The actual results are less scary: long-term, heavy cannabis use that begins in adolescence correlates with increased rates of psychological conditions and IQ decline.
Edit: To inject a personal anecdote: every time I travel to Europe, I see people my age (and sometimes substantially younger) drinking beer and smoking marijuana. I almost never see reckless drinking or smoking the way I do in the US (e.g., at every college event), and I attribute that to a cultural failure of ours.
My opinion: if we want to stop the kinds of results that these studies show, then we should focus our efforts on reducing the taboos/absence of cultural knowledge that lead to binge usage.
Once a week is not "binge usage." That term isn't used anywhere in the study. The study doesn't make or support the claim that only binge usage causes mental decline.
What the study supports is that weekly long-term use beginning in adolescence causes permanent mental decline.
Furthermore the NYT links many other studies to support their position, and a recurring theme is that we still don't understand all the long-term effects of marijuana.
I have a feeling that if this article was about tobacco or alcohol the comments would look totally different. I like cannabis, I think it's probably more benign than both of those drugs, but I don't think we should give it a free pass because of its counterculture association or any other reason. By the admission of researchers it is not well understood, so there is a good case to be made that the path of least harm is to legalize carefully and in stages.
It's fine if this is actually tested in an RCT instead of a silly correlation that has any number of confounders such as:
- parental care - stable young people start smoking later and smoke less and/or less often
- wealth - rich people -"-
- mental illness
- social groups where early marijuana use can be special in other ways
- other concurrent habits
I'd like to at least see a thorough analysis instead of one potentially random number average need with all sorts of biases. And just the bare bones of statistics have been applied to insufficient data.
The most reasonable paper, the IQ one, is funded by a drug prevention and treatment center.
And the other linked papers are a big bag of laughs. FMRI "looking" abnormal? Bah. Epigenetic study in vitro, wow, very useful if you're made of glass.
Precautionary principle is well applied here already, and in more reasonable countries. Remove reasons for abuse and it rarely happens.
Perhaps you're okay with taking something that makes you even the slightest bit dumber, but I am not. Importantly? Do you think kids should be allowed to make this mistake when they don't understand this difference?
Does banning it actually decrease usage (I'm genuinely asking, as it's a highly political issue and I can find articles claiming either side)? Also I feel it's much more our duty to inform people as much as possible to empower them to make the best decisions (for the same reasons I think a lot of anti-drug campaigns that exaggerate the dangers of drugs do more harm than good, or why abstinence only sex ed is a net negative). Kids are going to do stupid shit, it's an invaluable part of growing up. If they're not directly harming anyone else, it should ultimately be their choice - even if we think it's a bad one. What makes an arbitrary age any better?
My argument does not have much data behind it, and I welcome studies that contradict my stance.
So, this is true. But it's also lacking context: that same table also shows a nearly identical gain for adolescents who didn't smoke marijuana at all, suggesting that the negative results for the "used, never regularly" cohort are within the margin of error.
Also consider the scale: the authors say that -0.38SD corresponds to a decline of ~6 IQ points; that means that usage cohorts 1, 2, and 3 each declined by less than 3 points. I'd have to do more background reading, but I suspect that creeps into confidence interval territory. Similarly, we are left without a good explanation for the relatively smaller decline in IQ for the 2 waves cohort. By and large, not confidence inspiring.
> Perhaps you're okay with taking something that makes you even the slightest bit dumber, but I am not.
I'm not okay with taking things that'll make me dumber. However, I'm not convinced that marijuana usage, on par with* reasonable alcohol consumption, would make me dumber. Beyond that, I am confident that several other environmental factors are far more important: absence of lead paint, proper early-life nutrition, &c.
> Do you think kids should be allowed to make this mistake when they don't understand this difference?
I take issue with framing it as a mistake. Per my anecdote, I think that adolescents harm themselves more in a culture that treats alcohol and marijuana as taboos. We should definitely put effort towards stopping adolescent addiction; I think our efforts there will benefit greatly from a culture shift.
* Edit: "on par with" meaning "suitably scaled," not "one joint per beer" or something silly like that.
If we are in personal anecdotes, there is an disproportionately high rate of people around me with light to severe psychological conditions that started marijuana around or before 15 (at least 4 are/were close).
