Marijuana

What We Don't Know About Marijuana's Risks and Benefits

It fills a new book from the National Academy of Sciences.

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NAS

The last time the National Academy of Sciences issued a report on marijuana, three states allowed medical use of the drug. Eighteen years later, there are 28 states that recognize marijuana as a medicine, and eight of them also allow recreational use. But as a new NAS report published yesterday shows, there are still big gaps in our knowledge of marijuana's risks and benefits.

The 1999 report, commissioned by a drug czar who insisted there was no evidence that marijuana is medically useful, refuted that claim but highlighted the paucity of relevant research. "The accumulated data indicate a potential therapeutic value for cannabinoid drugs, particularly for symptoms such as pain relief, control of nausea and vomiting, and appetite stimulation," it concluded.

The new report, which takes into account studies conducted during the last two decades, is less tentative but still finds the evidence for most medical applications inconclusive. "We found conclusive or substantial evidence…for benefit from cannabis or cannabinoids for chronic pain, chemotherapy-induced nausea and vomiting, and patient-reported symptoms of spasticity associated with multiple sclerosis," the authors say. "For these conditions the effects of cannabinoids are modest; for all other conditions evaluated there is inadequate information to assess their effects."

The report notes that investigation of marijuana's medical utility has been constrained by legal and bureaucratic barriers, including continued federal prohibition and the Drug Enforcement Administration's refusal to license more than one producer of cannabis for research. "There are specific regulatory barriers, including the classification of cannabis as a Schedule I substance, that impede the advancement of cannabis and cannabinoid research," the authors say. "It is often difficult for researchers to gain access to the quantity, quality, and type of cannabis product necessary to address specific research questions." Last August the DEA once again refused to reclassify marijuana but agreed to start accepting applications from additional marijuana producers.

As state-legal marijuana products proliferate across the country, federal prohibition prevents scientists from investigating their properties:

Cannabis concentrate sales doubled in Colorado from 2015 to 2016, reaching $60.5 million in the first quarter of 2016, and yet current federal law prevents chemists from examining the composition of those products as it may relate to safety, neuroscientists from testing the effects of those products on the brain or physiology in animal models, and clinical scientists from conducting research on how these products may help or harm patients. And while between 498,170 and 721,599 units of medical and recreational cannabis edibles were sold per month in Colorado in 2015, federal law also prohibits scientists from testing those products for contaminants, understanding the effects of these products in animal models, or investigating the effects in patient populations.

Regarding the potential dangers of these products, the report is mostly reassuring, finding little or no evidence that marijuana impairs the immune system or increases the risk of heart attacks, lung cancer, or chronic obstructive pulmonary disease (contrary to the claims of anti-pot activists). Regular pot smoking seems to worsen bronchitis symptoms, and marijuana consumption by pregnant women is associated with lower birth weight, although there is little evidence of a link to pregnancy complications or postnatal health problems.

Marijuana use is associated with schizophrenia, suicide, poor academic performance, and abuse of other drugs, but the causal relationships remain murky. The report says "there is limited evidence of a statistical association between sustained abstinence from cannabis use and impairments in the cognitive domains of learning, memory, and attention"—i.e., effects that persist long after people have stopped using marijuana, which remains a subject of much controversy.

The report notes that marijuana legalization has been followed by increases in accidental ingestion of cannabis by children, which is usually not medically serious but can depress respiration. Another concern about legalization is its impact on road safety, since "there is substantial evidence of a statistical association between cannabis use and increased risk of motor vehicle crashes."

Laboratory tests indicate that marijuana impairs driving ability, although not as dramatically as alcohol does. Measuring marijuana's impact on actual car crashes is difficult, however, not least because studies generally equate a positive test for marijuana with intoxication, treating sober drivers as if they were stoned. The report notes that a 2016 review of the research suggests marijuana has a "low to moderate" effect on crash risk, increasing it by 20 or 30 percent (compared to an increase of about 400 percent for drivers with a blood alcohol concentration of 0.10 percent). But it's not clear how many of the drivers who were deemed to be under the influence of marijuana in the studies covered by that review had consumed it recently enough that they were still feeling the effects.

For the most part, this report seems like an honest and careful attempt to grapple with what we know and don't know about marijuana, which means neither prohibitionists nor cannabis enthusiasts will be completely happy with it (although both will mine it for ammunition). The authors are generally careful about drawing causal conclusions from statistical associations.

But not always. The report says "cannabis use is likely to increase the risk for developing substance dependence" involving other drugs, a quote we surely will be seeing in anti-pot propaganda hyping marijuana's "gateway effect." Later in the same chapter, however, the authors concede that all we really know is that "there is moderate evidence of a statistical association" between cannabis consumption and abuse of other drugs. That's why "additional studies are needed to determine whether cannabis use is an independent risk factor for, or causally contributes to, the initiation or use of and dependence on other drugs of abuse later in life."

While I welcome the self-correction, I doubt research will ever resolve this issue. Scientists can (if regulators let them) conduct a randomized, double-blind study to see whether cannabis extract is effective at controlling seizures or treating irritable bowel syndrome. They cannot legally or ethically conduct such a study to see whether smoking pot makes teenagers more likely to become heroin addicts.

As researchers like to say, more research is needed, especially in an area where the government has systematically discouraged it. But research cannot solve every puzzle.

NEXT: A reassuring choice for deputy attorney general

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  1. So what. I either get to decide what goes in my body or I don’t.

    1. THERE. ARE. LIMITS.

      For instance, you don’t get to put Sullum’s weed into your body.

