fall asleep instantly, wake up feeling like a million bucks. Perfect evening.

by bubblewand

2/23/2026 at 9:02:49 PM

In my teens/20s, I would have advocated for legalization of marijuana and thought any argument against it was some antiquated, puritanical nonsense.

In the decade+ since, there's no way I'd do so.

I know three personal friends that are long time (allegedly not addicted) heavy marijuana users that all suffer from Cannabinoid hyperemesis syndrome to the extent that it's effected their daily lives substantially.

Two of the aforementioned are roughly my age, and are half as bright as they were as teens. Neither of them can follow a train of thought particularly well and are difficult to hold conversations with.

How much of this is attributable to how much more powerful "modern" strains (or whatever the geo-engineered differences are) is unknown, but I can't imagine it's not a factor. This is not the dopey "get stoned and play XBox and eat a whole pizza" stuff we had in the 00s.

I'm sure there's plenty of counterexamples or something, but my perspective on this has completely changed, influenced by examples like this.

by nyarlathotep_

2/23/2026 at 9:41:59 PM

Do you think their lives would be substantially better if they had been arrested and sentenced to lengthy prison terms?

Alcohol can have a well-documented destructive effect on people's lives. Should it also be made illegal?

by ProjectArcturis

2/23/2026 at 5:35:13 PM

The correlation used to cite heavy (daily repeated administration across the day; what the kids call "the chronic.") But now its just any degree of use.

I should add that I happen to know of more than one heavy user who subsequently progressed to Schizophrenia or bipolar disorders so I don't personally doubt the cause and effect.

But this blanket correlation seems to me to be overbroad.

by anjel

2/23/2026 at 11:13:46 PM

Marijuana certainly doesn't cause bipolar disorder, but it definitely can affect or potentially induce a manic state. Of course bipolar people are already known to self medicate heavily and use a lot more drugs in general, and drugs are not the only way for them to self induce mania.

by AngryData

2/23/2026 at 6:49:09 PM

From the article: "Teens who reported using cannabis had twice the risk of developing two serious mental illnesses: bipolar, which manifests as alternating episodes of depression and mania, and psychotic disorders, such as schizophrenia which involve a break with reality."

That 2X factor is big. If it was something like 10% - 20%, it might be noise or some other factor, but that big a number is real.

by Animats

2/23/2026 at 6:44:02 PM

Not a skeptic, but I've seen these studies for a while. Do we have any idea what the mechanism could be?

by avoutos

2/23/2026 at 6:47:32 PM

Since when does NPR use generic buzzy words like "huge" in their title ?

by mentalgear

2/23/2026 at 6:49:39 PM

I always see whenever a study mentions risks of cannabis, it's always met with "it only happens to those with innate tendencies" but then I ask them do they even understand what those effects are? Do we understand what schizophrenia and psychosis is, it's exact mechanisms?

Western medicine can't even explain any of these ailments, where it comes from, how it happens, what triggers it but so many cannabis users shield and attack any new research or study that questions the risks of cannabis for the young.

If it truly is harmless then are those same people suggesting that they light up a joint with their children ? Doctors hand out edibles when they catch a cold or can't sleep?

While I do think there are deeply helpful properties of cannabis we are still early, new research is only beginning to come out as it gets scrutiny. It took us many decades to learn the harmful effects of tobacco while for a long time everybody just shrugged it off as conspiracy. It took heavy lobbying from those that stood to gain most to delay the truth of the product they were selling and a lot more political will from the other side to warn the public.

Right now what worries me is the marriage of profiteering and political ideology that have neutralized the similar movement that existed around tobacco and alcohol in the Western hemisphere. Many see money to be made or their political statement that they will defend vigorously. The real risks that I see is raising the THC % content to extreme levels for chronic users who built a large tolerance through long term habitual use and claim they aren't addicted, proliferation of white/grey dispensaries that make it even more accessible to the young. This really needs to be addressed when we don't even understand the mechanisms or can reliably explain the after effects of those risks coming to fruition.

by agentifysh

2/23/2026 at 8:01:46 PM

I think this is a classic case of correlation does not imply causation. As someone that has known these people, and I does smoke as an adult, I would interpret that as people who are struggling with mental illness symptoms turn to weed as an outlet. Especially when we take it with the wider literature on drug abuse and mental illness any practitioner worth their salt knows mental illness makes drug abuse more likely and yes then the two affect one another which is why rehab is usually a big part of the hospitalization process. But what I don't want to see is more moral panic so we can renew the war on drugs which as always should really be the war on poverty and mental health issues.

by MantisShrimp90

2/23/2026 at 7:05:02 PM

They do not compare to the baseline population correctly. Roughly 1% of all people are susceptible to schizophrenia, and up to around 4% schizophrenia, extreme bipolar, and other conditions that can result in psychotic episodes or extreme outcomes.

Drug use among vulnerable populations increases the risk of psychotic episodes, but does not increase the risk of developing those conditions. There is no difference in the rate of extreme psychological outcomes among drug users and non-drug users, and in fact, this study reinforces that observation - only 4,000 of 460,000 had those negative outcomes. Over the next 20 years, it's extrmeely likely that another 600-1000 will develop schizophrenia, even abstaining from drugs entirely. Drug use can trigger a psychotic episode and result in long term schizophrenia; by the time you turn 45, however, your odds of a schizophrenic break drop to almost 0.