If you want to say that cognitive development isn't done until 25, and so people can't be considered adults until then, you'd better be ready to argue that for a whole lot of other sacred cows.
They aren't the only one, and they probably did what they did by doing a blunt approximation of what the auto insurance industry came up with regarding age.
You said that is not true in Tennessee and, as I explained, you are wrong about that. While I'm sure you knew what you meant, given your lack of explanation it is assumed you were directly replying to the central tenet of the previous comment (i.e. that persons under 25 are less adulty and should be treated as such).
I don’t see setting the marijuana age limit to be 25 to be any more/less arbitrary. No need to bring sacred cows into this.
Even at the height of the drug war, when cannabis was illegal in every state in the US, it was incredibly easy to get for anyone who wanted it.
Now that it's effectively legal in many states, it's even easier to get. People below whatever minimum age limit might not be able to legally get in to a business that sells cannabis, but already plenty of underage drinkers get in to bars with fake ID's, and they could always get the cannabis from their friends, black/gray-market dealers, or just grow their own from seed.
The Netherlands, where cannabis has been effectively legal for many decades, has a much lower percentage of youth who use cannabis than the US. It's just not considered cool there, as it's not forbidden as it is in the States. Often, the attitude among natives in general there is that it's something that mostly tourists or foreigners do. But in the US, forbidden fruit is going to look twice as attractive and taste twice as sweet.
So setting a minimum age limit might have the paradoxical effect of making users out of more youth than would otherwise try it.
History says again and again that banning something doesn't make it happen less, it just lets criminal elements profit from it.
'Courtwright’s The Age of Addiction has the statistics: “Per capita consumption initially fell to 30 percent of pre-Prohibition levels, before gradually increasing to 60 or 70 percent by 1933.” That suggests a 30 percent reduction, at a minimum, in consumption — although that was less than the initial effect, as people figured some ways around the law.'
Even if Prohibition itself was responsible for the reduction in drinking, we must consider whether the overall effect on society was worth it. This effect included an enormous increase in organized crime, murders and other types of violence, and widespread corruption. American society as a whole decided that no, it was not worth it, and repealed Prohibition.
The effect of the current war on drugs is arguably much, much worse than Prohibition ever was.
I’m just saying that some state setting marijuana age limit at 25 isn’t going to make people question drinking age, voting age, military age, etc.
For alcohol, neurological effects can be observed in those who consume as little as 21 drinks per week (https://www.ncbi.nlm.nih.gov/pubmed/9500305). Your brain is just a bunch of electrically powered neurons swimming in a chemical bath - it's surprising how little of a substance over a regular time period can have an effect.
That is an incredible amount of alcohol as a minimum. Was that a typo, or does it really take that much to see significant negative effects?
Yes and even drinking that quantity of high ABV beer or large glasses of wine that you describe and you'd still have to do it every day of the week to hit 21 drinks a week.
It is, as suggested upthread, an incredible amount of alcohol to describe with “as little as”.
This is not typical of a normal working adult. I don't care what social circles you're a part of, unless it's some weird Instagram socialite promoting alcoholic beverages.
I'm sure there are social circles where eating 5000 calories a day is considered normal too. Doesn't mean we should normalize it or pretend it's healthy.
Many cocktails could easily be 3 or 4 "drinks".
Which still isn't saying 21 "standard" drinks a week isn't a fair amount, but it's not that crazy.
For instance, say you go out on a Friday and have 5 pints of an 8% IPA over the course of the evening.
That's 10.4 standard drinks.
While looking back I can see it wasn’t healthy... nachos and a couple beer on Tuesday night after our long engineering lab, and 3 or 4 mini-pitchers (3oz) at the bar on Friday and Saturday night pretty quickly adds up to, say, 27 drinks in a week. I was perfectly functional (minus Saturday and Sunday mornings where I’d sleep in until 11 or noon), passed all my classes, even made the Dean’s list.
Definitely not recommended, but not unheard of. I have a much healthier relationship with booze now, and I’d be broke if I drank that much of the good stuff :)
21+ drinks per week is 2 nights out for some people.
Because it is a lot.
