Ep. 69: Are We Too Clean? with Professor Brett Finlay

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Here’s a little known secret: Germs are good for you. Every single one of us has a complex and unique microbiome that lives on us, and in us. It’s made up of microbes — things like bacteria and protozoa. Our microbiome plays a huge role in our health and, as microbiologist and University of British Columbia professor Brett Finlay has discovered, it is even connected to non-communicable illnesses, like asthma or cardiovascular disease. That’s why pandemic-bred habits like cleaning surfaces with antibacterial wipes, or chronic use of hand sanitizer, can be so problematic: They kill bad germs, and good ones, too. Which prompts the question: Is our COVID-caused mania for germ killing messing up our microbiome? In conversation with Medcan chief medical officer Dr. Peter Nord, Prof. Finlay answers these questions — and more.

LINKS

You can find Brett Finlay on Twitter. 

Read the paper he lead-authored for PNAS on the hygiene hypothesis, COVID-19 and its impact on the human microbiome here. 

He’s also written two books: The Whole-Body Microbiome, co-written with gerontologist (and his daughter) Jessica M. Finlay, and Let Them Eat Dirt. 

Watch this interview with Finlay, in which he discusses building a healthy gut microbiome.

Check out “Can We Learn to Live with Germs Again?,” a New York Times feature on the human microbiome and the need to get comfortable with being exposed to bacteria. 

INSIGHTS

Our path to slowly damaging our microbiomes started 125 years ago, back when Robert Koch and Louis Pasteur made their seminal discoveries (that microbes caused disease, and that killing microbes could kill disease, respectively). These discoveries lead to sanitation, hygiene, antibiotics and vaccines — which, to be clear, are all good things. But what scientists eventually realized is that when we try to kill microbes, we kill all of them, even the ones that make our microbiomes healthy. This led to David Strachan’s hygiene hypothesis, which essentially argues that we live too cleanly and that the rise of things like allergies and asthma are linked to our reduced exposure to germs. [Time code: 3:25]

According to Finlay, newer research has found that microbes actually have an influence over non-communicable illnesses, like cardiovascular disease, too. For example, people who are born via C-section — and are therefore not exposed to the same microbes associated with vaginal delivery — have a 25 percent higher chance of getting asthma; they also have a 30 percent higher chance of being obese. “There’s actually quite a tight link,” he says. “It’s a fascinating thinking experiment.” Some research even indicates that your environment and proximity to people plays a part in your microbial health — that’s why spousal rates of inflammatory bowel disease is actually pretty high, even though you are, of course, not related to your partner. In other words? Be careful who you’re kissing.  [Time code: 8:29] 

COVID has changed all of us — our microbiomes included. We shy away from close contact to people, we’ve been (necessarily) wearing PPE for a long time now and we’ve mostly been inside for the past year, meaning we’ve been exposed to far less germs than we normally would have been. Finlay worries that this will have the biggest impact on children and the elderly, when microbes have the largest effects on our overall health, which could lead to higher rates of things like asthma and obesity in the coming years.  [Time code: 15:07]

We’ve all been a bit more hyper-aware of our hygiene during the pandemic, but Finlay cautions against letting our changed behaviours become permanent habits. Of course, we should all continue to follow public guidelines, socially distance and wear PPE as long as the risk of COVID remains high. But if you’re still wiping down your groceries or Amazon packages, it’s long past time to stop that — disinfectant wipes don’t stop the spread of COVID, anyway. And during non-pandemic times, Finlay’s hand-washing rule is simple: “I generally say soap and water before dinner, but lay off the hand sanitizer. All it does is kill the good microbes on your skin.”  [Time code: 21:05]

So what can we do to fix our microbiomes? Luckily, there are a few things. First, is eating well: Finlay recommends a Mediterranean-style diet that’s full of fruits, vegetables and legumes, and low on dairy, fat and sugar. Next, is getting outside — don’t be afraid to let your kids roll around in the grass, or get a little dirt under your fingernails. You probably won’t be surprised to learn that exercising has a beneficial effect too, as it can increase your anti-inflammatory microbes. And you need to lower your stress levels, too, as stress can actually cause an inflammatory response in your microbes that can lead to other diseases. “Post-COVID, chill out,” Finlay says. “Just sit back, play with the kids, go outside and eat well, and maybe you’ll add a decade to your life.”  [Time code: 22:46]

