Cannabis smoking 'permanently lowers IQ'

Teenagers who regularly smoke cannabis are putting themselves at risk of permanently damaging their intelligence, according to a landmark study.

Researchers found persistent users of the drug, who started smoking it at school, had lower IQ scores as adults. They were also significantly more likely to have attention and memory problems in later life, than their peers who abstained. Furthermore, those who started as teenagers and used it heavily, but quit as adults, did not regain their full mental powers, found academics at King’s College London and Duke University in the US.

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Taylor said:

Full story is here

"Persistent users" of marijuana - those that consistently use four or more times per week - show a fairly significant cognitive deficit later in life. The apparent damage is irreversible if heavy use begins in adolesence. Those who began heavy use in college and did not use for at least a year prior to testing showed no deficit.

This is yet another study challenging the presumption that cannibis is a relatively innocuous drug. This mistaken belief is actually becoming more prevalent among people in the US - especially the young. The article notes that this is the first year that US high school students are more likely to use marijuana than tobacco.

The study suffers from many of the typical limitations associated with this sort of research. Although they found evidence of a relationship between early cannibis use and IQ, we don't know what the actual cause of the decline is. Some may ask "does cannibis use lead to lower IQ or does lower IQ lead to cannibis use?" - but given the pattern of results, it seems more likely that the cause is cannibis use or another factor associated with cannibis use (especially given that they looked at just one cohort).

Regardless, it's likely that the study will be welcomed by those who question the use of cannibis -- and discounted by those who defend it (especially among those that used heavily in adolescence ).

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lpast said:

Study after study shows marijuana to be a detriment to health and well being and they all get buried because all the heads out there want their weed.

Ill mention just one here...Marihuana smoke is more of a carcinoginen that cigarette smoke...yet there are people that rant to ban cigarette smoking and want weed legalized.

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Wake said:

Would you show that marijuana smoke is more of a carcinogen than nicotine?

No one has ever died from smoking marijuana iirc. On the other hand, many, many people have developed problems and dies from inhaling poisonous cigarette smoke.

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lpast said:

Effects on the Lungs

Numerous studies have shown marijuana smoke to contain carcinogens and to be an irritant to the lungs. In fact, marijuana smoke contains 50-70 percent more carcinogenic hydrocarbons than tobacco smoke. Marijuana users usually inhale more deeply and hold their breath longer than tobacco smokers do, which further increase the lungs' exposure to carcinogenic smoke. Marijuana smokers show dysregulated growth of epithelial cells in their lung tissue, which could lead to cancer;6 however, a recent case-controlled study found no positive associations between marijuana use and lung, upper respiratory, or upper digestive tract cancers.7 Thus, the link between marijuana smoking and these cancers remains unsubstantiated at this time.

Marijuana | DrugFacts | National Institute on Drug Abuse


Just do a quick google wake you will find more

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lpast said:

Effects on the Lungs

Numerous studies have shown marijuana smoke to contain carcinogens and to be an irritant to the lungs. In fact, marijuana smoke contains 50-70 percent more carcinogenic hydrocarbons than tobacco smoke. Marijuana users usually inhale more deeply and hold their breath longer than tobacco smokers do, which further increase the lungs' exposure to carcinogenic smoke. Marijuana smokers show dysregulated growth of epithelial cells in their lung tissue, which could lead to cancer;6 however, a recent case-controlled study found no positive associations between marijuana use and lung, upper respiratory, or upper digestive tract cancers.7 Thus, the link between marijuana smoking and these cancers remains unsubstantiated at this time.

Marijuana | DrugFacts | National Institute on Drug Abuse


Just do a quick google wake you will find more

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Hatuey said:

Okay, so I say we should ban rum (40% alcohol) and simply legalize wines under 25%? Does that sound logical to you?

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Wake said:

...I've used that same link before when I was convinced marijuana was as bad as nicotine. Then, a later 2012 government study was released, showing it was relatively harmless, iirc.

Yep, that's the exact link I used to use.

Cigarette smoke is far more dangerous, with cyanide, various other poisons, etc.

