Health Risks of Marijuana Use

Let's Talk Addiction & Recovery Podcast
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While the long-term public health impact of marijuana legalization is yet to be determined, many experts agree that marijuana use is risky for some people and addictive for others. Listen in as host William C. Moyers talks with psychiatrist Marvin D. Seppala, MD, about the health risks of marijuana (especially for teens), the difference between heavy use and marijuana addiction, and how to find help if you're concerned about marijuana use or dependence.

One of the main things that marijuana affects in regard to health is our cognition—how we think.

Dr. Marvin Seppala

0:00:14 William Moyers
Hello and welcome to Let's Talk, a series of podcasts produced by the Hazelden Betty Ford Foundation on the issues that matter to us and the issues that we know matter to you, too. Prevention, research, addiction, treatment and recovery support. I'm your host, William Moyers, and today we're joined by the Chief Medical Officer of the Hazelden Betty Ford Foundation, Dr. Marvin Seppala. Marv, welcome.

0:00:40 Dr. Marvin Seppala
Thanks, William. Glad to be back.

0:00:42 William Moyers
Always good to be with you as a fellow traveler who's been walking this walk for a long time now at Hazelden Betty Ford. And even before that. In the real world.

0:00:50 Dr. Marvin Seppala
Yeah, it's always a treat.

0:00:52 William Moyers
Yeah. Today we wanna talk to you about health risks of marijuana use. And I wanna just cut right to the chase Marv and ask you, is marijuana a gateway drug?

0:01:02 Dr. Marvin Seppala
So it depends on how you define gateway drug. Because we called it a gateway drug for a couple of decades and all of a sudden there was some research that said well, you know, milk, yeah it—almost everyone who ends up on opioids and cocaine drank milk at one point in their life. So it's an association that's not absolute. And yet since then, people have reexamined it again and now, you know, we call it a gateway drug. Because almost everyone who goes on to the more problematic substances, the opioids, heroin, cocaine, the stimulants—has used marijuana. And they get exposed to a culture of use of other drugs. And so there are risks associated with marijuana that put people at risk for using these other substances as well.

0:01:52 William Moyers
What are the health risks of marijuana?

0:01:55 Dr. Marvin Seppala
You know the health risks of marijuana start with concern about lungs, right? There's been a new kind of accumulation of all of the research data that came out in 2017 that was written up by the Academies of Science, Medicine, and Industry. And in that kind of review, they said that there's no evidence at this point in time of lung cancer, of COPD, or other major lung illnesses associated with marijuana use. Which surprised me. Because I've been waiting to hear that it causes cancer for years. And it's a hard thing to study. 'Cause in the past anyway, most people who smoked marijuana also smoked cigarettes.

0:02:39 William Moyers
Ah, yes.

0:02:40 Dr. Marvin Seppala
Really confounding the data. But, currently they say no, but it does cause a chronic cough and bronchitis.

0:02:49 William Moyers

0:02:50 Dr. Marvin Seppala
Things we used to know tobacco did before we knew it caused cancer. So, maybe there's a risk, maybe there isn't, we don't know yet.

0:02:58 William Moyers

0:02:58 Dr. Marvin Seppala
It does increase the likelihood of psychosis and schizophrenia. Almost doubles the likelihood.

0:03:06 William Moyers

0:03:07 Dr. Marvin Seppala
Doubles. It's still very low; it's a one percent type thing to two percent. But doubling the risk of a severe mental illness really debilitating lifelong mental illness, that's a big deal. And it's an association again. It's not been known to absolutely cause it, but the more you smoke marijuana, the more, you know, the more frequently the higher the amount, the higher the likelihood that you get this type of psychosis or schizophrenia. So that is a big deal. One of the main things that marijuana affects in regard to health is our cognition—how we think. And learning, memory, and concentration are affected for a 24-hour period after the use of marijuana. It's pretty cut and dry. So we know there's an acute difficulty with how we think and what we remember for 24 hours. There's not been evidence of long-term changes that have been absolutely nailed down in the research. Now, do they occur? Maybe, maybe not; we just don't know yet. Nonetheless, if it lasts for 24 hours, and you're using every day, it's kind of [laughs] happening all the time, you know? And there has been some studies that suggest diminished IQ. In a recent study just published last year suggested that minor changes in IQ over time with people who smoked a lot of marijuana chronically. So really the jury's kind of out but we absolutely know that for a 24-hour period it's a problem. And like ten, twelve years ago, there was an Australian study. Pilots, airplane pilots, they put 'em in simulators. And they were naïve to marijuana which is an important point because you know you get used to things.