And if you take probiotics — or you’re tempted to start — know that they likely won’t have a big overall effect on you microbiome. Finlay compares them to trying to find a new pair of running shoes: You walk into a store and are bombarded by options. You don’t just grab the cheapest pair and then walk out. Because probiotics are not regulated, companies tend to be looser about the claims they’re making. “We just have to realize we’ve impacted our microbes and realize that there are things we can do to help them, because they’re our friends and they’re going to help us down the line,” Finlay says. [Time code: 23:54]

Are We Too Clean? with Professor Brett Finlay final web transcript

Are We Too Clean? with Professor Brett Finlay final web transcript

[00:00:10.09]

Christopher Shulgan: Welcome to the 69th episode of Eat Move Think. I'm executive producer Christopher Shulgan.

Christopher Shulgan: Ever hear of the hygiene hypothesis? Today, it's taken to mean the theory that many of the lifestyle choices that are prevalent in wealthy nations are messing up what's known as our microbiome—the millions of germs that live on us, and in us, in our digestive tract, on our skin. The problems with the microbiome are thought to have triggered rising rates of chronic diseases, including obesity, diabetes, asthma, and such auto-immune diseases as psoriasis, hay fever and irritable bowel syndrome.

[00:00:45.13]

Christopher Shulgan: Contributing to problems with the microbiome are things like city living, diets full of processed foods, smaller families, and a tendency not to have pets, too much antibiotic use, and most intriguingly to many, the obsession we tend to have about hygiene in our home and on our bodies. Essentially, the hygiene hypothesis suggests that we're too clean.

Christopher Shulgan: It was first suggested by a British epidemiologist back in 1989, and it took until the mid-2010s to really percolate through society. One of the best-known experts in the theory is Brett Finlay, a microbiology professor at the University of British Columbia. He called one of his books Let Them Eat Dirt. And thanks to the advocacy of Finlay and people like him, people started to understand that cleaning products that killed 99.9 percent of all germs, maybe weren't such a great idea to use all over the place.

Christopher Shulgan: Then the pandemic happened, and for the last 14 months we forgot all about the hygiene hypothesis. Now, in a widely-cited academic article from earlier this year, as well as in a Sunday New York Times opinion piece, and now in this podcast, Brett Finlay is holding up his hands and saying, "Hold on a second here." The pandemic's war on germs was never all that effective, is his argument. And those antibacterial wipes and hand sanitizers that everyone's using again? It could be setting us up for an onslaught of other health problems. So what to do?

[00:02:12.13]

Christopher Shulgan: The guest host today is Dr. Peter Nord, Medcan's chief medical officer, who explores Professor Finlay’s arguments and solicits his guidance on how to manage our complicated relationship with germs from here on out. Here's Dr. Peter Nord in conversation with Professor Brett Finlay.

[00:02:31.28]

Peter Nord: Hi, I'm Dr. Peter Nord, and I'm here with Professor Brett Finlay, one of the world's authorities on the microbiome and its relationship to human wellness. I'm really looking forward to this conversation, Professor Finlay, because it'll help a lot of people come to a surprising and ideally more nuanced understanding of the role of germs in our overall wellness. Let's start with a quick primer on the microbiome. What really is the microbiome?

[00:02:56.05]

Brett Finlay: Yeah, it's a term that everyone uses and has different meanings. Basically, it means all the microbes living in and on you. So you have all these microscopic creatures like bacteria and viruses and protozoa and single-celled animals, and there's this whole community of these things living on us, and we collectively call that the microbiome.

[00:03:15.04]

Peter Nord: Okay, so now that we've established that, let's talk about the hygiene hypothesis. Can you tell me the story of how it started, and how has that affected our understanding of germs and their role in human wellness?

