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Cannabis, wellness and you

The debut of our Eat Move Think podcast features a panel discussion with three of the world’s experts on marijuana and its health effects

Eat move think podcast with Shaun Francis

Eat Move Think is our new podcast for 2020. Think of it as the audio equivalent of Medcan’s mandate. We’ll explore the topic of wellness, provide guidance on trending topics, and inspire people to improve their lives—to eat better, move better and think better.

Subscribe to Eat Move Think with Shaun Francis on Apple Podcasts, Google Podcasts, Spotify, or your favourite podcast platform. Visit the Eat Move Think website at

Link to podcast transcript

Our first episode explores the topic of cannabis and wellness. We’re in the second year that marijuana has been legal in Canada. But there remains an enormous number of questions. What’s a safe dose? Has CBD oil actually been proven to do anything? And how the heck do you pronounce cannabinoids?

To answer these questions, I gathered together three of the world’s experts for a panel discussion last year at the National Arts Centre in Ottawa. Before an audience of C-suite executives from around the world, I interviewed MDs and scientists who are actually conducting the research at the intersection of human health and marijuana consumption.

Dr. Mark Ware is the chief medical officer of Canopy Growth, the world’s largest cannabis company. James MacKilliop is the co-director of McMaster University’s DeGroote Centre for Medicinal Cannabis Research. And Dr. Rakesh Jetly is the chief psychiatrist for the Canadian Armed Forces and an expert in the therapeutic uses of cannabis for mental health. After the panel discussion, I met in person with Dr. Mark Ware for a follow-up discussion.

“People think you can’t become addicted to cannabis. The reality is, cannabis use disorder is a real psychiatric condition.”

It all makes for a fascinating episode. Following is a transcript of the highlights that my team has edited for clarity and brevity. If you have questions concerning cannabis and wellness, or any other wellness topic, contact me via Twitter @shauncfrancis, LinkedIn, or Instagram @shauncfrancis.—Shaun Francis

Shaun Francis: First of all, what is the state of the evidence with regard to the health effects for cannabis-derived substances like THC or CBD?

Prof. James MacKillop: That’s a great question. The important thing to know is that there are many different sources of evidence and in some ways, the gold standard is always the randomized controlled trial in which you compare a novel medical product to a placebo and you get rid of placebo effects and determine its efficacy. And then at the other end of the spectrum, there are more observational studies,  in which we look at what patients tell us and their practices and whether or not that might give us clues. And there is a lot more evidence at the practice-based evidence end of the spectrum than there is at the RCT end of the spectrum. I don’t want to disparage the state of the evidence, but it is very uneven. And depending on the condition, there may be very little evidence. So for example, in lots of studies, our own and others, we see that many people report using cannabis for anxiety, depression, PTSD. There have been no randomized control trials investigating cannabinoid-related products in those contexts. And so it’s a very mixed bag.

Dr. Rakesh Jetly: Just to add to that, we’ve known for 10, 15, 20 years that there’s benefit. We did a small study right here in Ottawa, looking at nabilone [a man-made form of cannabis] as a treatment for nightmares and PTSD. Across the country, Canadian soldiers are using this synthetic THC for nightmares. The bias for clinicians has been, it’s an excuse to get high. But if you talk to the patients, they’re going to say, you know, when I want to get high—I’ll smoke a joint. When I want a good night’s sleep, I’ll take my nabilone. I think there’s an inherent bias against this substance. That’s probably why we’ve all agreed to this panel, just the idea—Let’s take this into legitimate medical realm.

Shaun: I just received an ad for a CBD infused water for my workout, which basically said, this is what you need to have after your workout. Who’s deciding that an appropriate use of CBD? What’s the dosage? Where’s it coming from? Is there any evidence that says, after my workout, that I should have CBD?

Rakesh: I’ll say no.

James: I think that there’s a lot of interest, right? Kinesiology people I talk to talk about the prospect of CBD and other cannabinoids as post-exercise supplements. Is there evidence? No, there’s no evidence that I’m aware of.

Rakesh: There may be an argument for the anti-inflammatory effect, but a lot of this stuff is not regulated or studied.

Dr. Mark Ware: Yeah, but I think it’s back to this patient-driven idea. I’m prepared to accept that there is an underlying rationale why it could work. And enough people are reporting that they do. We’ve just started a trial with the NHL Alumni Association—hockey players who suffer from concussion related symptoms. And in talking to both active and retired hockey players, you would be astonished at who and how they’re using cannabinoids right now, in the league. The NBA—go Raptors—but you would be astonished if you talk to the professionals, the doctors about the way these athletes are using cannabinoids already. Cannabis is replacing a lot of other drugs, anti-inflammatories, opioids for ongoing pain, for their injuries, for their head injuries. It’s happening already. It’s replacing alcohol. It’s astonishing. So if we don’t listen and capture that, and try to put [that into] evidence, we’re missing something huge

James: The context is so critical, right? Because I think that the reality is that pain management is not a perfect science and the opioid epidemic has not abated in the US. It’s still very much present in Canada also. In the context of sleep—there are not great sleep medicines, and the side effects can be very problematic. So I think we need to be open-minded. Often the role of cannabis in these contexts is where medicine is not prevailing, or not delivering what we need. We need better treatments. If something is strong enough to help you, it’s almost certainly strong enough to hurt you. So you need to be mindful that there’s going to be upsides and downsides. The critical thing is to be clear-eyed about where we are in this very rapidly changing world, and mindful that although there is great potential for benefit, there may be some harms that come along that we want to know about sooner rather than later.