> While it's 21 more than I have a week these days, I've gone stretches in my younger years with several beers a night. Easily drinking 21 a week.
So...you used to drink a lot. What's your point?
> 21+ drinks per week is 2 nights out for some people.
Yes, some people are very heavy drinkers. Again, what's your point?
That in my experience, for youngsters, 21 drinks a week isn’t a lot.
> Again, what’s your point?
Please see above.
I’d wager a significant (20% or so) portion of youth (< 25) drink 21+ per week semi regularly.
That’s relevant to the comment I was replying to, and the studies it references.
Now that I’ve clarified things, what is your point?
* How stimulating their environment is,
* Disease (although this is generally towards the negative).
All of these can be influenced by behavior- people's eating habits affect their nutrition, and people who seek out intellectual stimulation are more likely to find it than those who don't.
Do you have any sources for that bold claim?
I don't write that to dispute the point of the article. However, many findings do dispute the age of adulthood.
It includes things like Wernicke-Korsakoff syndrome (also called Korsakoff's Phychosis), and alcohol-related dementia.
It's likely that younger people are more susceptible to alcohol related harm.
People who drink heavily are at higher risk.
This would be people who drink more than about 50 units a week for men, or 35 units per week for women. (Current safe drinking guidance is to drink no more than 14 units a week, spread out, with some days drink free).
There are roughly 40 units in a litre bottle of spirits.
18 UK pints of 5% ABV beer would be 50 units. Over a week that might be 2 pints a day and a big session on friday and saturday.
It's hard to know how many people drink this heavily because the stats are all self reported, people don't know what a unit is nor how strong the alcohol they drink is, and alcohol affects memory so people can't remember what they've drunk or when. But we think about 4% of men and 3% of women drink this much. https://www.drinkaware.co.uk/research/data/consumption-uk/
Alcohol is not what is being discussed.
Of course putting something in my brain that never belonged in the first place would likely be bad for my brain judging from common sense. However, thanks to the fact that I've been enjoying getting high for years and due to the fact I don't want to admit I've been damaging my brain I'm going to google search very specific results that support my bias.
The above link is a more convenient scientific result to believe so despite offering nothing more then the NYtimes article (just correlation and experimental evidence) I'm going to choose what I like to believe and this harvard study is it.
Logical conclusion: Marijuana increases IQ. Also I'm high right now, which makes my judgement more precise because my IQ is higher at this very moment.
That said intuitively that weed makes you stupid and crazy doesn't surprise me in the slightest. Unfortunately smoking weed is the most fun before things get serious with work and family in late 20s.
Another thing that came to mind, in the creativity enhanced altered state I'm currently in and have been in since age 12, is the exact mechanism is still up for debate regardless of established causality. I'm hoping the IQ decline comes from sitting stoned playing video games over engagement in school and work, as opposed to THC itself directly causing neurological learning deficits that are not reversible
In other words, is there a liability issue?
Any lawyers care to chime in?
Alcohol can kill you, both from ingesting too much and from quitting after heavy usage. Cannabis does neither, and that's not even close to "roughly."
There are smokeless consumption alternatives, which anyone mindful of their lung health should choose instead.
No one is saying smoke doesn't cause lung cancer. What is being said is that cannabis consumption will not kill you via overdose.
For any substance that is consumed repeatedly, it is useful to "binary search" for the minimum effective dose. This tends to cancel out potency as a variable, while reducing the effects of tolerance.
IQ tests are too narrow to assess the real picture. Can't believe these are still in use. And what I think researchers should really test
is level of "will power" i.e. self-control.
Once a week is indeed too frequent. You have to take longer breaks. If used recreationally at least 3 weeks between single uses, and once, or better twice, a year a 6-8 weeks break. Plus, never smoke it, only eat. Smoking is the most addictive way of administration.
Also, the title is misleading indeed. What marijuana does is sort of "conserving" your brain, not damaging it. It's absolutely the opposite. It's like neural back pressure.
I share the same opinion as others in this thread that say there is a certain age where you should be considered an adult and therefore old enough to determine whether or not you should do something that is bad for you.
I’d be interested in seeing studies about marijuana’s impact on the brain’s creative abilities to contrast with this.