[00:03:27.02]

Brett Finlay: Yeah, let's take a dive even further back into history when two very famous microbiologists, Louis Pasteur and Robert Koch, right around the late 1800s, they made the seminal discovery that microbes actually caused disease. And this was a major advancement in our knowledge of how diseases work, because up until then, they had no idea what caused things like cholera and plague. They thought it was swamp gas and these other things. So they showed microbes cause disease. And then Louis Pasteur showed that if you killed the microbes, you didn't get disease anymore. That's where the word "pasteurization" comes from: killing these microbes. So you put the two together, if microbes cause disease and then killing them prevents it, what do you do? Well, you want to kill microbes, right? And this is what society started to do. So we brought in sanitation, we brought in hygiene, we brought in antibiotics, we brought in vaccines.

[00:04:13.26]

Brett Finlay: And collectively, when you look at what infectious disease has done in the last 125 years or so, it's gone down very significantly. And you don't see the disease that we saw 125 years ago in developed societies. Yay! And we wish the story stopped there. This is a big success story. But what happens is, when we did all these things to the microbes, what we didn't realize is that we were killing all microbes, not just the bad ones, the germs and such. And by doing that, we decimated all the other microbes that live in and on us as part of a natural process. So what we started to wonder is that maybe we're starting to live too clean. And this is where the hygiene hypothesis comes from, that a fellow named David Strachan showed really that older kids brought home things for younger kids, and then they didn't develop things like allergies and stuff because they got more exposure to microbes. So the hygiene hypothesis really means that we've just started to live too cleanly, and we're depriving ourselves of sort of beneficial microbes. And as a result, yes, we get rid of infectious diseases, but we also have these other effects on all these many diseases that I'm sure we'll talk about in a moment, that are profoundly influenced by the microbes.

[00:05:21.26]

Brett Finlay: So once we figured that out, we thought well, heck, let's make sure we get exposed to all these good microbes. And I even wrote a book called Let Them Eat Dirt. It's how to raise your kids with their microbes. And we made all these profound discoveries of how microbes influence the early life, the effect on how the immune system develops, the brain develops, the gut develops. And so we've been on a campaign, well, you need to expose yourself to microbes. And then, bam! COVID hit. And this is back to 125 years, we didn't have antibiotics, we didn't have vaccines that worked, and we basically just jettisoned back to the late 1800s in terms of how we handle infectious diseases. And this is raising some very interesting questions now. Because, you know, okay, we've now been living in a bubble for 16, 17 months, and we haven't touched anyone other than who we're living with. And what's that doing to our microbes? We don't know all the answers yet, but we know in the past, whenever we've depleted our bodies of microbes, it doesn't end well for us. So that's where we are today. So there's 125 of the years in a nutshell.

[00:06:20.05]

Peter Nord: So Dr. Finlay, your February paper in the Proceedings of the National Academy of Sciences was really fascinating. I was just thinking about what triggered the need or the thought to write that article?

[00:06:34.02]

Brett Finlay: Yeah, so I co-direct a group, it's called CIFAR, Canadian Institute for Advanced Research. It's really a think tank of people working on many aspects of humans and microbes. So of course, you think microbiologists, but I'm talking anthropologists, evolutionary biologists, philosophers. And we were at one of our, of course Zoom by then, meetings and we started talking about, well, what's the pandemic doing to our microbiome? What is this affecting? And then we started to realize, holy smokes, this is going to be big, this is going to really impact on our microbes, because everyone's locked up, and we realized it was having different effects in different places around the world.

[00:07:11.11]

Brett Finlay: And so we suddenly realized, wow, this really needs writing. And then when you look at it from a philosopher's point of view, an anthropologist's point of view, versus a microbiologist's point of view, it's different. But it's the same kind of concept. But really, it was two purposes. One is to point this out. And second is to urge investigators to use this one-time amazing experiment to really follow what happens, because we're not going to—hopefully, never get a chance to do this in my lifetime again. Hopefully, it's another century before we have another pandemic. And to really look at what's going on. And, you know, what we've learned in the past is when we screw up our microbes, we screw us up. And we really believe we are screwing ourselves and our microbes during COVID for a whole bunch of reasons, and we better get our act together and learn about it and then do something about it.

[00:07:59.29]

Peter Nord: We can dive into a little bit more of the science that you've been leading. You know, your paper refers to the continued loss of gut microbial diversity, and ancestral—so that goes back a long way—microbes among a large swath of the world's population. This loss of diversity has accelerated over the past several decades, promoting the development of non-communicable diseases, including obesity, asthma, cardiovascular diseases and brain diseases. Can you elaborate a little bit more on that?

