> “Compared to non-users, regular cannabis users were more likely to engage in high-risk alcohol consumption, smoke tobacco, use other illicit drugs and not be in a relationship at age 35,” Dr Chan said.
[...] They were also at higher risk of depression and less likely to have a paid job.
> “Overall, regular use of cannabis [...] was found to have harmful consequences, regardless of the age people began using it.”
I am skeptical that this study is actually representative of the effects of cannabis, and does not instead depend on other, highly correlated effects, which are then presented as the reason. From my general (non-user) perspective, I would assume that there is probably a bias towards groups of people who have a higher chance to use substances in general, or live in a comparatively poor environment.
For example: Children of smokers often become smokers themselves (as numerous credible studies show). If they now start with cannabis, they would be included as the victims of cannabis in the discussed study. However, the causality is probably reversed here.
> Compared to non-users, regular cannabis users were more likely to ... not be in a relationship at age 35
In 20 years of various relationships, the only girlfriend who didn’t request that I quit smoking weed was extremely naughty and experimented with all kinds of substances, as she completed her residency at a children’s hospital. She married someone with more money, God help him.
So, it doesn’t surprise me that people not in a relationship tend to smoke more weed.
> It compared adulthood life outcomes at age 35, including alcohol use, tobacco smoking, illicit drug use, relationship status, financial hardship, depression, anxiety and employment status.
As always, remember that correlation is not causation.
For example, maybe people with depression or anxiety are using cannabis to self-medicate.
Additionally:
> The research project followed 1792 Australian high school students aged 15 in 1992, investigating patterns of cannabis use across 20 years.
So, mix in the confounding factor of it not being legal during those years.
Keep in mind that correlation doesn't prove causation, but it does go along with it. Any time you find correlation, something goes along with it. Maybe A causes B. Maybe B causes A. Maybe A and B have a common cause C. Each of those is interesting, even if you don't know which is which from just the correlation.
Consider if the data had fallen out the other way: if there was no correlation between these measures of harm and cannabis use, that would have been evidence of a lack of harm from cannabis use.
So even if you can't draw any strong conclusions from this study, it's still an interesting data point.
Yeah, there are quite a lot of evidence hinting at cannabis being bad for you long term, especially when used as a kid. Doesn't mean it should be illegal, but just like with alcohol or smoking it almost surely isn't good for you and trying to ignore that doesn't do you any good.
Was glad to be the opposite of this study, been consuming cannabis since 13-14 pretty much daily, a few breaks here there maybe 6 months total not consuming in that time span. Happily married with a kid and full time job. BUT I will say it became a crutch and a money sink.
Heading into my 40s with the plan to stop daily consumption, currently only have CBD strains in the house, my friend likes to the call it methadone for pot heads. Wish me luck.
The one person from our group of friends is schizophrenic and it was heavy cocaine use that seemed to have opened that pandoras box. He's many many years sober and steady eddy on his medication doing really well.
Another friend is bipolar schizoaffective and his relationship with cannabis is toxic at best. He knows it's the last thing he should be indulging in, but unfortunately in his mind he can't find any other way to fall asleep. Heavy indica strains tend to bring on mania for him.
> He knows it's the last thing he should be indulging in, but unfortunately in his mind he can't find any other way to fall asleep.
I used to use indica to sleep, due to absurd levels of restless leg that only kick in as soon as I lie down. Then a physician friend recommended trazodone.
I really enjoyed being able to dream again. I hadn't quite noticed that I had basically entirely stopped dreaming when using pot. And mostly, I like being able to smoke purely recreationally and sporadically, not relying on it medicinally and regularly.
Good luck to you. I'm 15 years ahead of you, had some friends in similar situations.
A couple of my friends have since died (caused by substance abuse). I truly believe human beings are best off with fewer recreational chemicals in their bodies.
>The one person from our group of friends is schizophrenic and it was heavy cocaine use that seemed to have opened that pandoras box.
Opened the box indeed. I wonder how many latent schizophrenics never experience symptoms thanks to never hitting a precipitating event, pharmaceutical or otherwise.
If you're on HN, chances are, you're not very correlated to the sample from this research study... which looks entirely at correlation, not causation. I'm interested in a long-term study that identifies real differences in health outcomes, not just population bias.
