Front Burner - How much booze is too much booze?

Episode Date: January 20, 2023

According to the Canadian Centre on Substance Use and Addiction, people should limit their alcohol consumption to just two drinks per week to avoid certain cancers and other health issues. The new health guidelines significantly reduce the number of drinks considered risky — the previous recommendation capped weekly consumption at 15 drinks for men and 10 drinks for women. On today’s episode, Tim Naimi, director of the Canadian Institute For Substance Use Research at the University of Victoria and a member of the scientific advisory panel that contributed to the new guidelines, tells us what’s behind the changes.

In the Dragon's Den, a simple pitch can lead to a life-changing connection. Watch new episodes of Dragon's Den free on CBC Gem. Brought to you in part by National Angel Capital Organization, empowering Canada's entrepreneurs through angel investment and industry connections. This is a CBC Podcast. Hi, I'm Jamie Poisson. No more than two drinks per week. That's a bit tight.

That's horrible. I mean, I think so. I don't know. I can have two drinks in like an hour. Easy. I think I'm in a lot of trouble. Two drinks per week. According to new Canadian guidelines, anything above that increases your risk for several cancers.

And anything above seven increases your risk for heart disease and stroke. Oh, God. Like 25 to 30. I'm, what, 28 over? I would definitely drink more than two. Would you ever give it up? No. I'm Australian.

Part of your culture. It is, pretty much. I can't take that. Yeah, I think I drink every day. We hear you. We hear you. So today, we're going to look at the science behind these new guidelines to try to give you a better sense of how to understand them and how to navigate them. Tim Namy is part of the scientific advisory panel that contributed to the new guidelines. He is also director of the Canadian Institute for Substance Use Research at the University of Victoria. Hi, Tim. Thanks so much for coming on to FrontBurner.

Oh, thanks, Jamie, for having me. I'm excited. So I wonder if we could start here. The story used to be, right, that the occasional drink actually had health benefits. There was this idea that wine, red wine in particular, could actually improve your heart. Now it's been all but confirmed. The wine apparently affects the platelets, the smallest of the blood cells. The wine has a flushing effect. It removes platelets from the artery wall. And so where did that idea come from? Well, that idea, which as you mentioned,

has kind of fallen a little bit by the wayside scientifically. But anyways, that idea came from the French. The farmers have been eating this for years. They've been eating a very high-fat diet, it seems, and yet they don't get heart disease. If we took the same diet and put it into an American, you know, we would all be suffering from carnivores at an early age. There's something about the French that seems to be protecting them. You know, the so-called French paradox, this idea that people in France who tend to drink wine tend to live long.

If you go to the north in France, they're using more butter and cream. And yet the rates are still lower there. Now, why are the rates in Lille lower than in Boston? Well, my explanation is, of course, the consumption of alcohol. But the thing is, one of the problems with studies of alcohol is that often people who drink sort of moderately over a long period of time, those are kind of a select group of people. So, you know, for example, somebody who is in Canada and has been drinking for many years and they're, you know, they haven't died from alcohol or they haven't become an alcoholic or quit because of a health-related problem from drinking. They're kind of a select group. And that created this impression. But I

would say, Jamie, the way I would frame that is that even from based on the older studies, the risk of alcohol-related problems starts to increase at very low levels of consumption. So even from that older science, the idea that less is better was still there. So anything over even from the older stuff, about half a drink a day, the risk started to increase. The flavor of ours is a little bit more sort of, let's say, sober from a scientific perspective, but in general, to the extent that people are willing or able to drink a bit less is going to be good for their health. That hasn't really changed.

It's so interesting, though, because I feel like I remember headlines that said research backed up, you know, a glass of wine a day. That was good for your heart. This is news that I just love to keep reporting on. Wine is good for your health. Researchers have long espoused the health benefits of red wine. Daily glass of red wine may improve heart health. Was there ever research that backed that up? Yeah, so you saw a lot of those headlines, but you see an equal number.

Again, the science has been a bit contentious, but it's mainly at the very lowest levels of consumption. Like, is this low amount possibly beneficial or sort of neutral or harmful? But again, the main message would be that these are for consumption levels at less than a drink per day on average. And again, the science has been entirely consistent that once you go like above a drink a day on average, that the risk is increasing. So the new guidance, you know, is illustrating that the risks begin at lower levels than previously appreciated, but the idea is generally the same. So the new guidelines say if I drink more than two drinks a week, I start to move into a moderate risk zone for several types of cancer.