[00:08:28.15]

Brett Finlay: So if I told you that those diseases you just mentioned had any connection to microbes, you'd probably say I'm from Mars, because what does cardiovascular disease or obesity have to do with microbes? Well again, what we've learned in the last decade, it has a lot to do with it. And there's microbes that are influencing these diseases. One example is asthma and early-life microbes. So we know they influence how the immune system develops, which actually affects asthma. So if you're born by a C-section versus a vaginal delivery, you actually have a 25 percent higher chance of getting asthma, just by how you stick your head out in this world, because you don't get the vaginal fecal microbes from your mother. And obesity, you actually have a 30 percent higher chance of being obese if you're born by C-section, because you're not getting these microbes. And that's just one example.

[00:09:12.04]

Brett Finlay: And obesity, you can take, say, for example, feces from a fat mouse and put it in a thin mouse, it gains weight. You can do the experiment the other way around: thin mouse feces into fat mice, they lose weight. Heavyset people feces going into thin mice, they gain weight. So we now know there's actually quite a tight link between the microbes and obesity. And even cardiovascular disease, which is, you know, as you know, atherosclerosis and heart attacks and strokes, up until recently everyone thought oh, it's just cholesterol and things like that. Well, we now know that when you eat red meat, the microbes break down components of red meat that basically potentiate these diseases and, for example, you can even inhibit the microbial enzymes that do this in mice, and you actually prevent cardiovascular disease in a high red meat diet. So all these things are now linked to microbes.

[00:09:57.13]

Brett Finlay: And there's even a bizarre concept that you can transmit your microbes from one person to another. So maybe obesity is actually kind of transmissible through the microbes. For example, if you have an obese friend, you have a 40 percent higher chance becoming obese yourself. We don't know that's through microbes yet, but I mean, there's a lot of smoking guns there. So it's a fascinating think experiment, shall we say, about what we're doing to our microbes these days, and what's going to happen.

[00:10:20.11]

Peter Nord: So be careful who you're kissing.

[00:10:22.28]

Brett Finlay: Well, yes. Because when you kiss a person, you transmit 80 million microbes. And this is a normal process. And maybe choose your friends wisely, you know? I don't know if these dating apps have microbial compositions associated with them but, you know, inflammatory bowel disease, for example, the spousal rates of inflammatory bowel disease are way higher than they should be because you're not genetically related to your spouse, yet they have these crazy rates. And for example, when people from India, which has very low IBD rates, they move to Canada, the US, Europe, they have the highest rates of anyone in terms of inflammatory bowel disease, and they haven't changed genetically. So again, we think there's microbes associated with this. And spouses of IBD people have very, very high rates of this disease. So yeah, maybe think about who you're kissing these days.

[00:11:08.22]

Peter Nord: Yeah. And I know this is also something that generally hasn't really been taught in med school. So a lot of physicians that are out in practice really aren't up on all the details that are around this. I think back to the whole H. pylori, and it was crazy talk that a bacteria could cause gastritis or ulcers in the stomach. And now we take it as fact. The community kind of recognizes now, the physicians, that H. pylori as a bacteria causes stomach troubles.

[00:11:38.14]

Brett Finlay: Yeah. And they won a Nobel Prize for it, too. And I think the same applies to the microbiome. I mean, it's really coming fast. And, for example, at our university and many others, people don't bother teaching microbiology anymore, because there's more important things to be taught. You know, that's not a big problem, and they've actually canned it from the curriculum. Yet when I take the top 10 reasons why every Canadian or American dies, they're all the diseases that we see, you know, cancer, Alzheimer's, cardiovascular disease, et cetera, nine of those 10 now in the last decade have had strong microbial links. Even brain diseases like Parkinson's, for example, we now know that starts in the gut 30 years before because of your microbes, so what we thought was a brain disease now is microbes. So it's a whole new way of thinking of medicine.

