Over the last decade, cannabis use has been legalized in more states. At the same time, the idea that marijuana is a safe drug has steadily increased. But is this an accurate perception? Recent research by Dr. Ryan Soltan casts some doubt on a universally affirmative answer to that question. And he says we need to be having a more objective, balanced, and nuanced conversation around cannabis than we currently are.
00:24:15.800You know, it's as compelling as what we're talking about now, a bit to me more disturbing in some ways.
00:24:22.060So schizophrenia is like a super serious condition.
00:24:25.800It's a neurodegenerative disease and it really alters a person's life course.
00:24:32.740And it significantly affects their family members.
00:24:35.460So it's really something that we want to be doing everything we can to prevent.
00:24:39.660Because once someone has it, our treatments for schizophrenia are, they're fine and they help, but they're really not great.
00:24:47.660Like out of all of our mental health conditions, it's probably one of the ones that we have the poorest ability to treat.
00:24:53.100So, you know, in thinking about how to prevent that, there's just been this thing that we've noticed for a long time, which is that people, when they first develop schizophrenia, which tends to develop like late teenage years to around 30, that the likelihood that that person has a positive urine drug screen or reports recent cannabis use is like really, really high.
00:25:15.980And in fact, when I have a new episode of schizophrenia or psychosis, we could generally describe it as, I mean, it's the exception, not the rule when you test their urine and it's not positive for cannabis.
00:25:28.440So we noticed this link, and there's been multiple studies, there was just another recent study on this, where it looks like in, certainly in guys, this is more true for men, between the age of like, I think 18 to like 26, cannabis use increases the likelihood of this development of schizophrenia by four times.
00:25:51.440I mean, for me, one of the things I talk about, because I work with a lot of young people, and when they're using cannabis, or if they're thinking about it, my thought is always like, look, if you want to use cannabis, that's your decision, like, okay, but like, if you want to go off the scientific research, it actually would say that you should wait until you're around 25.
00:26:09.300This risk of schizophrenia drops really substantially, the association between cannabis and schizophrenia is not nearly as strong later on.
00:26:19.220And the idea is like, your brain is still developing, getting back to this, my brain is not developed, my brain is not developed, like, you know, schizophrenia is very much a disease of your brain, a condition of your brain.
00:26:27.820And so, when you have cannabinoid receptors, which are these receptors that we all have, that cannabis binds to, and by the way, we all have our own internal cannabinoids that your system just makes on their own, right?
00:26:39.280Just like you have testosterone, and you could take exogenous testosterone, you're taking exogenous cannabinoids, they're actually much stronger than your cannabinoids, and there are these receptors all over your brain.
00:26:48.680And so, when your brain is developing, you know, it's easy to see how exposure to these things is going to disrupt the development of your brain, and potentially increase the risk of depression, anxiety, definitely schizophrenia, and certainly also the risk of not being able to manage substance use later in life.
00:27:07.680Because, you know, one of the things that I think we all struggle with is, you know, okay, you can drink alcohol, but can you drink alcohol in a way that it is overall giving you a net gain in your life?
00:27:20.160And so, what's that question with cannabis?
00:27:21.920Like, where do we sort of draw that line in terms of what is an appropriate amount that people are using, and what is an age to start at?
00:27:29.840So, when I talk about this with youth, I really encourage them to wait until, like, 25, because the science really says that your brain is now done developing at that time period, and the likelihood that when you're an adult, that if you use alcohol, if you use cannabis, or use another substance that's potentially addictive, that you use it in a healthy way, meaning, like, it doesn't end up causing problems in your life, is much, much, much higher the later you start.
00:27:55.800The earlier you start, the likelihood that it's a problem is significantly higher.
00:28:01.840Okay, we've been talking about there's a correlation causation, there's research that there is a causative factor going on.
00:28:07.640So, you mentioned what might be going on, so these cannabinoids are somehow disrupting the developing brain.
00:28:13.420Like, do we know exactly what's happening to the brain, particularly a young person's brain that, you know, the THC or whatever it is, disrupts the development?
00:28:22.600Like, do we have an idea of what's actually going on?
00:28:24.480Well, we have a pretty good idea around it.
00:28:26.780I mean, your brain's development is, I mean, it's, the levels of complexity around it are mind-boggling.
00:28:33.960I've been in training for mental health and neuroscience and the brain for many, many, many years.