In the 1970s there was the Shaffer (sp?) study in Jamacia.
Since then there have been hundreds of studies.
Generally cannabis, and recreational drugs generally, have not much in the way of negative measurable effects.
Remember it is only good drugs that have to be banned: There are no laws (generally) against Atrpine (datura), digitalis (foxglove) et. el. Just the good, fun, safe drugs have to have laws against them.
> “This is particularly important for jurisdictions that have already legalised recreational cannabis, such as Canada and some US states.”
What a joke. How many studies have been done on the negative effects of alcohol with no comment on the "importance for countries who have already legalised" recreational alcohol use?
There's really nothing to discuss around this article. None of the point is new (Cannabis users in where it is illegal also showed strong correlation with other substance use), The strong claims are click-bait:
>not be in a relationship at age 35
and it's light on any details or insight. It's a ridiculous hit piece with nothing but academic resume padding, but from none other than professors, that get amplified by shoddy journalism. Probably with some ulterior ideological motives (for funding maybe?)
Most of all: It's not tech related. Why is this voted up so much?
I think not being in a relationship at 35 is like BMI: it’s probably a good enough measure for most people, and the outliers can just excuse themselves.
Single high value people at age 35 describes most long term expats I meet at the beach who have very little in common with most of the population.
Btw look around, this isn’t just a tech forum that wants to debate JS and OO all day (just half of every day). It’s on the front page because we like talking about drugs. Though let me be the first to point out to you that drugs are a permanent passenger in the larger culture of tech.
The contrast between the discussions around the social media study posted earlier[1] and this study is pretty interesting. I guess it's only causal if it confirms one's priors?
I can't see how this study is measuring the harms of regular cannabis use. This is measuring how many people who experienced problems in their early 20s dealt with them. More depression / hard drug use / more likely to take weed daily / etc.
Other headlines they could have used.
Being a relationship doesn't affect your depression / hard drug use / etc
This really rings true to me. I've consumed cannabis over the past decade varying degrees of regularly, typically in cycles of a few months of daily usage followed by a few months of very infrequent usage.
I've found when I am in a daily usage phase, I am overall more lethargic, less motivated at work, less motivated at fitness, and less motivated to go on dates. These problems don't entirely clear up when I am outside of a daily usage phase, but progress made in those areas tends to erode. This doesn't dramatically affect my life, I am certainly functional and overall productive at work and in my social life, but at the same time the findings make sense to me.
"By the mid‐30s, both young‐adult and adolescent‐onset regular users were more likely than minimal/non‐users (63.5%) to have used other illicit drugs (odds ratio [OR] > 20.4), be a high‐risk alcohol drinker (OR > 3.7), smoked daily (OR > 7.2) and less likely to be in relationships (OR < 0.4)."
So this study basically shows that cannabis users are more likely to experiment with other drugs -- meanwhile, the "less likely to be in relationships" factor might not even be statistically significant (the OR is < 0.4). I'm not sure how one defines "anti-social behaviours" either, other than conforming into some societal box.
Or maybe the causality is reversed, and it is not that weed causes higher alcohol consumption but rather people who would choose to consume more alcohol would also be more likely to choose to consume more weed? Maybe there is no causality and only correlation? Has this been explained in the article?
Maybe having paid job makes you use weed less (for possible consequences of being high at work)?
Maybe cannabis doesn't cause depression but rather it is just correlated for some other unknown reason?
That's again, very poorly written article by a confused author who does not understand causality and correlation.
Something ironic about U of 'Queensland' pushing out a study which could be used in justifying the long running prohibition and demonization of a medicinal plant by state authorities.
For our non-Australian readers in the audience, Queensland is generally considered the most conservative/least progressive state in the country, with the police service in particular embroiled in endless scandals around corruption, racism, violence, etc.
"Consequences" sure does imply causation, but this doesn't say that. It says "linked to negative life outcomes" which sounds a lot more like correlation to me.
If you replace cannabis in the title with alcohol or tobacco everyone would have said "duh.." and move on. The difference is that the legalization of marijuana is a hotly debated subject so people's opinion on the health effects seems to be more affected by their position on legalization.