[00:12:22.27]

Brett Finlay: You're right, it hasn't hit the medical curriculum yet, but it's coming. And I think that the most obvious way is through fecal transfers, you know, putting poo from one person into another. It sounds horribly gross, but this has been shown to really work with a disease caused by something called Clostridium difficile or C. diff. And this is a wonderful sort of proof of principle that basically microbial transfers alone can cure a disease that would otherwise kill you. So these things are now starting to go into clinical trials, and taking mixtures of certain microbes and put them in people so you don't have to fecal transfer and cure diseases such as IBD and C. diff, for example. So it's coming. But I mean, most patients have to wait until they have the actual clinical trials and proof and they have a little drug they can use, kind of thing. And so it's not really there yet. And ironically, I think the public is more ahead of physicians in this area because they're reading Google, and it's not too hard a concept to explain about all these microbes happily living in us and doing good things.

[00:13:17.14]

Peter Nord: Yeah, conceptually rather simple. And back in my hospital career, I remember not a number of years ago, I had a patient who had chronic C. diff, and we did a fecal transplant, and within a week—they'd been struggling for months with trying to eradicate this C. difficile, with higher doses of antibiotics and broader spectrum antibiotics. And it was the fecal transplant that actually cured them in the end. So I even have a personal N of one trial that was 100 percent successful. So that was great. You know, again, once you get over the gross factor, they really appreciated it.

[00:13:50.07]

Brett Finlay: Yeah. No, it's now a clinically-approved treatment, you know, if you don't respond to normal treatments. I mean, ironically, C. diff infections are caused by taking antibiotics. So it's hard to think that antibiotics are going to cure them, kind of thing. Because what happens is that you fill people up with antibiotics, say before hip surgery or something, and that kills off all these microbes that are normally in there. And then C. difficile, which is a pathogen, comes in and the competition is removed. So I tell my students it's like walking into a full classroom versus an empty classroom and trying to get a seat. So C. difficile walked into this empty gut, and it's easy to take hold and cause this disease.

[00:14:25.17]

Brett Finlay: Now fortunately, when you put in a whole bunch of other microbes, they displace C. diff, and then that's why it actually seems to work. And it's a great example. It's also being used fairly well now for also colitis, one of the IBD diseases. And there's even some really promising trials coming out in autism, for example, of improving the kids' mental capacities due to these fecal transfers.

[00:14:46.05]

Peter Nord: Yeah. And IBD is inflammatory bowel disease for our listeners. And you mentioned dating apps, and one of the things that we've been seeing recently during the pandemic is one of those criteria on the dating app is vaccination status. So we find ourselves in the pandemic, and you hinted at it before, so how has that changed things over the last 16 months?

[00:15:07.14]

Brett Finlay: Well, first of all, as a scientist—and I hate to say it, but this pandemic is probably one of the greatest experiments we've been able to do. When else do you get to shut down the entire world and follow the experiment? So microbiologists, of course, are following all these things. But I also think that we're changed. I mean, I know even I find myself when I look at someone, or you're close to someone, you kind of back away from them. And socially, we've changed. And we are social creatures. And so the concern is that we will change our habits, we will all continue to wear masks longer. And where I think we'll see the biggest effect is the, I call them the bookends of life: the really young and the really old, because that is when these microbes have the largest effects.

[00:15:44.29]

Brett Finlay: And, you know, we talked a bit about kids being born, and how their immune system develops and stuff. And imagine a kid born during COVID versus pre-COVID. It's a very different world. They're not off to daycare, they're not seeing extended family and things, and they're contained in their household. And so there's worry there. And the other worry is the elder people. So, you know, people that have been locked in old folks' home, they've only seen their care workers in full PPE for a year. They're not seeing the microbes they saw previously, and all studies show that really influences healthy aging. And there's concern that that will have a drastic effect on their health as we go down the lines.

[00:16:23.00]

Peter Nord: And that's short-term and long-term, I would imagine.

[00:16:26.21]

Brett Finlay: Yes, very much so. I mean, everyone says, "Well, can you prove it?" And all I can say is not yet, but like I say, whenever we know that we disrupt our microbes due to sanitation or antibiotics or any other measure, these do have consequences. And my guess is we're going to see, for example, rates of asthma and obesity increasing about five years from now when they happen to the kids who were born during COVID, because they don't have the beneficial microbes that they should normally get just by a healthy life.