00:28:40.660I guess it probably started for me in, like, 2007.
00:28:44.420I have been in a research track on this now for five years, and I'm still learning around the complexity of that.
00:28:50.620But, like, very broadly, very broadly, the cannabinoid receptors play a role for teens in what happens to your brain and how it develops.
00:29:01.580How much gray versus white matter that you have?
00:29:04.460The morphology and size of different parts of your brain.
00:29:07.860And there are a lot of studies, I was actually just flipping through it before we got on, that consistently show changes in the morphology of the brain, as well as tests that test how well your brain is working.
00:29:22.360Like, how quickly can you think of something?
00:29:25.660Very consistently shown in everything from rodent models through actual people.
00:29:32.760And so, when, in science, you keep finding the same or similar things in different places, that's usually a really good signal that there's something going on there.
00:29:42.140So, when you say morphology, is that like the size of the brain?
00:30:38.920So, like, the likelihood of having depression.
00:30:41.880The likelihood of having suicidal thoughts.
00:30:44.880The likelihood of having poor academic performance.
00:30:47.980The likelihood that you go on to actually have a substance use problem, right?
00:30:53.700Is all very highly linked to when you start using.
00:30:58.400Let's say, you know, there's a person who started using cannabis 15, 16.
00:31:04.720They got really into it and then they stopped.
00:31:07.780Is there a risk of increasing mental deficits or mental illness later on in life?
00:31:12.720Is it still going to be higher than if they'd never used the stuff?
00:31:15.800Yeah, I think we can say pretty confidently that they put themselves on a different trajectory, but that the decision to sort of limit that use later is also putting them on a different trajectory than if they had stayed on that.
00:31:28.700There's one study that shows that long abstinence, like eight years, that the brain seems to heal itself.
00:31:34.580And that in that eight-year time period, which is like a long time, that their brains looked fairly similar to controls.
00:31:44.400There were some differences, but there is some healing that goes on, which is cool, right?
00:31:48.140Like, we used to think that the brain, I was taught in high school, like, your brain can't regenerate, it can't regrow, but that's actually not true.
00:32:13.580Yeah, I mean, this is like one of the things I wish actually, people want to talk about, like, the mental health from, like, a depression, suicidal, schizophrenia point of view, and those are super important.
00:32:22.060As a person who is sub-specialized in, like, child and adolescent psych, I think a lot about learning and development from a learning point of view.
00:32:32.140And, you know, your job, until you are 18, your primary job is to go to school.
00:34:02.180I think at a basic level, there's a whole group of people that feel incredibly validated now that something that was demonized for so long is being given credit as at least not being the incredibly detrimental drug that it was portrayed as.
00:34:24.200Like marijuana is not as evil as we were told historically that they're right about that.
00:34:30.440But, you know, I think that that's one aspect of it.
00:34:33.660I think another aspect of it is that there's a lot of people that are trying to capitalize on this, you know, from a development of products point of view in the U.S.
00:34:43.080So there's a lot of PR being done around marijuana.
00:34:48.440And so people are becoming more comfortable with it.
00:35:03.620But for me, as someone who's thinking about this, I think a little more bird's eye view than the general public, I think that we are, the pendulum has now swung too far to the other side.
00:35:17.320And that we need to sort of step back and start saying, wait a second, like marijuana is actually not a panacea treatment for everything.
00:35:28.460That we need to be thinking about what are appropriate limits and sets of limits.
00:35:33.240Also, what are quality control things?
00:35:34.600So the meeting I had yesterday that I was mentioning to the people who had said they had used at different ages,
00:35:39.440one of the things we're doing is actually trying to use advanced organic chemistry methods to take samples of marijuana and evaluate essentially the purity of them, the quality of them.
00:35:55.420You know, how much of them is actually the THC cannabis or CBD product that it's supposed to be and how much of it is other stuff?
00:36:01.640And our preliminary results suggest that it's much more heterogeneous than you would like it to be, as opposed to alcohol, which is not.
00:36:11.740It's alcohol is highly regulated and you know what you're getting and you're not going to go buy alcohol at a liquor store and be worried that it's poisoned with something.
00:36:20.760Yeah, it's laced with fentanyl or something like that.
00:36:52.300You know, what things are being added on?
00:36:53.960And that's happened already and hit the news.