0:04:52 William Moyers
So you mean when you say they're naive they hadn't used it—

0:04:54 Dr. Marvin Seppala
They never used marijuana. And they're used to being in simulators. They had to do it regularly. And pass tests and stuff. So they'd put 'em in the simulator after they smoked marijuana and everything went well until they threw in something really unusual or novel. And then they failed every time. They brought 'em back 24 hours later and the only reason I bring this up is this 24-hour period. They brought 'em back 24 hours later and the same exact thing happened. They flew well, the simulator, everything's fine, until they threw in some like an engine goes out or something weird that was really dangerous. And they couldn't respond, they failed it every time. Really consistent with this new data that suggests for a 24-hour period your ability to remember things, to learn things, to concentrate on things, is truly affected.

0:05:42 William Moyers
What about teens and marijuana though? We know that there is proof of the harmful effects of marijuana with teens, correct?

0:05:51 Dr. Marvin Seppala
We do know that the earlier you start using any substance, marijuana included, the higher the likelihood of addiction. And as a result of that, you know, teen brains aren't gonna fully mature until their mid-twenties. All this changes in brain function and how the brain's developing affected by a really powerful medication or drug like marijuana alters how the brain develops. And so yes, it does change, and part of that change is to put people at risk for addiction later on.

0:06:28 William Moyers

0:06:29 Dr. Marvin Seppala
And you'd have to argue that if for 24 hours it's affecting learning, memory, and concentration, that it potentially could do that for a longer period even though that hasn't been proven yet. But you have to wonder.

0:06:41 William Moyers
Now I'm sitting here thinking that some of our viewers and listeners are chuckling because they're saying oh come on, Dr. Seppala, come on, Moyers, we smoked marijuana back in the old days, what's the difference between back in the sixties and seventies and now? But there it's actually a big difference at least when it comes to the potency of marijuana. Can you speak to that?

0:07:01 Dr. Marvin Seppala
Truly, remarkably different. So, marijuana purchased on the street when we were young, probably five percent THC. And THC is the active ingredient that causes intoxication associated with marijuana, cannabis, whatever you wanna call it. Nowadays, on average, especially in the states that have legalized it, it's 25 percent on the marijuana. And that's actually a low number. The people that are really connoisseurs or whatever you wanna call it they want averages way, way higher. And you can buy edibles and concentrates and waxes and all these different types of THC products where the percentage is almost one hundred percent. It's well above 90. So dramatic difference in the potency of that substance. In fact to the point that I made earlier about psychosis and schizophrenia, a lot of people get paranoid from marijuana. Well really high doses, it's a lot more likely! Because it's just so powerful.

0:08:00 William Moyers
Now I know your perspective is grounded in all of your years as the Chief Medical Officer, as a psychiatrist who's a real leader in the field of addiction medicine. You also have a personal experience many, many decades as a man walking that walk in recovery. So I know you're biased obviously, you can't help it; we all are, based on our own experiences. What do you say to people in the states that have legalized marijuana? We know at Hazelden Betty Ford that we are opposed to the legalization of marijuana although we have refined our position, have we not?

0:08:34 Dr. Marvin Seppala
We have. And in those states that have legalized recreational marijuana, they did nothing to protect our youth. And that's my main concern. It's more likely to cause damage in our youth, it's more likely to alter people's lives when they start young, it's more likely to result in addiction when they start young. And none of those laws put into position something that would protect our youth. You know the whole West coast and British now all of Canada, but it was just British Columbia have legalized recreational marijuana. And none of those states did anything about this. And put into place you know some of the proceeds to provide treatment or intervention services or even just education for our youth. Because you know historically, NAIDA has looked at perception of risk associated with marijuana for decades. And among our youth, when perception of risk goes up, so our youth recognize that it's problematic to smoke marijuana in some way, they are less likely to do it. When perception of risk goes down, they're more likely to do it. And that graph is just consistent over time. And so, if you legalize something, perception of risk drops, right?

0:09:52 William Moyers
Sure. [nods]

0:09:53 Dr. Marvin Seppala
Our youth think ah, it must be pretty safe. And as a result more are going to seek it out and use it. And since we didn't put in those protective sort of aspects, from a regulatory standpoint, there will be consequences to our youth as a result. There will be over time more use.