[00:16:55.13]

Peter Nord: And there is even some evidence that the status of a person's microbiome may actually influence their susceptibility to getting COVID. Can you tell us more about that?

[00:17:05.09]

Brett Finlay: Yeah, there's some papers looking at, you know, people that get COVID versus don't, and what are their microbiomes. The problem with the microbiome is it's incredibly complex. When sequencing came along, we can now sequence all these microbes that we couldn't previously grow. So that's how we knew they were there. But these are massive. Millions and millions of sequence reads, and you get this very complex readout. And so it's hard teasing out these things. Because the other thing you need to know is that every person's microbiome is different from everyone else's. You and I have completely unique ones. Now your microbiome is more close to someone you're living with than, for example, your identical twin brother that lives on the other side of the world, because you share similar environments. But each person is unique. So if everyone's unique, how do you say what's a conserved microbiome? And that's where the difficulty comes in. As you said, it's an easy concept at a high level, but once you get into the details, it's incredibly complex. And are these two bacteria that are different between two people, does that mean anything or not? Are they really the same or not?

[00:18:04.25]

Brett Finlay: And so we struggle with defining that. We're getting pretty good at figuring out what's a diseased microbiome, say, for example, obesity, or Parkinson's, though we call it dysbiotic. It's a term that means it's different than normal. But if you say, "What is a normal microbiome?" That's a hard one to actually define. Now you can get your microbiome tested. You can send it away to these various test places. And people ask me, "Well, should I do this?" And I say, "Well, you'll get a long list of microbial names, and if you're a real geek and you like wallpaper of microbial names, then it's useful." But to the average person, it doesn't mean anything. And the problem is, we don't know what to do with that yet. You can't walk into your doctor's office with your list of microbes you have and say, "Can you fix me now?" Because we just are not there yet.

[00:18:48.13]

Peter Nord: Yeah. And, you know, keeping with the theme of COVID and the pandemic, it's easy to imagine how some risk-averse people who are now a bit gun shy due to the pandemic, are staying fully masked and avoiding things like handshakes and crowded areas, like what you might see at sporting events or concerts. Could that have a harmful effect on the microbiome, because we're not exposing it to as many germs?

[00:19:10.19]

Brett Finlay: Yeah, I personally think so. I think that humans have evolved as social creatures. We've always shared microbiomes from birth on. And getting back to the hygiene hypothesis we talked about earlier, we're living too clean. It gets rid of infectious diseases nicely, but what it doesn't do, it actually harms you with all those other non-communicable diseases we talked about. For example, in the States and Canada we're much more hygienic than other places, just because of the way our societies are built, and that's why we have higher levels of all these non-communicable diseases. And when you look around at what's killing people in, say, the United States, it's very different than, say, in Africa, where infectious diseases are still a major problem. So they got to still deal with the hygiene. But, you know, the chance of you going out to the playground or the park and getting polio are basically non-existent now in our society.

[00:19:58.27]

Brett Finlay: And so, up until COVID, I was consoling people. Well, you're not going to die of rheumatic fever or cholera. You know, that's not what kills people these days. You're fine, you can go outside. You don't have to use hand sanitizer on your child every time it goes between the slide and the swings and back again. You know, chill. This is good for you, you know? God gave you an immune system, use it, kind of thing. But then COVID has really thrown a wrench in it, and I think that we're going to have to pay attention as we come out of COVID, what do we do for us and our microbes? Because we know that's going to affect us down the line.

[00:20:32.01]

Peter Nord: Yeah, so what do you then recommend? We're going to have listeners that are going to be thinking, like, do we stop it with the hand sanitizer? Do we stop wiping down our surfaces? You know, initially, we were wiping down groceries and wiping everything. And we've started backing off on that, and the studies have shown that COVID really isn't—the fomites and the surfaces really aren't a source of transmission of the virus. And so do we stop the antimicrobial wipes, the sprays that are being marketed pretty aggressively right now? Or even, like, hand washing with soap?

