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Marijuana Damages Young Brains

119 points| pseudolus | 6 years ago |nytimes.com | reply

116 comments

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[+] woodruffw|6 years ago|reply
Scary title.

The actual results[1] 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.

[1]: https://www.pnas.org/content/pnas/early/2012/08/22/120682010...

[+] apatters|6 years ago|reply
I think you're making it sound less scary than it actually is. The study you linked looked at adolescents who used cannabis once a week, and found that they suffered a permanent decline in IQ.

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.

[+] ramraj07|6 years ago|reply
Thanks for the citation, but not sure how that's less scary. Sure they see the most effect statistically in long-term heavy users, but there's no evidence to indicate that such amount of usage is the threshold. Even occasional users show a slight negative Delta IQ in the tables.

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?

[+] tarsinge|6 years ago|reply
> 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.

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).

[+] danielscrubs|6 years ago|reply
North Europeans don’t smoke marijuana. It’s both very illegal and is seen as trashy. Heavy drinking on the other hand is popular.
[+] stormbrew|6 years ago|reply
The legal age isn't set where it is because that's the age at which marijuana is deemed to have no negative effects, any more than it is for alcohol or any other substance that can be habit forming. It's just the age at which people are considered responsible enough to make a decision on their own about the risks and benefits involved.

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.

[+] ramraj07|6 years ago|reply
Which makes sense too in many ways. The only people who've had to bet their money on making a decision on what age to consider people as adults at, is the rental car industry. Incidentally they came up with the 25 number too, I guess purely actuarially.
[+] paulcole|6 years ago|reply
Voting age and drinking age have been separated for decades and we’ve gotten used to it.

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.

[+] Donald|6 years ago|reply
Note that ethanol, and a host of other mind-altering substances, should also be avoided until neurobiological adulthood (approximately 26): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4669962/

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.

[+] shadowoflight|6 years ago|reply
> as little as 21 drinks per week

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?

[+] whycombagator|6 years ago|reply
A lot of people are saying 21 drinks a week 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.

21+ drinks per week is 2 nights out for some people.

[+] loser777|6 years ago|reply
What is the role of THC here? Presumably THC will change your behavior, and if your behavior over a long period of time impacts IQ or any of the metrics mentioned (e.g., "executive function, processing speed, memory, attention span and concentration...") then it is difficult to say that THC is the direct cause of "damage." When we say that being poor lowers your IQ or decision making capabilities, most infer that this is the result of secondary effects like stress and anxiety rather than your actual wealth alone. Is the message that THC causes damage like cigarette smoking, or like being poor---or both?
[+] quotemstr|6 years ago|reply
IQ is mostly invariant of behavior, and absent gross brain injury, is largely fixed over one's lifetime.
[+] eMSF|6 years ago|reply
Alcohol damages brains of all ages, as well.

I don't write that to dispute the point of the article. However, many findings do dispute the age of adulthood.

[+] ramraj07|6 years ago|reply
Does alcohol induce long-term damage on the brain in proper adults?
[+] threeseed|6 years ago|reply
Of course you wrote that to dispute the point of the article.

Alcohol is not what is being discussed.

[+] crimsonalucard|6 years ago|reply
I smoke this stuff everyday since I was 16 so I'm biased. Basically I need more than experimental evidence or correlations to believe the results as this completely invalidates my past behavior. Don't expect me to flip my opinion over night based on logic. Humans aren't logical creatures. If I changed my opinion then I'm basically admitting to taking drugs to make my brain stupider since I was a kid.

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.

See here: https://www.inc.com/cynthia-than/the-surprising-way-to-be-be...

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.

[+] spacedog11|6 years ago|reply
I wonder if the I.Q decline is caused by the use of Marijuana or if it's caused by the life style of Marijuana users?
[+] smokedatchichi|6 years ago|reply
Being a heavy stoner through 25 is highly correlated with at least alcohol consumption, pre-existing mental health problems, and polysubstance abuse.