If you showed this article to a Dutch person, they'll probably just say "duh.." then continue smoking their weed instead of tearing apart this article like a lot of people here.
Going over the background of who did the study, the abstract, and their assertions, it appears they've made the classic mistake of correlation = causation. Nothing in their study supports their assertion of a casual link.
Based on their alarmist and projective tone, they probably made this error on purpose in order to push an agenda for their own benefit. The fact that Rupert Murdoch's disreputable name is attached is only 1 of numerous red flags. Disappointing.
Title of Article: Long-term study reveals harm in regular cannabis use
Original Paper: Young-adult compared to adolescent onset of regular cannabis use: A 20-year prospective cohort study of later consequences
Lead Author Dr Gary Chan, excerpt from Bio: "Dr. Gary Chan is a NHMRC Emerging Leadership Fellow at the National Centre for Youth Substance Use Research. His principal research interest lies in the field of substance misuse prevention and the application of cutting-edge statistical method for longitudinal analysis and causal inference."
Methods: "A state-representative sample in Victoria, Australia (n = 1792) participated in a 10-wave longitudinal study and was followed from age 15 to 35 years. Exposure variable: Patterns of cannabis use across 20-years. Outcomes at age 35: Alcohol use, smoking, illicit drug use, relationship status, financial hardship, depression, anxiety and employment status."
Results: "Substantially more participants (13.6%) initiated regular use after high school (young-adult onset) than in adolescence (7.7%, adolescent onset). By the mid-30s, both young-adult and adolescent-onset regular users were more likely than minimal/non-users (63.5%) to have used other illicit drugs (odds ratio [OR] > 20.4), be a high-risk alcohol drinker (OR > 3.7), smoked daily (OR > 7.2) and less likely to be in relationships (OR < 0.4). As the prevalence of the young-adult-onset group was nearly double of the adolescent-onset group, it accounted for a higher proportion of adverse consequences than the adolescent-onset group"
Dr Chan says: "Overall, regular use of cannabis – more than weekly and especially daily use – was found to have harmful consequences, regardless of the age people began using it."
"The study was conducted in collaboration with Murdoch Children’s Research Institute and the University of Melbourne."
I quit smoking because I was getting gum infections all the time. It wasn't the only reason, just that last one that pushed me to quit. Inflamed gums don't feel so good.
I still have a recessed gum line around a tooth where I would hold the cigarette. I have to believe that hot smoke from a joint causes the same type of irritation to tissue.
[+] [-] oddlama|5 years ago|reply
> “Overall, regular use of cannabis [...] was found to have harmful consequences, regardless of the age people began using it.”
I am skeptical that this study is actually representative of the effects of cannabis, and does not instead depend on other, highly correlated effects, which are then presented as the reason. From my general (non-user) perspective, I would assume that there is probably a bias towards groups of people who have a higher chance to use substances in general, or live in a comparatively poor environment.
For example: Children of smokers often become smokers themselves (as numerous credible studies show). If they now start with cannabis, they would be included as the victims of cannabis in the discussed study. However, the causality is probably reversed here.
[+] [-] CameronNemo|5 years ago|reply
[+] [-] ehvatum|5 years ago|reply
In 20 years of various relationships, the only girlfriend who didn’t request that I quit smoking weed was extremely naughty and experimented with all kinds of substances, as she completed her residency at a children’s hospital. She married someone with more money, God help him.
So, it doesn’t surprise me that people not in a relationship tend to smoke more weed.
[+] [-] mpfundstein|5 years ago|reply
But then I've just finished reading the thread about scientific misconduct.... Not sure what to trust anymore
[+] [-] antiquark|5 years ago|reply
As always, remember that correlation is not causation.
For example, maybe people with depression or anxiety are using cannabis to self-medicate.
[+] [-] joe-collins|5 years ago|reply
So, mix in the confounding factor of it not being legal during those years.
[+] [-] saalweachter|5 years ago|reply
Consider if the data had fallen out the other way: if there was no correlation between these measures of harm and cannabis use, that would have been evidence of a lack of harm from cannabis use.
So even if you can't draw any strong conclusions from this study, it's still an interesting data point.