And how do we know the number is as low as two? Sure. So basically, all the guidance is saying is that there's no increased risk at all for up to two drinks a week. Again, this guidance is also different that we're not kind of telling people to get to one number. We're just trying to improve information and hope that people will be interested in their health. So basically, when you put together the risks from all the different conditions that can be caused by alcohol, you kind of put all of those risks together, you find that there's essentially no increase in risk with one or two drinks per week. And then the risk slowly starts

to increase above that. So that up to six drinks per week is considered sort of moderate. And that level of consumption for an average person is related to less than a 1 in 100 risk of developing a problem. And then above 6, so starting at 7, the risks are higher than 1 in 100 and climb with the more you drink. And when we talk about problems, what kind of problems are we talking about here? Yeah. So those would be things like cancers, like liver problems, like injuries and accidents, those sorts of problems. Alcohol, you know, as you might guess, affects a number of different health systems that can affect, especially at higher levels of consumption, the brain. All the different forms of heart disease at higher levels of consumption are made worse. The risk of cancer, the increased risk starts

with any consumption. So those are the main ones. And then a lot of the gastro, the stomach and intestine problems as well. You mentioned accidents. Are things like drunk driving accidents included in that risk ratio that you mentioned, the 1 in 100? Well, for things that relate to drunk driving or most of the, we call them injuries or the violence-related ones, the important factor there is what we call per-occasion consumption. So it's not actually as important how much you consume in a week, but it's how much you consume on any drinking occasion. There's something that's called binge drinking. That's a standard thing in public health where men who consume five or more drinks or women who consume four or more drinks on a single

occasion, they pretty much invariably end up acutely impaired from alcohol. And that's a very common and risky pattern of consumption. But the question is drinks. So that's 12 ounces of beer, five ounces of wine, or an ounce and a half of hard alcohol counts as one drink. So for example, you have three beers at a ball game and two glasses of wine and you're binge drinking. Most people don't realize how little it takes in a sense, right, to be classified that way. And actually, in terms of the risk of accidents or interpersonal like violence, that sort of thing, the risk goes up starting at above two drinks a day. So for people who are interested in avoiding that sort of problem or causing those sorts of problems, ideally people would limit consumption to a

couple of drinks on any drinking occasion. When you talk about cancers, what kind of cancers are we talking about here? Yeah. So there's seven cancers that are considered definitely causally related to alcohol. I should take a step back and mention that alcohol is considered a class one carcinogen by the World Health Organization. A class one carcinogen means that there's excellent evidence from human studies, like human epidemiological studies, that you can reproduce the same thing in animal testing, and that there's also that the mechanisms of why it causes cancer has been worked out like in the laboratory at the cellular level. So alcohol is class 1 carcinogen, the highest level.

Other class 1 carcinogens, for example, include tobacco smoke and benzene. The cancers that specifically alcohol can contribute to or can cause are colon and rectum cancer, breast cancer, liver cancer, and then all the cancers of the mouth, the throat, the esophagus. So a lot of the gastrointestinal cancers, liver, breast, colon and rectum. And then there's a strong association, though it's not as breast, colon and rectum. And then there's a strong association, though it's not as clear-cut at the present time,

with stomach cancers, pancreatic cancers, and prostate cancer. What do you think about two drinks per week? I think it's a good idea. I think it's tough to do that, but it's probably healthy. I mean, I don't really drink much anymore, but I feel like in general, I don't know, it's spread all throughout Canada. There's really boring places where there's not much to do other than drink. That was kind of mean.

I think it's a bit ridiculous. Based off of sort of what rubric are we measuring health, we're surrounded by things that are killing us constantly. Well, they allow two glasses on the ferry and they sell it to you. And that's only an hour sailing, so... I don't know. I feel like anyone who drinks, if you're drinking two drinks per week, what's the point? But I don't know. I feel like anyone who drinks, if you're drinking two drinks per week, what's the point? But I don't know.

I feel like they super low-balled it to a point where it's like unrealistic to where I just kind of forgot about it. In the Dragon's Den, a simple pitch can lead to a life-changing connection. Watch new episodes of Dragon's Den free on CBC Gem. Brought to you in part by National Angel Capital Organization. Empowering Canada's entrepreneurs through angel investment and industry connections. Hi, it's Ramit Sethi here. You may have seen my money show on Netflix. I've been talking about money for 20 years. through Angel Investment and Industry Connections. That's not a typo. 50%. That's because money is confusing. In my new book and podcast, Money for Couples, I help you and your partner create a financial vision together. To listen to this podcast, just search for Money for Couples. kind of wade through this research. So I understand this research looked at hundreds of studies, and they looked at people who have conditions who were also drinkers. But here's my question.