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

[+] tootahe45|6 years ago|reply
I don't remember the 'smartest' people turning up to school with cans of energy drink, going to parties, being obese, smoking every day and bragging about it, so that has always been my conclusion. I don't consider myself one of the smart ones, before anyone downvotes, I've had my own issues with addictive/compulsive behaviors which certainly took a toll on my academic & social performance in HS.
[+] lanrh1836|6 years ago|reply
Ive only rarely had a good experience with weed and ironically have not had any since it was made recreationally available in CA. It usually just makes me feel sick or very paranoid. Probably best for my wallet.
[+] tachyonbeam|6 years ago|reply
I'm in the same boat. It makes me unbearably anxious and will ruin any evening out. I've tried multiple kinds, and even the varieties richer in CBD cause me anxiety. It's just not a substance I can enjoy.
[+] dade_|6 years ago|reply
Right now Marijuana destroys your life in the US if you get caught with it. So worry about decriminalization/legalization and then worry about why poor Timmy isn't very swift. Cigarettes and alcohol damage most organs in the body, so educate people as best you can, but people a lot younger than 18 are going to use pot no matter what age it is legalized for so I am not sure what good this policy advice is from NYT.
[+] Bud|6 years ago|reply
This isn't actually advice from the NY Times. It's an editorial. As such, it represents the views only of the two writers involved.
[+] jweir|6 years ago|reply
If you sell a product, with known harmful effects, and you do not warn the buyer, are you not liable?

In other words, is there a liability issue?

Any lawyers care to chime in?

[+] baroffoos|6 years ago|reply
It seems to me that it poses roughly the same risk as alcohol. I wonder if legalization changes the amount of children with access to the drug. If all sales are illegal then someone selling it probably won't care if they are selling to an adult or a 15 year old but if selling to an adult is legal but selling to a child is not the risk is probably not worth it.
[+] Slothrop99|6 years ago|reply
Agreed. When I was a teenager, everyone knew it was easier to buy marijuana than any sort of liquor, because there was basically no underground market for the latter. All the knee-jerk stoners in here spamming the same point are probably oblivious that regulated sales and minimum age is actually somewhat effective.
[+] rhizome|6 years ago|reply
>It seems to me that it poses roughly the same risk as alcohol

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."

[+] SubiculumCode|6 years ago|reply
Not nearly the same risk. But not safe for developing minds, for sure.
[+] p1mrx|6 years ago|reply
> The risk that marijuana use poses to adolescents today is far greater than it was 20 or 30 years ago, because the marijuana grown now is much more potent.

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.

[+] astazangasta|6 years ago|reply
The potency stuff is such garbage. So before people smoked an entire joint to get as stoned as they now get off a few hits. So what? People titrate their intake. Whenever i see this line i just stop reading because i feel the author is not interested on honest argumentation.
[+] timka|6 years ago|reply
TL; DR. Only oral administration. At least 3 weeks between uses.

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.

[+] amanzi|6 years ago|reply
This debate is just starting in NZ where we will be voting next year in a referendum on legalising personal use of cannabis. The draft legislation has set the legal age to be 20, though this has drawn criticism from those that say the age should be 25 based on the same arguments put forward in the linked article.

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.

[+] pythonwutang|6 years ago|reply
This focuses on IQ and memory but doesn’t it also impact creativity?

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.”

[+] nilolo|6 years ago|reply
I would be interested in this as well, but how do you measure creativity? Data on long-term effects of marijuana is rare to come by and that's when we are looking at a clear metric like IQ.
[+] all_blue_chucks|6 years ago|reply
Are all drugs tested to see if they affect IQ tests over extended periods?
[+] m0llusk|6 years ago|reply
Drinking too much water also damages young brains. Maybe we should restrict access to water also.
[+] sirusdas|6 years ago|reply
See it's what you do after taking it! Marijuana will just help you with it! Just like you eat lot of junk food and sit at one place every day that's not going to make you fit and you can't blame the food it's you! If you learn to focus after taking marijuana it's the best thing and if you try to distract it's the worst thing too!
[+] foolfoolz|6 years ago|reply
also damages young brains: binge watching, caffeine, social media, bullying, sleep deprivation...
[+] glerk|6 years ago|reply
Got a source for caffeine damaging the brain?