[+] [-] unknown|5 years ago|reply
[deleted]
[+] [-] unknown|5 years ago|reply
[deleted]
[+] [-] nickff|5 years ago|reply
[+] [-] username90|5 years ago|reply
https://www.drugabuse.gov/publications/research-reports/mari...
We wont know for sure until this bigger study is done, but if you care about your brain you probably should stop with cannabis until we know its safe:
https://www.drugabuse.gov/drug-topics/adolescent-brain/longi...
[+] [-] worik|5 years ago|reply
Around drugs there is no dispassionate reasoning these days.
[+] [-] whimsicalism|5 years ago|reply
[+] [-] 12bits|5 years ago|reply
Heading into my 40s with the plan to stop daily consumption, currently only have CBD strains in the house, my friend likes to the call it methadone for pot heads. Wish me luck.
The one person from our group of friends is schizophrenic and it was heavy cocaine use that seemed to have opened that pandoras box. He's many many years sober and steady eddy on his medication doing really well.
Another friend is bipolar schizoaffective and his relationship with cannabis is toxic at best. He knows it's the last thing he should be indulging in, but unfortunately in his mind he can't find any other way to fall asleep. Heavy indica strains tend to bring on mania for him.
[+] [-] zaroth|5 years ago|reply
I used to use indica to sleep, due to absurd levels of restless leg that only kick in as soon as I lie down. Then a physician friend recommended trazodone.
I really enjoyed being able to dream again. I hadn't quite noticed that I had basically entirely stopped dreaming when using pot. And mostly, I like being able to smoke purely recreationally and sporadically, not relying on it medicinally and regularly.
[+] [-] RickJWagner|5 years ago|reply
A couple of my friends have since died (caused by substance abuse). I truly believe human beings are best off with fewer recreational chemicals in their bodies.
[+] [-] abandonliberty|5 years ago|reply
Opened the box indeed. I wonder how many latent schizophrenics never experience symptoms thanks to never hitting a precipitating event, pharmaceutical or otherwise.
[+] [-] brdd|5 years ago|reply
[+] [-] worik|5 years ago|reply
Since then there have been hundreds of studies.
Generally cannabis, and recreational drugs generally, have not much in the way of negative measurable effects.
Remember it is only good drugs that have to be banned: There are no laws (generally) against Atrpine (datura), digitalis (foxglove) et. el. Just the good, fun, safe drugs have to have laws against them.
[+] [-] sjm|5 years ago|reply
What a joke. How many studies have been done on the negative effects of alcohol with no comment on the "importance for countries who have already legalised" recreational alcohol use?
[+] [-] NalNezumi|5 years ago|reply
>not be in a relationship at age 35
and it's light on any details or insight. It's a ridiculous hit piece with nothing but academic resume padding, but from none other than professors, that get amplified by shoddy journalism. Probably with some ulterior ideological motives (for funding maybe?)
Most of all: It's not tech related. Why is this voted up so much?
[+] [-] hombre_fatal|5 years ago|reply
Single high value people at age 35 describes most long term expats I meet at the beach who have very little in common with most of the population.
Btw look around, this isn’t just a tech forum that wants to debate JS and OO all day (just half of every day). It’s on the front page because we like talking about drugs. Though let me be the first to point out to you that drugs are a permanent passenger in the larger culture of tech.
[+] [-] tqi|5 years ago|reply
[1] https://news.ycombinator.com/item?id=25928310
[+] [-] abandonliberty|5 years ago|reply
Because I don't have poor mental health, I don't use social media or cannabis.
Poor mental health predisposes you for social media use. Would someone with good mental health really get deeply involved with those platforms? :)
[+] [-] devlopr|5 years ago|reply
Other headlines they could have used.
Being a relationship doesn't affect your depression / hard drug use / etc
Austrialians start using weed much later in life
[+] [-] julienb_sea|5 years ago|reply
I've found when I am in a daily usage phase, I am overall more lethargic, less motivated at work, less motivated at fitness, and less motivated to go on dates. These problems don't entirely clear up when I am outside of a daily usage phase, but progress made in those areas tends to erode. This doesn't dramatically affect my life, I am certainly functional and overall productive at work and in my social life, but at the same time the findings make sense to me.