Shaun: So just building on that, what are the known risks for either THC or CBD?

Rakesh: THC is supposedly the most psychoactive. There is a risk of psychosis—not being in touch with reality. There’s the long-term risk of heavy users of actual dependence in the addiction sense.

James: Unfortunately, people often think that you can’t become addicted to cannabis or that you can’t overdose on cannabis. And the reality is, cannabis use disorder is a real psychiatric condition. It doesn’t happen to most people. It happens to a small minority of individuals who use cannabis. It’s in general about proportionately the same as alcohol. Many people use alcohol, a small number of people develop an alcohol use disorder. That doesn’t mean that there’s no such thing as alcoholism. It just means that it’s part of the risk profile when it comes to overdose. One of the great benefits of cannabis is that there’s no toxic level. Technically, we call that the LD50—the dose at which 50% of people would die from a dose of a drug. And the LD50 for cannabis is so high as to be biologically implausible that you can consume that much. But you can over consume, you can experience delirium, psychosis, significant impairment. Especially when it comes to the edible products that can be consumed very easily and will not result in any immediately detectable effects. There is higher risk for subsequent significant impairment and overdose, because small amounts of THC go a long way in the body. Those are things that people need to be aware of.

“What we’re doing with cannabis is rethinking a drug that for decades was illegal, and now we’re beginning to talk about it as potentially having medical value.”

Mark: It depends on when you use cannabis. So what age of life you are. There are different risks if you’re young—under the age of 18. Other risks as in the older population. I think we’re focusing a lot on the young. We’re not thinking about the older person who’s 65, 70 who might try a THC lozenge for the first time. So there’s when do you start using cannabis? What products are you using? High THC products are clearly associated with more risk than the low THC products. So teaching people to use lower strength—take the decaf coffee instead of the high potency coffee, just to reduce risk. And then the mode of administration [matters]. Smoking is different from oral. Vaping is different. When you use it, how much you use, how you use—all of those affect the risk profile.

Shaun then opens things up to the audience, and a woman asked, “Marijuana is legal. And then recently Denver, Colorado decriminalized psychedelic mushrooms—magic mushrooms. Where does this end?”

Rakesh: I don’t know where it’s going to end. The FDA has just declared MDMA-assisted psychotherapy, which is ecstasy by the street name, as a breakthrough therapy for PTSD. The data, the studies, are actually compelling. They’re almost hard to believe. Like, 80, 90% cure rates. This is giving people a small controlled amount of MDMA, to maybe reduce some of the inhibitions. Maybe we’ll talk about things that aren’t able to talk about in traditional therapy. Then they have an eight-hour psychotherapy session with two therapists. It’s the weirdest thing in the world. But it seems to work.

So I think, you know, for us as scientists, let’s look at the molecules. Let’s try and look at safety, efficacy, control, ethics review boards, you have to submit and back and forth questions to make sure things are safe, but I don’t think there is a limit, because as long as we have receptors in the body, that can be affected by things. There’s a potential positive and benefit for most things.

Mark: What we’re doing with cannabis is rethinking a drug that for decades was illegal, harmful, and now we’re beginning to talk about it as potentially having medical value. I think the same thing is happening with psychedelics. You’ve seen this with psilocybin. We’ve seen this with LSD, with ketamine, with MDMA. And I think it’s a paradigm shift. I think we’ve we have to look back at why these drugs were made illegal, why we think what we think about them as harmful drugs of abuse. And I think society is now beginning to rethink these. Perhaps there is a need for new pharmaceuticals. Perhaps there is a desperate need for new drugs that are replacing some of the synthetic molecules that have emerged in the last 40 years. But I think we’re going through a very important time where we’re rethinking many of these substances. And a lot of our societal prejudices and stigmas and biases are being brought to the front to think okay, when you say mushrooms, I think psilocybin, and I see treatment trials—for depression, and PTSD and smoking cessation—that are remarkable. So just thinking of marijuana as cannabinoids, thinking of mushrooms as psilocybin, this is the rethinking that’s taking place and I think it’s potentially very, very exciting neuroscience.

Shaun: So we’re out of time. But can I ask just one question that maybe hasn’t been asked? What would you say if someone wants to experiment for sleep or back pain—like should they just go down to the new marijuana shop and talk to the clerk?

Mark: That’s a dangerous question to try and answer—what should you do? I think it depends on why you want to try cannabis fundamentally. Rakesh pointed to this slippery line between what’s recreational, what’s medical. I think of it as a kind of spectrum really, when people might be medical one day and recreational on a Friday night. But talk to your physician. I think that’s the first thing if it’s medical. If it’s recreational—you just want to have a good time? Go talk to the bud tender and say I’m going to watch a movie and they’ll be like, is it a comedy? Are you watching a horror movie? They’ll tell you what strain you want, down to, are you watching basketball or hockey.


The actual podcast recording also features Shaun interviewing Dr. Mark Ware one-on-one and discussing at greater depth the risks of harm to young people as well as the intersection of psychedelics and wellness. Thanks to Dr. Mark Ware, Dr. Rakesh Jetly, Professor James MacKillop and the CEO organization that hosted the panel discussion at Ottawa’s National Arts Centre.


Shaun Francis is Medcan’s CEO and chair. Follow him on Twitter @shauncfrancis. Connect with him on LinkedIn. And follow him on Instagram @shauncfrancis

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