0:10:18 William Moyers
What about medical marijuana though? What about the people who say gosh you know for chronic pain or palliative care, marijuana is a really invaluable tool in managing chronic pain? Is there a role in medicine for marijuana or is there a role in managing chronic pain for marijuana?

0:10:37 Dr. Marvin Seppala
There's pretty good research evidence that shows that marijuana does limit pain. Does reduce pain. So, it really could be the case, but there's not adequate research to understand what that means at this point in time. And so, is it THC, the active intoxicating ingredient to the marijuana, is it another type of cannabinoid, CBD, that does it? Is it a combination of those things? There's over 300 different chemicals in cannabis, so, could it be something else we don't even know about yet? And the government schedules marijuana as a Schedule 1 substance, which means it has no medical utility and it's extremely dangerous. You know both of which aren't necessarily true. Because it looks like it actually works for pain and we know that it isn't that dangerous. It's dangerous, it has a potential for addiction, it has some side effects, but it's not dangerous like the other Schedule 1 substances, like heroin, for example. You know, the medicine, the LSD, the things we cannot legally use!

0:11:47 William Moyers
Sure. Sure. Right.

0:11:49 Dr. Marvin Seppala
So it's remarkably absurd and it limits research. Because if it's Schedule 1, as a researcher at some academic medical center, you can't just go buy some marijuana and study it. You've gotta go through the government to get the appropriate licenses to be able to do this and they restricted it over time. Which has resulted in a lot of research about risks because that supports—

0:12:17 William Moyers
Sure. Sure.

0:12:17 Dr. Marvin Seppala
You know how the federal government has looked at this over time. And hardly any research about benefit.

0:12:22 William Moyers

0:12:23 Dr. Marvin Seppala
Which means when I say you know there is evidence of benefit in pain, it's from a small amount of studies using marijuana itself. And not, you know, some of the chemicals in marijuana to really try and define what works and—and figure that out.

0:12:40 William Moyers
Mmm-hmm. Mmm-hmm.

0:12:42 Dr. Marvin Seppala
So it tends to work for pain. It can help with people that have cancer chemotherapy agents for nausea and vomiting. So that they have an appetite and can eat. And that's been pretty well shown. And then folks with multiple sclerosis who get really tight muscles, you know.

0:12:59 William Moyers

0:13:01 Dr. Marvin Seppala
Can't move smoothly anymore. It actually can help reduce that. That literature is pretty solid too. There's some other effects that it may be beneficial for.

0:13:13 William Moyers
But what about in the treatment of opioid use disorder, is there any role for marijuana?

0:13:17 Dr. Marvin Seppala
No, that's just a fallacy that I think you know—big business is behind marijuana now. It's huge now.

0:13:25 William Moyers
Yeah. Traded on the public—on the stock exchange.

0:13:27 Dr. Marvin Seppala
Yeah, it's described as a billion-dollar industry, right? And so, the more they can convince us it's beneficial for such things, the more people will use it. And there's just not good evidence that it helps at all for opioid use disorders. In fact the opposite is true. We know that from several studies actually, mostly outside of the United States but not entirely, that Australia was one of the places where some of these were done that showed that ongoing use of marijuana actually resulted in more use of opioids, not less.

0:14:01 William Moyers
Hmm. Interesting. [nods]

0:14:03 Dr. Marvin Seppala
And didn't necessarily help with chronic pain. And that's the issue with the opioids. That they're incredibly useful for acute pain like after a broken leg, after surgery, for just a few days to a couple weeks. Remarkably beneficial and if done right, a very low likelihood of addiction—

0:14:24 William Moyers

0:14:24 Dr. Marvin Seppala
'Cause you're only using them for a short period. Chronic use of opioids for months and years, that's where the—

0:14:30 William Moyers
Right. [nods]

0:14:31 Dr. Marvin Seppala
Addiction rates skyrocket.

0:14:33 William Moyers

0:14:33 Dr. Marvin Seppala
And the data suggests that marijuana doesn't really help for chronic pain. Maybe it does, maybe it doesn't—we don't know. We haven't had enough studies to really figure it out. But hopefully people will be able to start studying it a whole lot more now that it's getting more acceptance.

0:14:50 William Moyers
Well marijuana's certainly a contentious topic. One that we thank you for bringing your expertise to and your insights to today. Dr. Marvin Seppala, the Chief Medical Officer of the Hazelden Betty Ford Foundation. I'm William Moyers your host and we thank you for joining us for another edition of Let's Talk, a series of podcasts on the issues that matter to us and we know matter to you, too. Please join us again for another edition.

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