[+] [-] Hydraulix989|5 years ago|reply
"By the mid‐30s, both young‐adult and adolescent‐onset regular users were more likely than minimal/non‐users (63.5%) to have used other illicit drugs (odds ratio [OR] > 20.4), be a high‐risk alcohol drinker (OR > 3.7), smoked daily (OR > 7.2) and less likely to be in relationships (OR < 0.4)."
So this study basically shows that cannabis users are more likely to experiment with other drugs -- meanwhile, the "less likely to be in relationships" factor might not even be statistically significant (the OR is < 0.4). I'm not sure how one defines "anti-social behaviours" either, other than conforming into some societal box.
[+] [-] unknown|5 years ago|reply
[deleted]
[+] [-] ttt0|5 years ago|reply
I didn't even need a study to know that. Why people are so in denial about cannabis?
[+] [-] lmilcin|5 years ago|reply
Maybe having paid job makes you use weed less (for possible consequences of being high at work)?
Maybe cannabis doesn't cause depression but rather it is just correlated for some other unknown reason?
That's again, very poorly written article by a confused author who does not understand causality and correlation.
[+] [-] coinward|5 years ago|reply
[+] [-] Clewza313|5 years ago|reply
https://en.wikipedia.org/wiki/Queensland_Police_Service#Crit...
[+] [-] betenoire|5 years ago|reply
[+] [-] julienb_sea|5 years ago|reply
Well this is really a stab to the heart
[+] [-] httpz|5 years ago|reply
If you showed this article to a Dutch person, they'll probably just say "duh.." then continue smoking their weed instead of tearing apart this article like a lot of people here.
[+] [-] Joking_Phantom|5 years ago|reply
Based on their alarmist and projective tone, they probably made this error on purpose in order to push an agenda for their own benefit. The fact that Rupert Murdoch's disreputable name is attached is only 1 of numerous red flags. Disappointing.
Title of Article: Long-term study reveals harm in regular cannabis use
Original Paper: Young-adult compared to adolescent onset of regular cannabis use: A 20-year prospective cohort study of later consequences
Lead Author Dr Gary Chan, excerpt from Bio: "Dr. Gary Chan is a NHMRC Emerging Leadership Fellow at the National Centre for Youth Substance Use Research. His principal research interest lies in the field of substance misuse prevention and the application of cutting-edge statistical method for longitudinal analysis and causal inference."
Methods: "A state-representative sample in Victoria, Australia (n = 1792) participated in a 10-wave longitudinal study and was followed from age 15 to 35 years. Exposure variable: Patterns of cannabis use across 20-years. Outcomes at age 35: Alcohol use, smoking, illicit drug use, relationship status, financial hardship, depression, anxiety and employment status."
Results: "Substantially more participants (13.6%) initiated regular use after high school (young-adult onset) than in adolescence (7.7%, adolescent onset). By the mid-30s, both young-adult and adolescent-onset regular users were more likely than minimal/non-users (63.5%) to have used other illicit drugs (odds ratio [OR] > 20.4), be a high-risk alcohol drinker (OR > 3.7), smoked daily (OR > 7.2) and less likely to be in relationships (OR < 0.4). As the prevalence of the young-adult-onset group was nearly double of the adolescent-onset group, it accounted for a higher proportion of adverse consequences than the adolescent-onset group"
Dr Chan says: "Overall, regular use of cannabis – more than weekly and especially daily use – was found to have harmful consequences, regardless of the age people began using it."
"The study was conducted in collaboration with Murdoch Children’s Research Institute and the University of Melbourne."
[+] [-] eigenrick|5 years ago|reply
Correlation.
Population bias.
Correlation.
Slow day in the academic universe?
[+] [-] TedDoesntTalk|5 years ago|reply
[+] [-] skierguy|5 years ago|reply
[+] [-] dukeofdoom|5 years ago|reply
I still have a recessed gum line around a tooth where I would hold the cigarette. I have to believe that hot smoke from a joint causes the same type of irritation to tissue.
[+] [-] snypher|5 years ago|reply
Get back to me with some real science, please.
[+] [-] rarefied_tomato|5 years ago|reply
- smoke alone instead of meeting up with friends
- be less productive/successful
- smoke as an aid for emotional pain
[+] [-] ta988|5 years ago|reply
[+] [-] unknown|5 years ago|reply
[deleted]