[00:21:06.09]

Brett Finlay: Well first of all, those things really don't do anything for COVID as you point out anyways, so why are you doing them in the first place? You're not exposed to things. But assuming you still like to spray things down, I would argue, stop it. Go get your vaccination for COVID, because this is so important to drive COVID numbers down. And assuming most people get vaccinated, COVID will, I think, be a residual disease for those that aren't vaccinated, and some people very rarely, but it will probably be much less than the flu, for example, and normal things we see in society. And, you know, during flu season people do tend to be a bit more careful, because, you know, they cough into their sleeves, for example, and they are a little more hygienic in that sense. So really, it's a balance. What is my chance of getting infection, so I use hygiene, or my chance of living a normal, developed microbiome kind of exposure.

[00:21:52.19]

Brett Finlay: And if the infectious diseases threat is not very high, we argue it's really good for you to get exposed to these microbes. If the infectious disease is very high like during COVID at its prime or 125 years ago, that's when hygiene rules. And we've got to take these hygienic measures. But all those things you alluded to, they don't have any effect on COVID. So there's no antibiotic that works on COVID. It's not surface transmitted, as you say. So don't worry about it. It's not on your groceries, it's not on your counter. And so unless you're putting raw chicken on your counter with salmonella on the outside, then you really should wipe it down. But I generally say soap and water before dinner, make you feel clean, but lay off the hand sanitizer. All it does is kill the good microbes on your skin, and you're more susceptible to skin infections anyways.

[00:22:38.17]

Peter Nord: Well, we've been focusing on sort of the negative side, so let's move more to the positive side. So what can we do to bolster our micro microbiome?

[00:22:47.09]

Brett Finlay: I think the first thing is to realize we have probably damaged our microbiome. And once you realize that, you think, "Well, how can I fix it?" And probably the easiest way is diet. There's no better way to get a healthy microbiome than improve your diet. So think Mediterranean diet-type things, you know, lots of fruits and vegetables and nuts and legumes and fish, and less red meat, less high dairy fat, less white sugar type things. Study after study shows that this is immensely beneficial for your health, no matter what stage of life you are. And we just published a really interesting study where there's a version of the Mediterranean diet, it's called the MIND diet, which is a mix of the Mediterranean diet and something called a DASH diet, which is cardiovascular disease. It's the same thing. You know, fruits, nuts, legumes kind of thing. If you follow that, we showed that your chances in women of getting Parkinson's, its onset is delayed by over 17 years, and men by over a decade, by just following what you eat. Now given that Parkinson's usually onsets later in life, 60-plus, the chances are you just won't get Parkinson's. You'll die of something else first because of this. So diet is your first friend.

[00:23:54.09]

Brett Finlay: People often ask about probiotics, but probiotics we can talk about later if you want are not really there yet. We don't have good probiotics that are really going to fix you because current probiotics really, for example, lactobacillus, and bifidobacterium, which are common ones, these are actually from the woman's vagina, and they have nothing to do with the gut world, it's a completely different world. It's like taking a penguin and putting it in a desert and asking it to survive. They just don't. And that's why you have to take these billions and billions of probiotics every day, because they flush through you. So we don't have good probiotics that colonize the gut and then fix it.

[00:24:27.05]

Brett Finlay: Fermented foods is a good way of doing it. You expose normal microbes that are used to living without oxygen, and they often help you in that sense. And then I think getting outside is really important, even in COVID. I mean, you can't go to a rock concert, but you can certainly go in your backyard and you can go play around in the dirt, you know, or go to a petting zoo or something. You know, expose your kids to microbes. So yes, there's natural exposure. I mean, think of how our ancestors lived. Go back, you know, 1,000, 2,000, 10,000 years. And now think about how we live, parked in front of the computer. When's the last time you got dirt under your fingernails? You know, unless you're a gardener, this never happens, right? Yet that's how we evolved. And we are behaving so badly from our evolutionary point of view. And, you know, that's why we're losing a lot of our microbes.

[00:25:12.01]

Brett Finlay: And then exposures to each other, too. I really do think that if there is no raging, infectious diseases, definitely hug your neighbour, you know? The French have it right: kiss each other on two cheeks kind of thing. Expose yourself to microbes. And eldercare places, I personally think that dogs and grandkids and everyone should be allowed to roar through these places to allow these elder people to gain these nice young microbes that actually influence their healthy aging. And we know that actually has a big beneficial effect.

