Using Cannabis Doubles Cancer Risk, or Does It?

Understanding risk and effect size in research.

Does cannabis use really double the risk of cancer? I break down what the research actually says, the importance of examining effect size, and how statements based on research findings can be misleading.

In This Episode

Intro … 00:00:44
Controlling for Variables … 00:02:14
How Cannabis is Used … 00:08:16
More Confounding Factors … 00:10:14
Episode Wrap-Up … 00:13:33

Using Cannabis Doubles Cancer Risk, or Does It? - RuscioRadio FMF

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Welcome back to another episode of Dr. Ruscio radio. This is Dr. Ruscio actually coming to you on a Saturday, which I rarely actually podcast on Saturdays. However, I was just going through some information on cannabis and cancer, and it is such a choice example of how we have to not only describe to people, risks associated with certain behaviors, but we have to quantify the level of risk. When you tell someone behavior X, in this case, cannabis, may increase male risk of testicular cancer, but you don’t quantify the magnitude of that risk, you can lead people into a position of unnecessary concern. And rightfully so. This is why it’s so crucial. Any time we’re discussing risk, we as best we’re able to, quantify the degree of risk. So in this case, I was having a conversation with a colleague of mine in Urology, and the topic of cannabis use came up and he remarked that there have been meta-analyses, finding an association between cannabis use and increased risk of testicular cancer.

➕ Full Podcast Transcript

Intro:

Welcome to Dr. Ruscio radio, providing practical and science-based solutions to feeling your best. To stay up to date on the latest topics as well as all of our prior episodes, make sure to subscribe in your podcast player. For weekly updates visit DrRuscio.com. The following discussion is for educational purposes only and is not intended to diagnose or treat any disease. Please do not apply any of this information without first speaking with your doctor. Now let’s head to the show.

DrMR:

Welcome back to another episode of Dr. Ruscio radio. This is Dr. Ruscio actually coming to you on a Saturday, which I rarely actually podcast on Saturdays. However, I was just going through some information on cannabis and cancer, and it is such a choice example of how we have to not only describe to people, risks associated with certain behaviors, but we have to quantify the level of risk. When you tell someone behavior X, in this case, cannabis, may increase male risk of testicular cancer, but you don’t quantify the magnitude of that risk, you can lead people into a position of unnecessary concern. And rightfully so. This is why it’s so crucial. Any time we’re discussing risk, we as best we’re able to, quantify the degree of risk. So in this case, I was having a conversation with a colleague of mine in Urology, and the topic of cannabis use came up and he remarked that there have been meta-analyses, finding an association between cannabis use and increased risk of testicular cancer.

Controlling for Variables

DrMR:

Now, my follow-up was knowing that there is often this unhealthy user effect, have the confounding variables been controlled for? He didn’t believe so. So I decided to look into this a little more closely. If there is something there, this is something I would want to know about and I’d want to share with our audience. We have showcased the benefits of cannabis use, but I’m always trying to be as even-handed and objective in my analysis as possible. So this potentially could be something that needed to be shared with the audience to give people a complete understanding regarding the pros and cons of the use of cannabis. So as we look into this, we find that there is a more recent meta-analysis that did control for confounding variables. I’m going to come at the controlling for confounding variables two times.

DrMR:

Once from kind of a high level, that there was an attempt to control for confounding variables. This more recent meta-analysis agrees with the older meta-analysis that was referenced by my colleague. The colleague I’m referring to is Dr. Paul Turek, who has done some very exciting work in the area of male urological health and male infertility. So certainly someone who is well in the know. He had a blog post on this, I believe from 2019. I’ll see if I can grab the link for that and include it in the notes. So in his blog post from about a year or so, I guess now two years ago, they were quoting an older meta-analysis. A more recent meta-analysis did control for these confounding variables. So after controlling for the confounding variables such as maybe the marijuana users are also eating a bunch of junk food, smoking, tobacco, drinking a whole bunch.

DrMR:

You kind of have this stereotypical “stoner” that we could kind of straw man. Once that has been controlled for the association still persists. Okay. So now this finding has my attention, a little bit more firmly gripped. So the next thing that we want to examine here is the effect size. The effect size is just the magnitude of the effect. Here’s where numbers can be confusing if they’re not unpacked with the due context. There is a doubling of risk for testicular cancer when men habitually use cannabis. Wow, that grabs my attention even more. But here is the important contextual bit to factor in. This leads from a change or a risk of 1 in 250 to a doubling, 2 in 250. Stated another way, a 0.004% risk to a 0.008% risk. So there is a risk. There is a doubling. However, it seems to be human nature, especially if haven’t spent much time in health science/medical literature, to understand that a doubling doesn’t always have the impact we would think.