00:36:56.600Like, if you remember the whole vaping thing that happened, where all these people were getting these lung illnesses from vapes, and they were putting some sort of, I can't remember what it was, but some sort of compound that they were using to sort of like clean or extract it was incredibly toxic.
00:40:29.620My concern is lung diseases across the board, particularly in youth, the earlier you start.
00:40:35.760My concern is that it is halting the development of whole groups of kids that are not going to progress in their life in the same way that they would have.
00:40:46.880Because they're more likely to have these mental health conditions, because they're less likely to be engaged appropriately in their scholastic environments, because they're having cognitive problems.
00:40:59.860And that that's really unfair to them.
00:41:02.220You know, and I feel like, you know, I'm going to get on a soapbox for a second here.
00:41:05.920I feel like we're failing them as a society, you know, by permitting that to occur.
00:41:11.500And there's a lot of parents that are not concerned about it, because they've been told and given their impression not to be concerned about it.
00:41:18.780One of the take-home messages that I try to give to people about this is like, look, whether you believe that cannabis is causing these problems or not, like, let's even forget about that.
00:41:30.200The bottom line is, when you look at large groups of kids, as large a group of kids as you can look at in the U.S., these things are linked.
00:41:38.700So at the very least, they're a risk marker.
00:41:42.300So if you know a teenager, and you're an educator, you're a parent, you're a relative, you're a healthcare provider, and they're using regular cannabis, your antenna needs to go up.
00:41:55.020Your antenna needs to go up and say, wow, actually, this kid is two to four times more likely to have a depressive episode, to have suicidal thoughts.
00:42:03.460They're way more likely to be performing poorly in school, skipping school, having cognitive problems.
00:42:12.500Like, what do I need to do to make sure that they don't have that?
00:42:30.540Like, there's many ways to treat depression.
00:42:32.860Physical activity is a well-documented way to improve depression.
00:42:37.040Exposure to nature is a well-documented way, protective for depression.
00:42:41.660Improving social relationships, connections between family members and peers, very great way to improve depression.
00:42:49.920There are many types of psychotherapy that we use for improving depression.
00:42:55.040There are medications we have for improving depression.
00:42:57.460These are all things that are well-supported in the evidence scientifically, and that we know what the downsides of them are very clearly, and you can make an informed decision around that.
00:43:08.220Cannabis is not a treatment for depression.
00:43:10.400It's not likely to improve your depression anything more than for a short period of time, which from my point of view as a psychiatrist, as a mental health doctor, is not treating your depression.
00:43:18.860Making your symptoms go away briefly is a relief.
00:43:22.200That's not really a treatment that's helpful for you in the long run.
00:43:25.220If someone were to ask you straight up, is cannabis safe?
00:43:34.360Is cannabis safe among over 25-year-olds?
00:43:37.460If the cannabis that you're getting is of good quality, which I think is something that there's still the jury is out on, and you're ingesting it probably as like an, I would say certainly edible would be kind of the safest, and you're using it infrequently, it's probably safe.
00:43:56.840The nuanced parts of it get into frequency of use, you get into the idea of how much you're really using it, because like anything, much like alcohol, the increased use just keeps increasing the negative associations.
00:44:12.420So like a little bit of cannabis, I have this friend who's a pothead who always talks about the idea of like, you've got to find the magic space where you're using just enough where it's improving the quality of your life, but not so much where it's causing problems.
00:44:25.500And I think that that line is not always clear to people.
00:44:28.700If I were to make a general rule, right, if we're going to make a generalization, I think daily cannabis use is like red flaggy, like that's pretty concerning, particularly all day cannabis use.
00:44:40.860So, you know, any of your audience that is waking up and getting high, which is a fairly common thing, that's concerning for a lot of reasons.
00:44:48.860You're always hitting your cannabinoid receptors, you're not really giving them much of a break.
00:44:53.280So daily use is concerning, weekly is kind of on the cusp, monthly, the data looks like there aren't many negative associations with that.
00:45:02.340Well, Ryan, this has been a great conversation.
00:45:03.880Is there some place people can go to learn more about what you're doing, your work?
00:45:07.980You could go to the Columbia Psychiatry website and look up the Sultan Lab, and you can see our past projects, this project, and other projects.
00:45:15.920If you're really nerdy, you can look up the actual paper that we did on this.