    2. You can’t make the decision. You know who can ? Top. Men.

  2. Pot is just fine.

    What scientists need to be doing is measuring the effects of seeing Lena Dunham’s nasty ass, ever.

    I caught a glimpse of her in a headline this morning.

    She is the most repugnant, skank that has ever whored herself.

    Sorry to bring this up but if we are going to talk about nonsense, then at least we can open a discussion about some of the grossest humans that have ever lived. What person did she blackmail to get a job?

    1. Let’s live in the real world, and talk real-world impacts, shall we?

      “What scientists need to be doing is measuring the effects of seeing Lena Dunham’s nasty ass, ever.”

      The impact of seeing said ass, for uncontrollably horny youngsters with no taste whatsoever, is that the “hook up” with said ass, get venereal diseases, and then “society” has to pay higher medical costs. Therefor, Lena Dunham’s nasty ass should be forever locked up and inaccessible!

      With respect to “pot”, it leads to incarceration, and then to butt-fuck-rape, and AIDS? So again, this increases medical costs. “Pot” should therefor be eliminated by the release of a gene-edited “pot ” plant with a deadly “gene drive”. Problems solved!

    2. “She is the most repugnant, skank that has ever whored herself.”

      Snooki has a sad.

      1. I have more respect for Snooki – she was born stupid. Duhnam is…*shudder. Excuse me, I can’t finis….

  3. I doubt research will ever resolve this issue

    Ye of little faith. (And now you know why Obama could never completely legalize it. He did the best he could.)

    1. I’m sure Obama never gave a shit about whether it was legalized or not. He was a fence rider on everything until he could gain from taking a stance.
      A chicken shit of the highest order.

      1. The chicken shits shall inherit the earth.

  4. I still think it was a mistake for the 21st Amendment not to repeal that portion of the 18th Amendment which made marijuana illegal.

  5. “cannabis use is likely to increase the risk for developing substance dependence” involving other drugs

    Sorry but what the hell even is a substance dependence? Now see, that’s part of the problem with you people. Don’t believe everything people call you an idiot for if you question it. In fact, that’s kind of a red flag.

    1. The report says

      He quoted the fucking report. That’s the problem with us people, that someone quoted someone else’s report? Piss off, troll.

  6. But research cannot solve every puzzle.

    Jesus Ronal’d Bejlij wept.

  7. Spell casting may lead to sorcery later in life

    Researchers are split! We need more Science? to investigate this pressing issue!

  8. Is there a chapter in there about how vaping the devil weed causes skin failure? Because whatever we know or don’t know about marijuana use, we do know for sure that vaping is the most dangerous thing you can do next to playing Russian roulette with a semi-automatic.

  9. And how are my precious FrankenTrumpkensteins? doing today?

    1. Dang it, I am NOT yer precious FrankenTrumpkensteins! I have some quite mixed feelings about and for the Donald?

      This is what I’d say to Him if I ran into Him tomorrow:

      (Sternly!)
      “Now look, Donald, I’m sick and tired of yer shit!!!”

      (Slyly)
      “?Now can I have some of yer piss?”

  10. which means neither prohibitionists nor cannabis enthusiasts will be completely happy with it (although both will mine it for ammunition).

    I, as an “enthusiast”, don’t need to mine jack shit. The burden of proof rests with the prohibitionists and so far they’ve gotten by without having to prove one god damn thing for over a century in some places while their bans have remained intact and relatively unchallenged. They ought to legalize it immediately and then make their case to ban it again as it should have been done in the first place. If their case is strong, they should have no trouble doing so. But most of us know by now that their case is exceptionally weak.

  11. “The report says “cannabis use is likely to increase the risk for developing substance dependence” involving other drugs, a quote we surely will be seeing in anti-pot propaganda hyping marijuana’s “gateway effect.””

    These arguments just grind my gears. There is absolutely no way to ever prove, or disprove, a drugs gateway effect. There are situations that, to a dumbass who has no desire to actually think, would appear to be causality to a gateway effect. The truest gateway effect is in fact perpetuated by the government and their prohibition. If instead of being able to go to my local cannabis shop and purchase my legal weed, I must go to my local gangbanger to get my weed. While there, he begins offering his other merchandise at which point I may be tempted to try heroin, and boom, I’m addicted.

    And I would also argue that a person who is willing to try drug A would be just as likely to try drug B, if offered drug B first. Drug A and drug B could be any given drug and trying/using one has no correlation to trying the other.

    1. And I would also argue that a person who is willing to try drug A would be just as likely to try drug B, if offered drug B first. Drug A and drug B could be any given drug and trying/using one has no correlation to trying the other.

      I think not. If I go in search of drug A, marijuana, but all that is available is Drug B, say… crystal meth, why in the fuck would I go for the crystal meth?

      “Well I couldn’t find this rather mild drug I wanted to try, so I suppose I’ll settle for this noxious concoction of Draino, gasoline and assorted cleaning products that I’ll inject directly into my cock.” ….. that doesn’t seem like a terribly improbable escalation to you?

      I mean shit, if the liquor store is closed, do I start huffing duster and snorting bath salts? I’m sure there’s some people who would do that, but then clearly they have some problems that do not relate in any way to the opening hours of the liquor store.

      1. “If I go in search of drug A, marijuana, but all that is available is Drug B, say… crystal meth, why in the fuck would I go for the crystal meth?”

        Um…because it is super fun?

        1. I think the overlap of meth heads willing to smoke pot is higher than the overlap of potheads willing to use meth, by leaps and bounds.

  12. Some weed would help this hangover.

    I’ll also take being put down like a sick puppy : /

  13. What’s happening, good websites you possess at this time there.
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