DrMR:

We’re used to associating doubling to a high magnitude impact. However, when we’re talking about a 1 in 250 doubling to a 2 in 250 risk, that is, in my opinion, more of a clinically insignificant risk change. So 0.004 to 0.008, doesn’t seem to be enough of a risk. Now this is my opinion. I don’t know that there’s any absolute agreement on what effect size is considered one for which an individual should change their behavior. This is something that needs to be performed on an individual basis, depending on how much risk you’re willing to tolerate. In this case, for me, anyway, it seems that the benefits of cannabis use far outweigh the potential risks.

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How Cannabis is Used

DrMR:

Now, I should also clarify that I do feel it depends on how you’re using cannabis. This is my position, not necessarily what I can point to an RCT to substantiate. This is just how do I take this information and use it to interface with the world in the most successful way possible? I don’t feel to be a good practice to use cannabis, to sit on the couch, watch movies and binge on junk food. Now, if someone is quite stressed and cannabis use helps them to relax, then I leave the door open for that utility there. I don’t think it’s a good long-term solution because you don’t want to escape to something like cannabis as the only way of dealing with your life. As something that’s used in moderation periodically for someone who’s really stressed or has a time hard time sleeping, or has inflammation that this helps them with, I see the potential therapeutic benefit there.

DrMR:

As we’ve discussed in the podcast, I believe it was Jordan Tishler, where we really hit this. It can also be helpful in spawning increased intimacy between couples. I found it can be very helpful when paired with cardiovascular or really with any exercise, but my preference is cardiovascular exercise and then going in the sauna. It allows for perspective shifting and kind of meditation and enhancing effect. So for me, it almost has been something that’s infused and potentiated this almost like a spiritual practice. So depending on how you use it, I think it can be more or less justifiable. Coming back to the issue of confounders, and this is where my clarity starts to get a little bit hazy based upon the literature. There are a few things that we’re looking further into, but the controlling for the confounders while present, seems to be imperfect.

More Confounding Factors

DrMR:

At least as I’m able to understand it, there is a challenge in some of the research studies where there wasn’t a good delineation between those who were marijuana only smokers as compared to those who smoke marijuana and things like tobacco. Also quantification, meaning how much did these users use, is also something that seems to have been poorly tracked in the research studies. This is such an important issue in the sense that if someone wanted to create kind of a straw man avatar against cannabis use these data points could be used in a very misleading way. I think unfortunately this happens more often than it should in healthcare. I’m not sure exactly why. There are probably a few different underlying causes, some malicious and some benevolent. Picture this narrative with only being told that risk for cancer doubles when using cannabis. You could even spin this more and say, meta-analyses have found this. This is why it’s so important to also mention the effect size. It’s something that I’ve become increasingly aware of.

RuscioResources:

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Episode Wrap-Up

DrMR:

So in any case, I just want to share these few thoughts because the more I get down into the details, I realize how crucially important it is when we’re having discussions regarding healthcare. We have to do the best that we can to check the effect size, check for confounding variables and try to give people an understanding of how much a given behavior impacts their risk. So, hopefully this is helpful and it’s really a principle that can be applied to any facet of health, healthcare, medical research, to try to make sure that we’re not misrepresenting data. So there you have it folks, just a few musings on effect size here on a Saturday morning. Okay. Hope this helps. Talk to you next time.

Outro:

Thank you for listening to Dr. Ruscio radio today. Check us out on iTunes and leave a review. Visit Dr. Ruscio.com to ask a question for an upcoming podcast, post comments for today’s show, and sign up to receive weekly updates.

➕ Resources & Links

Sponsored Resources

DrMR: Is your gut not as healthy as it could be? Thankfully, there are many options out there that can help you. One that can can lead to rapid reduction of symptoms, inflammation, and imbalances is an elemental diet. I’m very proud to say that we’ve developed a line of elemental diets that are accessible and also do not require a doctor’s recommendation. We have our original vanilla and chocolate as well as the only low carb and the only whey free versions that do not require a doctor’s note. We are about to release a low carb vanilla, and a whey free peach.

Using Cannabis Doubles Cancer Risk, or Does It? - auto
Using Cannabis Doubles Cancer Risk, or Does It? - auto
Using Cannabis Doubles Cancer Risk, or Does It? - auto

If you head over to our store and use code, GetElementalHeal, all one word, you will receive 15% off your first order. Head over there and check it out. Hopefully you like many others will experience the quick resolution and improvement in your symptoms by using a simple intervention of elemental dieting.


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