[00:25:41.23]

Brett Finlay: There's exercise. Exercise is a terrific way of improving your microbes, which then improves you. You increase the anti-inflammatory microbes—this actually has a beneficial effect. And so you don't have to be a marathon runner, but you should be out just being active. And I mean, this is not news to anyone, but we now know it's news because it works for the microbes that actually benefit you, as well as your heart and things like this. And we all live stressful lives, and stress is not good for your microbes. It drives them into a really inflammatory-type state that really seems to potentiate many other diseases. So maybe post-COVID is chill out a bit. Maybe it's taught us that we don't have to go 5,000 miles an hour all the time. Maybe just sit back, enjoy the life and play with the kids, and go outside and eat well, and you'll add a decade to your life.

[00:26:27.10]

Peter Nord: Great advice. And especially at a time when public health agencies around the world have been telling us the opposite. You know, stay at home, don't touch anything, don't go outside. If you do, wear a mask, so you're not actually interacting with the environment. So as you said, what a challenging time for our microbiome when we're being told exactly basically the wrong things to do because of the extreme situation that we're in from a pandemic perspective.

[00:26:55.10]

Brett Finlay: Yes, this gets back to our hygiene talk again. It's a balance. Am I going to get infected, or am I going to live healthier? And I think especially in Canada, US, and Europe kind of thing, as the vaccine drives that down, I think we have to rethink things. And there's going to be carryover. I mean, it's going to feel weird walking out into public without a mask. It's going to feel really weird shaking your neighbor's hand or embracing someone, but I think that's naturally how we've always done it. And I think we should revert to that behaviour if we at all can.

[00:27:22.28]

Peter Nord: There's been a lot of transition fads almost that have been surrounding this, that have, I think, almost undermined the science that that you and others are putting forward. I guess that would be a bit of a challenge as well.

[00:27:36.23]

Brett Finlay: It is. It's a very trendy area. And if you're into probiotics, I would say go Google the words "probiotic chart." And there's a site for both the US and Canada that gives a list of all the probiotics, and it tells which probiotics have been proven in clinical trials for which things. And you'll see there are a couple of probiotics that work for a couple of things—sometimes. But, you know, most of them are not. And the analogy I use is like, you want a new pair of running shoes, you walk into a sports store, and there's an entire wall full. There's joggers, basketball shoes, tennis shoes and hiking shoes. And you don't just grab the cheapest pair and walk out. And that's kind of when you walk into a health food store. And because probiotics are not regulated by the FDA, they tend to be quite a bit looser in terms of their health claims and things. So that's one way. But I think, just think how we live, and put it in perspective. We tend to get, "Oh my God, I'm gonna die tomorrow if I go outside!" Well, maybe you won't if there's no COVID out there. We lived pre-COVID, we will live post-COVID, especially if you have a vaccine. So I think, yeah, just realize we've impacted our microbes and realize there are things you can do to help them because they're your friends, and they are going to help you down the line.

[00:28:48.01]

Peter Nord: Well, that's a great place to wrap up. That's a great positive message, for sure. Dr. Finlay, I learned a lot today. I hope our listeners did, too. Thanks so much for your time today.

[00:28:57.09]

Brett Finlay: Yeah, absolute pleasure. Thank you very much.

[00:29:08.04]

Christopher Shulgan: That's it for this episode. Find Professor Brett Finlay on Twitter @finlaylab. That's F-I-N-L-A-Y-L-A-B.

Christopher Shulgan: I'm executive producer Christopher Shulgan. Find show notes, links and full episode transcripts at EatMoveThinkpodcast.com.

Christopher Shulgan: Eat Move Think is produced by Ghost Bureau. Senior producer is Russell Gragg. Patricia Karounos is associate producer. Social media support from Emily Mannella.

Christopher Shulgan: Remember to rate and subscribe to Eat Move Think on your favourite podcast platform, and follow our host Shaun Francis on Twitter and Instagram @shauncfrancis—that's Shaun with a U—and Medcan @medcanlivewell. We'll be back soon with a new episode examining the latest in health and wellness.

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