When you think of the microbiome, you probably think of your gut. But bacteria live all over your body. And they’re incredibly numerous; you play host to about as many microbes — a hundred trillion of them — as you do human cells.
As my guest will explain, these microbial ecosystems are not only ubiquitous but hugely influential for your health — impacting everything from your weight and mood to your risk of developing many diseases.
Dr. Brett Finlay is a microbiologist and the co-author of The Microbiome Master Key. Today on the show, Brett explains what the microbiome is, how modern life — including our overemphasis on hygiene — has damaged it, and how the quality of your microbiome is connected to nine of the top ten leading causes of death, as well as everything from depression to Parkinson’s. Brett also shares how we can boost the health of our microbiome, including whether probiotic supplements are effective, how something as simple as flossing your teeth can cut your risk of Alzheimer’s by 50%, and why you might want to let your dog lick you in the face.
Resources Related to the Podcast
- Let Them Eat Dirt documentary
- AoM Article: How and Why to Eat More Fiber
- AoM Article: Don’t Be a Stick in the Mud — Why You Should Let Your Kids Get Dirty
- Probiotic gum
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Read the Transcript
Brett McKay : Brett McKay here and welcome to another edition of the Art of Manliness podcast. When you think of the microbiome, you probably think of your gut, but bacteria live all over your body, and they’re incredibly numerous. You play host to about as many microbes, 100 trillion of them, as you do human cells. As my guests will explain, these microbial ecosystems are not only ubiquitous, but hugely influential for your health, impacting everything from your weight and mood to your risk of developing many diseases. Dr. Brett Finlay is a microbiologist and the co-author of ‘The Microbiome Master Key.’ Today on the show, Brett explains what the microbiome is, how modern life, including our overemphasis on hygiene, has damaged it, and how the quality of your microbiome is connected to nine of the top 10 leading causes of death, as well as everything from depression to Parkinson’s. Brett also shares how we can boost the health of our microbiome, including whether probiotic supplements are effective, how something as simple as flossing your teeth can cut your risk of Alzheimer’s by 50%, and why you might want to let your dog lick you in the face. After the show’s over, check out our show notes at aom.is/microbiome.
All right, Brett Finlay, welcome to the show.
Dr. Brett Finlay: Hey, thanks for having me.
Brett McKay : So you are a microbiologist and you study how microbes can cause disease in us, but also you’ve done a lot of writing and research and education on our microbiome that we all have inside of us, on us. We’ll talk about that as well. I’m sure a lot of people have heard of the microbiome. They may have seen advertisements for supplements or even food that’s supposed to help your microbiome. But I imagine if you asked a lot of people, like, “What is the microbiome?” And they’d be like, “Oh, kind of hum and ha.” So let’s start with this question. What is the microbiome?
Dr. Brett Finlay: That’s a good question. Basically, it’s a collection of all the microbes living in and on you. So most of the time we think about bacteria just because they’ve been easy to study, but it also includes viruses, includes eukaryotic protists, single cell, things like yeast, for example. So really it’s the collection of all the microbes that are living in and on us, and they’re all invisible to the eye, but there’s lots of them there.
Brett McKay : Okay, and you said in the book that we are more microbial than human. What do you mean by that?
Dr. Brett Finlay: I don’t mean to insult anyone, but so basically there’s a similar number of human cells in us as there are bacteria. So they’re about one to one. So there’s many bacteria living in and on you as there are human cells, and these bacteria encode about 100 times more genes than the homo sapien genome. So you put those things together. I love to tell my students they’re more microbial than human just because there’s so many of these microbes in and on us.
Brett McKay : So give us like a number, like a rough estimate. What would that look like?
Dr. Brett Finlay: Yes, about 100 trillion. What does that mean? Well, let’s talk graphics here. If you take a piece of feces the size of your fingertip, I know it’s a gross analogy, but hang in there. There are more microbes in that piece of feces than there are humans living on this higher planet. So I jokingly say think of the genocide every time you flush the toilet kind of thing. There’s a lot of them on.
