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Study: Marijuana and Lower IQ in Adolescents

Discussion in 'Marijuana' started by irishrose, Oct 28, 2015.

  1. irishrose

    irishrose Community Champion

    A study with around 30 years of data tracking some participants from birth to age 38 showed that heavy adolescent marijuana use permanently lowers IQ.

    Here is the article from Forbes with a link to the study:

    An adolescent's brain is still developing, and cognitive skills have not yet been fully developed. (We all know as teenagers we were tempted to do "dumb things." This is because our frontal lobe which involves decision making is still developing!) It would make sense, then that any drug use during times of brain development could potentially limit one's mental capabilities.

    With a growing culture of people who see marijuana use as acceptable, do our teens today stand a chance? Is marijuana use worth the risk?
  2. Rainman

    Rainman Community Champion

    What's even more disturbing is marijuana is one of the drugs teens/adolescents are most likely to abuse. This means that a large number of teens because they have not the knowledge that using marijuana will permanently lower their IQ will use it not knowing what it would cost them. This is why parents should always be learning about drugs because the search for information can get them something they can use to help convince their kids to stop using drugs.
  3. Rowe992

    Rowe992 Senior Contributor

    I think this whole IQ nonsense is very overrated and I for one don't use that as any quota for intelligence. I would love to see a study done in a different country before I even believe that such a thing is true. I would however suspect that a drug addict regardless of the drug would normally experience some level of brain function reduction.
  4. Waterel

    Waterel Active Contributor

    I think that any drug used too early in the young adolescent years can harm your brain, especially if it's abused every day. Marijuana doesn't make an exception to the rule. It's sad considering how many teens think that drugs are safe and permanently hinder their brain growth in their "rebellion" phase.
  5. henry

    henry Community Champion

    I don't know about lower IQ, but I do know that people who smoke weed 24/7 forget a lot. I've got a cousin who's the kind of smoker that smokes for breakfast, and every time we're speaking about something, the next time we talk, he'd forget all about it. It also happened to me, because by the time I graduated from college, I forgot most of what I studied.
    Steve Dawson likes this.
  6. Adrianna

    Adrianna Community Champion

    Well that makes sense. A child is still growing. I am sure anything like this will deter development. I don't know about permanently lowering IQ. Cells can regenerate themselves. I do believe that only a lobotomy has the capability to permanently do anything. No reason to place fear in anyone.
    JonnyMacdonald likes this.
  7. SPR012

    SPR012 Member

    Any drugs induce a physiological change to the user. These physiological changes usually stem from changes in neurotransmitter re-uptake/blockage or hormone release. Drug use, especially on a developing adolescent brain, cam be damaging. I will forever wonder how much potential was wasted if I had never touched drugs in the first place (although I have been clean for a little over a year now).
  8. 111kg

    111kg Community Champion

    That's the typical response of a drug defender. It took them 30 years of data to come to this conclusion. By the time you'll be able to see this kind of study done again, with the same data, there will be discovered a whole lot more about this drug. Why waste money on repeating the study when there is clear evidence, not to say that it should be common sense knowledge that every drug, if taken especially during the growth phase, will permanently limit the brain development.
    JonnyMacdonald likes this.
  9. JonnyMacdonald

    JonnyMacdonald Community Champion

    Good study!
    Makes sense too, if you ever talk to high people they don't seem very bright.
    Hopefully this will change some minds.
  10. zaerine

    zaerine Community Champion

    That should be well known both for parents and the teens. Agree that drug abuse especially on young ages can cause harm and affect the growth of the person mentally and maybe as well as physically.
  11. mscooke

    mscooke Member

    I agree I think a young developing brain would not have any positive benefit from marijuana or any other type of drug use or alcohol abuse.
  12. Andy_Lothbrok

    Andy_Lothbrok Member

    I cant say I'm really surprised at the study results. It is pretty widely known how bad Cannabis is to the brain and to mental health in general, particularly when abused and used frequently as a teenager. I've known many users who over several years have completely changed in their cognitive ability, whether it be forgetfulness, or just simply being unable to understand what is going on. It is very sad, because you just cant tell these people that something is happening to them because the user can never see it.
  13. Joethefirst

    Joethefirst Community Champion

    I have seen a lot of these studies, and my personal experience with people that smoke marijuana is that they tend to have difficulty concentrating, it's obvious that I am not talking about people that smoke every once in a while.
  14. Elendil

    Elendil Active Contributor

    Unfortunately, brain cells don't. Once they're damaged/dead, they stay that way. (That's the reason neurological disorders are so hard to treat.) :(

    Personally, I also think that IQ stuff is overrated, and with a separate study that claims that it has no particular effect on IQ, the debate among researchers is still going on. The latest study, done by a team of US researchers, however, tells that marijuana smoking decreases the 'size' of the brain but increases the 'density' but increasing the intracellular connections.
  15. guitarmom1279

    guitarmom1279 Member

    I do for one believe there is something to this theory. My ex has openly admitted to smoking MJ for many years and I can definitely see the effects it has cause him. He has lots of brain fog and at times is just down right dumb. He will come of with some very stupid things that may not make any sense. I can clearly see that there is lots of truth in the theory that it kills brain cells,and ofcourse once you have lost them you can not re develop them.
    DG. likes this.
  16. DG.

    DG. Member

    They get addicted because of friends peer pressure mostly... drugs reduce tension and give relief I totally agree... but having it all the time especially cannabis increases heartbeats and can lead a heart attack... so be careful.. :)
  17. thash1979

    thash1979 Active Contributor

    Well they spent all this time and money studying teen use of marijuana and the effects on their brain, but did they ever do the study considering the alarming percentage of kids being diagnosed with ADD or ADHD? And did any of the kids they were testing in this study of marijuana use, take any other prescription drugs for ADD or ADHD. In my opinion, it is not the marijuana parents need to be concerned about, it is the prescription drugs they are basically handing out to our youth, telling them that they have a learning disability. How do the people behind the study know that the kids they studied didn't have any other underlying problems. Sounds like a bunch of garbage to me. Maybe children these days aren't being taught the same way they were 20 years ago and that is the reasoning behind the IQ drop. Or the fact that technology and cell phone use has made social interaction almost obsolete. Quit blaming problems of our kids on marijuana use.
  18. explorerx7

    explorerx7 Senior Contributor

    I don't know why this obsession with trying to stigmatize marijuana. I can testify from experience I where have seen some of the brightest minds being constant marijuana users: lawyers, doctors, professors, engineers, and it has not in any way affected their mental capacity, in fact, they have been users even before they had obtained their qualifications.
  19. Vinaya

    Vinaya Community Champion

    I checked the report published on Forbes and found it very alarming. These days many people are vouching for legalization of marijuana however, they must be aware about the consequences of taking this recreational drug. As far as I know, marijuana also has adverse effects on body.
  20. Damien Lee

    Damien Lee Community Champion

    From what I'm aware, most substances have adverse affects on the human brain. This is one of the reasons why I decided to fight my ecstasy addiction, as there were studies done on how damaging it is on the brain after a period of time. It doesn't really surprise me that marijuana use will lower IQ eventually.