If you're asking and looking at drinking, is it possible that you're ignoring other things? So, for example, a lot of people who drink and have these conditions, maybe they drank in really smoky bars. And that's also why they might have, you know, if we're just looking at like a percentage of increase of risk here, you know? Yep. No, that's a great question. All of these studies to be even included into the groupings and to be, you know, sort of contribute. They have to meet some minimum scientific requirements. And like, for example, in any study of alcohol, you have to statistically account for the likelihood that somebody is a smoker or not, because you're absolutely right. A lot of people who drink alcohol are a bit more likely to smoke. And we know smoking is a big cause of cancer too, right?

So we don't want to, you know, contaminate, you know, the effect of alcohol with smoking. So most studies control for smoking. They control for age. They control for different other individual factors that could kind of, what we say, obscure the actual relationship with alcohol. That's the intent, right? But it's not always possible to control for everything. And some of these difficulties with the methods is why over the past 10 or 20 years,

the conclusions about the health effects of alcohol have changed. And that's because people are more aware of and better able to account for these factors that can kind of screw up the results, if you want to use a scientific term. Yeah. I guess, what about just being around secondhand smoke? Would it account for stuff like that? I mean, I just, you know, I went to McGill during my university years, spent a lot of time in bars that were filled with smoke, right? Like, I wasn't a smoker, but... The other thing is, it's interesting, you mentioned smoking. I think one thing we know that in Canada, for example, You mentioned smoking. I think one thing we know that in Canada, for example, when it comes to the risk of cancer, most Canadians are aware that cigarette smoking increases your risk of a number

of types of cancer. But probably less than a quarter of Canadians are aware about the relationship between alcohol and cancer. So that's kind of an interesting thing. One way that you can kind of think about it is that some people have made some sort of crude estimates that, you know, a standard drink of alcohol, that being, you know, sort of a can of beer, standard strength beer, or a glass of wine, or a shot of spirits, that's sort of equivalent to about one or maybe a little bit more than one cigarette in terms of the cancer risk. The other thing is, Jamie, I don't want, you know, for people who drink alcohol, you know, particularly small amounts of alcohol, you know, I don't want them saying that like,

just because you have a drink of alcohol, you're going to get cancer. So you know what I'm saying? I want to be fair to the information, but let's use an example like breast cancer. So alcohol is an important risk factor for breast cancer. And just to put it into a bit of a context for a woman, for each additional drink that one consumes per day on average, the risk of breast cancer is increased probably about sort of 8 to 10 percent. That gives you kind of a sense. Yeah. Alcohol is an important cancer risk. There are lots of other

ones. Tobacco, as you mentioned, being overweight is also a risk factor. And then there's other environmental ones, smoke and other things. This idea that a drink per day on average increases your risk of breast cancer by 8%, there still has to be a baseline risk of breast cancer, right? Exactly. It increases it by, let's say, 8% or 9% relative to your baseline risk. Right. So maybe you had a 0.002% chance of getting breast cancer, and now you have a, sorry, math is not my strong suit, a 0.004% chance of getting breast cancer. Let's say very, very roughly that 1 in 10 or 1 in 12 women, I'm just pulling this off the top of my head, will get breast cancer in their lifetime.

When you multiply that, maybe like each additional drink increases your risk of breast cancer by like 1% in an absolute fashion. So we're getting into the weeds of statistics, but I think it's really this whole idea of how you kind of communicate risk in a way that's understandable is it's really challenging. And so I'm sort of glad that you're asking these questions. The other question I wanted to ask you, you know, we've been talking about cancer a lot, but also when we talk about alcohol, the guidelines say if I drink seven or more drinks per week, I guess I start to move into a higher risk for heart disease and stroke. And I just, I wonder if you can explain to me why, what's actually happening in my body there. There's several different things going on.

One of them is that when you drink more alcohol, it actually raises blood pressure. So for people who are drinking a lot, their blood pressure may start to go up. And then there's other inflammatory things that are sort of floating around in the blood that go up with increased consumption. Okay. And same thing that we were talking about before, right? Like you have to have a baseline risk for this as well. That would... Right. Yeah. If I could just bridge to one thing that's really important is these are guidelines for the general public. So for any individual person, there's obviously

tremendous variability, like you're all over the back, but the risk for one person, you know, is going to be much higher or lower than the risk for another person, right? So there are a lot of reasons people drink alcohol and it's a legal substance and it's enjoyed by many people. When you boil it all down, like if you're interested in health and like less is better. But if people choose not to drink less or whatever, that's that's that's fine. But it's just good for folks to sort of have a sense of sense of that. Right. Because you're saying our whole lives are about navigating risk as well.