The worst part of drug use and mental health outcomes is that it can rob people of normal years of life, and rarely, result in schizophrenic or other psychotic conditions being triggered when they might never have been. However, this is not just marijuana or other illegal drugs, but alcohol, caffeine, trauma or intense stress, and even chronic health issues can have the same outcome.

This study also fails to account for the confounding fact that people with mental health issues often pursue mind altering drugs in order to self medicate. People with bad conditions in life, especially younger, undergo extreme stress and are exposed to illicit substances much more readily than those in otherwise stable and healthy conditions.

The results and methodology are flawed, and the conclusions being drawn have little to no relationship with reality.

It comes down to susceptibility - genetics and health conditions play into this. Consult a doctor, and if you have risk factors, live your life accordingly.

If you don't have risk factors for schizophrenia, drug use will not suddenly put you at risk of developing it. Marijuana or other recreational drug use will not cause you to have a psychotic episode. If you do have risk factors, then you're twice as likely to have an episode by using drugs or experiencing other triggers than otherwise.

For those who are susceptible, your relative risk of psychotic episodes and mental breakdown double under mairjuana and other substance use.

For those who are not susceptible, your absolute risk of psychotic episodes and mental breakdown remain near 0. Drugs don't induce these conditions (except in the case of extreme stimulant abuse, and possibly extreme psychedelics outcomes, although getting fried by psychedelics isn't really the same thing as psychosis. Lots of high function deadheads survived some truly harrowing levels of substance use and are best characterized as "weird".)

It'd be nice if the media could distinguish between relative and absolute risk rates and communicate the difference effectively. It'd be even nicer if researchers and publishers didn't chase clickbaity results like this and mischaracterize things like relative and absolute risk for profit.

by observationist

2/23/2026 at 6:50:18 PM

4000 out of 460000, that's about 0.8% or so? At the face of it, it doesn't seem a lot higher than the 3% lifetime risk of psychosis and whatever it is for bipolar disorder.

To me it doesn't seem like they control much for confounding factors, or the possibility that young people who might develop psychiatric illness could also be more drug seeking or irresponsible in their drug use.

by cess11

2/23/2026 at 6:06:50 PM

As well as the correlation/causation problem...

From what I hear, cannabis on sale today is rather stronger than when I was young. That sounds bad to me. Curiously I see this as a pro-legalization arguement, if it were available in a shop I could select a mild flavour, rather than the skunk that the criminals grew, and is all that is on offer

by jimnotgym

2/23/2026 at 6:23:42 PM

I've heard that too but if you go to any dispensary you can get a gummy with an exact dosage of THC and CBD on the label. It's actually a much superior system now to backchannel dried flower.

by zug_zug

2/23/2026 at 6:33:15 PM

Yeah but it’s hard to even find a 5mg these days. Most are 10 or 20 by me. Edibles aren’t immune from the increase in dosage.

Edit: also these aren’t pharma companies. It may have gotten better but I think manufacturing consistency isn’t good either. Highest I’ve ever been was from a single “2.5 mg”

by interestpiqued

2/23/2026 at 6:41:29 PM

And in states like NY, 5mg is standard.

by aaomidi

2/23/2026 at 6:40:39 PM

Why not cut it in half?

by direwolf20

2/23/2026 at 6:40:49 PM

Yeah that's what I do and it works great for me

by zug_zug

2/23/2026 at 5:26:37 PM

Unless you blind this, I’m not sure it’s possible to get past the correlation or causation problem. Weed use is not yet so destigmatized for teens that usage itself is not a marker of deviance (in the math sense, not any kind of judgement).

by roughly

2/23/2026 at 5:16:35 PM

What a strange study. Only less than 1% even developed these conditions.

They excluded people with a mental health diagnosis, and their data for already having symptoms was having a diagnosis?

Why do they assume this shows marihuana causes mental disorders, as opposed to being undiagnosed whilst already showing symptoms leads to self medication, for example?

I’m sorry, but most psychology research is just so incredibly badly done.

by moi2388

2/23/2026 at 5:41:14 PM

The experiment to get to the root of this is forbidden. They’d have to perform double blind (kind of a fools errand when being high is so obvious) experiment where they gave matched patients and controls either weed or placebo. Then they’d measure effects long term with enough of a sample size to overpower latent factors.

But this study will never be approved for obvious reasons so we will never know one way or another.

by kjkjadksj

2/23/2026 at 8:40:43 PM

Science has to start somewhere. Actually proving a causation is hard and expensive and usually needs to be very targeted. You need these kind of feeler studies to find promising links to target for further research.

This is why science is so much about standing on the shoulders of giants.

It is wrong for journalists to report these low rigor, survey studies as the meaningful results they always seem to report, but for some reason Women's Health can keep saying "Chocolate causes cancer actually chocolate cures cancer actually chocolate has no effect on cancer actually...." for decades and people don't stop buying it and instead insist that the scientists are the ones lying

by mrguyorama

2/23/2026 at 5:26:42 PM

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by gtsop

2/23/2026 at 5:35:29 PM

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by gtsop