There's no argument that marijuana does have some sort of carcinogenic effect, but on par or more than cigarette smoke? That cannot be. You do not see millions suffering and dying because of inhaling marijuana smoke.

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lpast said:

Ok..weed is good for you...and all the studies are wrong and your one study is right...I CONCEDE wake...I dont have to worry bout it cuz I dont smoke weed Ill let you worry about it.

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Wake said:

Lpast...

...I didn't argue that weed was good for you, or that it was neutral.

It's carcinogenic and damages brain cells.



That said, it's not deadlier than cigarette smoke.

Marijuana hasn't killed millions of people.

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lpast said:

Effects on the Lungs

Numerous studies have shown marijuana smoke to contain carcinogens and to be an irritant to the lungs. In fact, marijuana smoke contains 50-70 percent more carcinogenic hydrocarbons than tobacco smoke. Marijuana users usually inhale more deeply and hold their breath longer than tobacco smokers do, which further increase the lungs' exposure to carcinogenic smoke. Marijuana smokers show dysregulated growth of epithelial cells in their lung tissue, which could lead to cancer;6 however, a recent case-controlled study found no positive associations between marijuana use and lung, upper respiratory, or upper digestive tract cancers.7 Thus, the link between marijuana smoking and these cancers remains unsubstantiated at this time.

Marijuana | DrugFacts | National Institute on Drug Abuse


Just do a quick google wake you will find more

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The findings echo results in some smaller studies that showed while marijuana contains some of the same toxic chemicals as tobacco, it does not carry the same risks for lung disease

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lpast said:

I believe it does and how could it not wake...did you read the study...do weed smokers inhale deeper and hold it longer ? yes...for gods sake wake..candle smoke is a known carcinogenin....dont try to tell me suckin on weed smoke isnt....but theres no sense arguing this point because weed lovers will get shrill and sarcastic over their weed...

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Taylor said:

Full story is here

"Persistent users" of marijuana - those that consistently use four or more times per week - show a fairly significant cognitive deficit later in life. The apparent damage is irreversible if heavy use begins in adolesence. Those who began heavy use in college and did not use for at least a year prior to testing showed no deficit.

This is yet another study challenging the presumption that cannibis is a relatively innocuous drug. This mistaken belief is actually becoming more prevalent among people in the US - especially the young. The article notes that this is the first year that US high school students are more likely to use marijuana than tobacco.

The study suffers from many of the typical limitations associated with this sort of research. Although they found evidence of a relationship between early cannibis use and IQ, we don't know what the actual cause of the decline is. Some may ask "does cannibis use lead to lower IQ or does lower IQ lead to cannibis use?" - but given the pattern of results, it seems more likely that the cause is cannibis use or another factor associated with cannibis use (especially given that they looked at just one cohort).

Regardless, it's likely that the study will be welcomed by those who question the use of cannibis -- and discounted by those who defend it (especially among those that used heavily in adolescence ).

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lpast said:

This isnt about alchohol this is about WEED

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lpast said:

Listen GUYS im not getting into another long drawn out weed thing...its what it is...and people believe what they want with weed....its just like alchoholics dont think their liver is going to die until their belly blows up....If you want to believe suckin on weed smoke wont hurt you....then who am I to tell you different carry on

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lpast said:

I believe it does and how could it not wake...did you read the study...do weed smokers inhale deeper and hold it longer ? yes...for gods sake wake..candle smoke is a known carcinogenin....dont try to tell me suckin on weed smoke isnt....but theres no sense arguing this point because weed lovers will get shrill and sarcastic over their weed...

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justabubba said:

that was my initial thought, too after reading about the dunedin study
but upon reflection i realized that it might have the effect of strengthening the justification to treat cannabis like alcohol, where its distribution can be better controlled and monitored. in that way, it would serve to diminish the opportunity for those under 18 (or 21) to gain access to something which is found to decrease one's projected IQ if abused during youth

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justabubba said:

thank you for that permission
but i have been doing so daily for the last 42 years

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lpast said:

My points been made

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