Because you're saying our whole lives are about navigating risk as well, right? For example, we just did this show about gas stoves and new research that shows that gas stoves are linked to a 12% increase in childhood asthma. And, you know, I'm just going to guess that not everybody listening to the podcast went out and bought an induction stove the next day. But I think it's possible people started thinking about their next purchase for their gas stove. And one thing I did want to ask you about is I was reading some research that said that researchers believe alcohol is actually damaging our DNA or changing our DNA, which is something I hadn't heard before.

And I wonder if you could just take me through that. Alcohol does sort of denatures DNA, which means it just screws up with the way it assorts and the way that it replicates. And certain tissues are very vulnerable to that. So as a version of that is like alcohol causes birth defects. It basically can interfere with replication of cells and that sort of thing.

And it's for this reason that alcohol tends to, you know, affect a lot of organ systems. You know, other than sort of kidneys and lungs directly, you know, alcohol, especially at high levels, can affect brain tissue, affect gastrointestinal tract, the heart, the liver, the immune system. And that's because it's a small molecule. It gets everywhere. And, you know, you a small molecule. It gets everywhere. And, you know, you can preserve things in alcohol. You can basically, yeah, it can be very toxic at the cellular level and particularly, well, low amounts over time. And then also, you know, when people get, you know, very drunk or intoxicated, there can even

be acute effects on the cell. Okay. And I'm going to guess that this is probably the big reason why no alcohol is recommended during pregnancy. Correct. Alcohol is the leading preventable cause of birth defects and of developmental neurological problems. So yeah, that's a really important one. The new guidelines I found interesting. They're the same for men and women, which has not always been the case, right? I thought women were more at risk from drinking alcohol. And so why?

Yeah, you ask a great question. Well, the reason is that the risk for men and women at up to about 10 drinks per week are really, really similar. Then once you go at higher levels of consumption, about say 10 drinks per week or above about a drink and a half per day or two drinks per day, then you see the risk start to diverge. So as you say that on a per drink basis, the risk for women become higher than for men. But for a guideline, particularly since they were so similar and that's just to be simple, it basically the risks were almost identical. And so that's why the recommendation is the same for men and women. But before we leave, I can't let men off the hook here because a lot of people always seem to stress the risk among women. But the key point also to remember, since you're very good

statistically, Jamie, is that because more men in the Canadian population drink, and because they drink a lot more than women in general, even relative to their larger body size, about three quarters of all deaths from alcohol in Canada occur among men. And men also cause the most harms and deaths for the secondhand effects of alcohol. Right, domestic violence. Domestic violence, I would imagine. Domestic violence, right. So yes, women on a per drink basis at higher levels of consumption are at higher risk. But overall, unfortunately, alcohol and men should remain an important focus. We heard at the top of the show, people essentially balking at these new guidelines, right? Like a lot of people are like, I cannot drink two drinks a week.

I currently drink 14 drinks a week. And so what would you say to those people? Absolutely. So we're stuck in this situation where we know alcohol is a legal product. It's popular. We get it. We think the public has the right to know what the risks are, but we also want to engage people and we do understand the reality of the situation.

So what we want to do is speak to everyone and particularly people who are drinking more, right? So if somebody is drinking six drinks a day on average, if they can cut down to three drinks a day on average, that's fantastic. Or the person who's drinking, I don't know what your example was, but if they can go from- 14 drinks to 10? Yeah, whatever it is down to a little bit less, that's wonderful. And that's the main message that we're getting across is not just that you have to get to a number, but to think about what you'd like in terms of your risk and to the extent people concerned about their health and well-being. This idea that less is more when it comes to life expectancy and possibly quality of life.

Okay. Thank you so much for this, Tim. It was really interesting talking to you and also digging beneath these headlines a little bit. So thank you. Okay. Super for this, Tim. It was really interesting talking to you and also digging beneath these headlines a little bit. So thank you. Okay, super. Thanks, Jamie. All right, that's all for this week. Front Burner was produced this week by Shannon Higgins, Lauren Donnelly, Derek Vanderwyk, Rafferty Baker, Jodi Martinson, and Allie Janes. Derek Vanderwyk, Rafferty Baker, Jodi Martinson, and Allie Janes. Our intern is Jack Wanen. Our sound design was by Sam McNulty and Mackenzie Cameron.

Our music is by Joseph Chavison. Our executive producer is Nick McCabe-Locos, and I'm Jamie Poisson. Thanks so much for listening. We, go to cbc.ca slash podcasts.