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What Happens When You Get Stoned Every Single Day For Five Years?

By 5-HT2A, Feb 3, 2016 | | |
  1. 5-HT2A
    New research published today in the journal JAMA Internal Medicine confirms what many of us have suspected for some time: If you smoke a lot of weed — like a lot of it — it can potentially do permanent damage to your short-term memory.

    Professor Reto Auer of the University of Lausanne led a team of researchers who examined data on the marijuana habits of nearly 3,400 Americans over a 25-year period. At the end of the study period, the subjects took a battery of tests designed to assess cognitive abilities — memory, focus, ability to make quick decisions, etc.

    The study found that people who smoked marijuana on a daily basis for a long period of time — five years or more — had poorer verbal memory in middle age than people who didn't smoke, or who smoked less. This association remained even after researchers controlled for a variety of other factors known to affect cognitive performance, including age, education, use of other substances and depression.

    Auer and his team measured lifetime marijuana exposure in a fantastic new unit of measurement they call "marijuana-years." Essentially, if you smoke pot every day for a year, that equals one marijuana-year of use. Ditto if you smoke every other day for two years, or once a week for seven years.

    [Scientists have found that smoking weed does not make you stupid after all]

    The relationship between marijuana exposure and memory problems was essentially linear. The more pot people smoked, the worse they performed on the memory tests. But just how much worse?

    Let's say we have two groups of 10 people each. You tell each of them a list of 15 words and ask them to memorize them. Then 25 minutes later, you ask them to recall all of the words to the best of their ability.

    The first group consists of 10 people who don't smoke pot or only do so occasionally. Let's say on average, people in this group would be able to remember nine out of the 15 words.

    The second group consists of people who smoked pot every single day over a period of five years. On average, they'd be able to recall 8.5 out of the 15 words.

    That doesn't seem like a huge cognitive difference, and by and large it's not. But multiply that by every five marijuana years of exposure and the gap can start to get larger. For instance, say you had a group of people who smoked weed literally every single day from age 20 until they turned 45. At age 45, you'd expect these folks to remember, on average, 2.5 fewer words as a comparable group who had smoked occasionally or not at all over the same period.

    Few people actually smoke this much pot. Among the 3,385 study subjects, only 311 (8 percent) had more than five marijuana-years of exposure. But many drug policy experts are concerned that legalizing marijuana and making it easier to get will cause rates of heavy, problematic use like this to rise.

    One important caveat is that a study like this can't determine causality. It could be the case that heavy pot use makes your short-term memory bad, or it could be that people who operate at a lower level of cognitive function are more inclined to use marijuana heavily.

    It's also worth noting that the other cognitive abilities researchers tested — focus and processing speed — did not seem to be significantly impacted by heavy marijuana use.

    The association between short-term memory declines — potentially permanent ones — and heavy pot use is very real, according to this study, and shouldn't be discounted. On the other hand, it's also quite surprising that you can smoke weed every single day for five years, and not have it impact your problem-solving abilities or your ability to focus at all.

    These findings also need to be understood in relation to what we know about the severe cognitive effects of persistent, heavy alcohol use, which include irreversible brain damage.

    Overall, the take-home message is one of moderation. Whether your preferred vice is pot or alcohol or gambling or Big Macs, it stands to reason that if you overdo it, you're going to hurt yourself.

    by Christopher Ingraham

    February 1, 2016



  1. Gradois
    There is one thing that always strikes me with drug-studies. They almost always classify subjects as either using the drug or not. There is no distinction between light use and heavy use (unless its an alcohol-study). I would think any memory impairment would be a lot worse if you smoked say 10 grams a day instead of 50 milligram.
  2. Egzoset
    Salutations Gradois,

    Even worst, since there's been "studies" practically all of those have focussed on toxic combustion-smoke flavoured with cannabis, or more precisely:
    And i heard the effects of poly-intoxication don't add up, they multiply, apparently!


    M'yeah, actually modern society "loves" our children this much teenagers still end up using fire + paper today! Go figure... Meanwhile, when one prefers the "hard" stuff he may be lucky enough to get safe-clean needles, but it all depends on multiple factors and who's running the show i would imagine.


    Not to mention after decades of bigot socio-toxic misinformation severely hurting lives, if not whole families, i finally realized the mainstream consumption method is all wrong in terms of ritual alone anyway. Briefly put cannabis has been rendered as much a nuisance as it could be possibly made as a result of abusive prohibitionist interference. Which is no scientific verdict and yet that's my own definitive opinion on the subject of "scientific" studies.


    The choice of a title about getting "stoned" sounds like déjà vu, it contributes with one more wall-of-shame sample to stare at when "Fix-my-Kid" may as well happen to be the standard prefered approach, à la Narconon, Straight Inc, etc... Amen.

    So, overall there's nothing significant here for normal loving persons to consider.

    Good day, have fun!! :cool:
  3. PeaceOfMind_
    I was a heavy hash smoker for 6 years. I noticed that my short-term memory has been affected due to my heavy use just not as much as my motivation to get stuff done has been affected.
    Habitual smoking really fucks with your motivation and without motivation you really can't acheive much.
    I envy those who can smoke daily and still get shit done.
  4. tatittle
    """This association remained even after researchers controlled for a variety of other factors known to affect cognitive performance, including age, education, use of other substances and depression."""

    The KEY word in this article is "ASSOCIATION". Too many people, including reporters and "educated" people do not distinguish between association and causation. Its the old chicken and the egg. I am gueesing the study merely located people who smoke daily, versus finding "clean" subjects to give controlled marijuana. If true, the study is not very enlightening on its own. Perhaps the people who smoke daily generally are not as bright on average. Perhaps there is adulteration which affects testing. Perhaps the smokers dont care about the testing enough to really give their best effort. The possibilities of other factors playing a role to one extent or another are endless. Which is why funding this type of work is questionable; it really doesnt tell us much at all. But hey...that means "more study" (i.e. more grants/subsidies) is needed.

    Ahh...I see this article at least points out the unreliability of the study, thats more than most writers do:
    """One important caveat is that a study like this can't determine causality. It could be the case that heavy pot use makes your short-term memory bad, or it could be that people who operate at a lower level of cognitive function are more inclined to use marijuana heavily."""
  5. Emilita
    This sounds like a really corny joke for example 'what happened when the horse walked into the bar'

    I agree with the concept everything in modersation but l have close friends who have multiple bonged house because she likes it that way and her memory is mush - you make plans and she would forget.

    I have another friend who loves her mushroom bong and uses it daily but she is sharp as a tack - nothing slips by here.

    I think it is all relative to how much, how often, bush vs hydro, ROA, so many variables but they are merely my opinions / thoughts so it's nice to see an article to get a different perspective :)
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