Because the devil’s advocate in me thinks “We have enough high IQ people in this world and not enough high creativity people.”
There certainly is an abundance of anecdotal evidence that marijuana boosts creativity from artists and musicians.
Not brain damage per se:
> Caffeine can have negative effects on anxiety disorders. According to a 2011 literature review, caffeine use is positively associated with anxiety and panic disorders. At high doses, typically greater than 300 mg, caffeine can both cause and worsen anxiety.
> Caffeine-induced anxiety disorder is a subclass of the DSM-5 diagnosis of substance/medication-induced anxiety disorder.
However I will note that it does list a bunch of positive effects of caffeine use; including reduced risk of depression ("although conflicting results have been reported").
I am pretty sure there is a positive correlation between musical intelligence and marijuana.
While we are on the topic of addiction let's stop blaming phones and blame mirrors first.
I'm pretty sure you don't understand the difference between long and short term usage.
Try drinking 40 cups of coffee a day and not sleeping for four nights. That's detrimental for your brain too.
That's just... like, your opinion, man.
* This unbiased message brought to you by big Pharm and America's alcohol brewers.
Are we going to risk the lives of our children based upon a thesis which might or might not be correct?
All I know, is that my cousin got high once and you know, he started eating like really weird foods. And then he just felt like he didn't belong anywhere. You know kinda like "Twilight Zone".
Marijuana advocates should prepare themselves to take moral responsibility for the many significant negative consequences of increasing use, including increased schizophrenia rates, traffic fatalities, industrial accidents along with overall lower worker productivity.
The “but compared to alcohol” is a shallow argument used by these biased advocates selfishly looking for approval for their own recreational vice.
I don't see you calling for any moral responsibility there.
Sorry, the science just isn't that good on this subject.
> selfishly looking for approval for their own recreational vice
I'd say destroying the black market and keeping convictions off people's records is a total win, even in the eyes of the rest of us that don't smoke weed.
> I personally doubt that we will see increased schizophrenia rates from legal weed. We may not see any of the other harms you list, either. Sorry, the science just isn't that good on this subject.
What makes you doubt it? Why would it be more likely it is harmless than harmful? Even if I had no prior scientific data but tried to guess if regular use of a mind altering substance would be harmless or harmful, wouldn’t the prior lean towards harmful?
You might want to check recent data out of Colorado. It isn’t looking good.
> I'd say destroying the black market and keeping convictions off people's records is a total win, even in the eyes of the rest of us that don't smoke weed.
How do you know it is a win if we don’t know the unsettled science yet? Might be a pretty big gamble.
One of the biggest obvious problems with legalized Marijuana that they are struggling with in Colorado is the simple concept of having a test to determine if an individual is under the influence. Such a test would be a breakthrough in resolving some of the more serious immediate risks and enable enforcement of common sense rules.
Do you want your nurse at the ER impaired from Marijuana? Your bus driver? The construction crane operator?
I argue the legalization advocates are being irresponsible without “settled science” and without an ability to measure or detect use.
Do you want your nurse at the ER impaired from coffeebean junk? Your bus driver? The construction crane operator?
I’d like to see legal age of use go up to 26. It seems like a good balance. Legalize, yes, but you have to be mature about it.
It’s time to realize that 16 to 25 you are still pretty immature.
Then I thought 25 was a good age of majority, but as I got older I realised even 30-year-olds can act pretty immature.
Now I think 35 is a good age of majority... but then again even some of my peers can make some pretty poor decisions, so maybe 45?
Or we could just admit that this is what mature humans look like. We're still making dumb decisions and still learning from them, right up til we die.
Sincerely, a 25 year old who voted so he can legally smoke weed in Canada.
Edit (since you edited your number down from 30): And vote.
All systems lead to abuse, including the existing system that artificially selects one age for a variety of rights/obligations with the notable exception being alcohol consumption. The rational approach would be to find a system that creates the minimal level of abuse. If that's the current system then so be it, but an effort should be made.
Edit: it's a binary system. You either are or are not.
Do not cite cigarette purchase age limits as the cause of their decline. A combination of price and social rejection of cigs as disgusting has caused the decline in cigarette usage among youth.