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>We are already seeing studies that show regular marijuana use is correlated with permanent decreases in intelligence, memory loss, motivation, and mental healt
by Tenoke 5y ago
>We are already seeing studies that show regular marijuana use is correlated with permanent decreases in intelligence, memory loss, motivation, and mental health.
I can maybe believe it but I am yet to see a convincing Meta-Analysis or at least a large RCT. In general, people seem to recover from a lot of drug usage if they stop for long enough and weed isn't one of the heavy ones. Can you share what studies you are referring to?
- legitster 5y agoThe study in the linked article found that lead reduced the IQ of exposed Americans 3-6 IQ points. A New Zealand study found that persistent cannabis users had a 6-8 point decline, even if they had given up cannabis: https://www.pnas.org/doi/abs/10.1073/pnas.1206820109 https://www.pnas.org/doi/abs/10.1073/pnas.1206820109 Here's a meta review that found a 2 IQ point drop across a wider range of usage types: https://www.cambridge.org/core/journals/psychological-medicine/article/intelligence-quotient-decline-following-frequent-or-dependent-cannabis-use-in-youth-a-systematic-review-and-metaanalysis-of-longitudinal-studies/26BEC9CBD2A39010C26100278F8CA813 https://www.cambridge.org/core/journals/psychological-medici... There's a lot less known about cannabis at this point, but what we know so far isn't very positive.
- arcticbull 5y agoThat's not actually what the study found. Further, cessation of cannabis use did not fully restore neuropsychological functioning *among adolescent-onset cannabis users*. They did not find a 6-8 point decline for folks who gave up cannabis if they started later in life. In fact they found no decline in IQ whatsoever for folks who started later in life - both when using it and after stopping. In contrast, within-person IQ decline was not apparent among adult-onset persistent cannabis users who used cannabis infrequently (median use = 6 d) or frequently (median use = 365 d) in the year before testing. > There's a lot less known about cannabis at this point, but what we know so far isn't very positive. ... for adolescents. Both your studies only show impact in youth.
- staticassertion 5y agoSorry, I took a look at the study and I couldn't tell - what is an adolescent? Like, 10-18? 14-25? I know what the word means, but for a scientific study I assume there's a specific range they're referring to.
- legitster 5y agoI don't think my summary was unfair. I was only asked if there was evidence for persistent effects. There clearly is, even if just for adolescents. It's also important to point out that for the adult-onset group they only looked at 1 year back. This doesn't preclude the possibility that longer periods as an adult find different results.
- deleted 5y ago[deleted]
- mynameisvlad 5y agoYour summary missed a critical piece, which is that it is just for adolescents. I don't think, even within the marijuana community, that there is any debate that marijuana use in adolescents is harmful. I regularly see /r/trees comments telling teens to stop until they're at least 18 and their brain finishes developing.
- mandmandam 5y agoSorry, no, your claims and summary were definitively and unquestionably false. There is a large, large difference between 'Americans' and 'adolescents'. Vast.
- Tenoke 5y agoI hadn't seen the meta-analysis, thanks. 2=3 IQ points drop is pretty significant and enough to be worth consideration but it's not too worrisome.