Brett McKay : I mean, if you were able to clump all this into one mass, like how much would that weigh? Like how much of our body weight would be microbes?
Dr. Brett Finlay: Yeah, it’s about three or four pounds. So we kind of think the microbiome is sort of another organ. It’s about the size of your heart, for example, collectively, but they’re dispersed. Most of them are in the gut, the lower gut, but they’re also all over many other parts of our body as well.
Brett McKay : Yeah, because I think most people, when we think of the microbiome, we’re thinking of, we’ll talk about this idea of gut health, but as you said, it’s other places besides our gut. So where else do we have a microbiome?
Dr. Brett Finlay: Right. I mean, the gut’s the most obvious, and basically the bacteria get more and more numerous as you go down the gastrointestinal tract, and they’re the most right near the very bottom in what’s called the large colon, the large intestine, and that’s kind of really a paste of bacteria. And there’s 10th to the eighth, 10th to the ninth bacteria per gram of feces there, phenomenal numbers. Now, bacteria aren’t in us, so generally the blood and inside our body is generally considered sterile unless it’s infected, but they’re basically on us. So wherever our body is exposed to the outside, so on your skin, for example, and like all living organisms, they like moisture, so there’s more microbes in your armpits and groin than there is, say, on your forearms. They’re in your mouth and the upper nasal tract. They’re in the urinary tract, especially in women. And so basically wherever your body is exposed to the outside, there’s microbes that are there, kind of serving as this filter between us and the outside world.
Brett McKay : An interesting point you made in the book, and I had to think about this, and I was like, “Yeah, that makes sense.” We typically think of our gut as the inside of us, but technically it’s the outside.
Dr. Brett Finlay: It’s a tube running through us, that’s right. It’s really outside, it’s just this one open tube that goes from the mouth to the anus, and there’s lots of microbes in there.
Brett McKay : Yeah, I had to think about that for a little bit. I was like, “Oh yeah, it is, it is on the outside.” It’s the outside going sort of like a hole through us.
Dr. Brett Finlay: It’s a tube, that’s right.
Brett McKay : It’s a tube So, okay, the microbiome, it’s bacteria, it’s fungus, it’s yeast, it can be viruses, but not all of these microbes cause sickness or illness. So like, what’s the difference between, let’s say, the bacteria that causes us to get the stomach flu compared to the bacteria that’s just always there and not doing anything to us, or maybe actually doing good stuff to us?
Dr. Brett Finlay: Yeah, I mean, the history of microbiology has focused on bacteria that cause disease called these infectious diseases. So that’s salmonella causing typhoid fever, that’s listeria causing meningitis. But there’s only about 100 types of bacteria that can actually cause disease in humans. Yet we have thousands and thousands of microbial species living in and on us, and these are just basically normal residents. Under normal situations, they don’t cause any problems, and we now realize they’re actually beneficial there. And so there’s kind of these two camps, those that cause disease and those that just sort of live on us and really symbiotically and are actually beneficial for us. And so, yeah, we’ve historically focused on the bad guys, but ironically, we now start to focus on the good guys and realize they actually have a large role to play in our general health and well-being.
Brett McKay : Okay, so how does this bacteria get on us? Like, where does it come from?
Dr. Brett Finlay: Well, there’s bacteria everywhere. You can’t see them, but they’re everywhere. I mean, I jokingly say the world is coated in a veneer of feces and microbes. The soil is full of microbes, for example. I mean, every food you eat, there’s microbes in there until you cook them, but they’re alive until you cook them. And every time you put your hand in your mouth, for example, you’re introducing microbes. Like, there’s microbes all over your cell phones, all over the toilet seat. They’re all over the world. It’s a gross concept when you think about it, but they’re just there, and this is normal, and they’re everywhere.
Brett McKay : Then you also talk about, throughout our lifespan, we get kind of hit with these microbes in a healthy way. And it happens at the very beginning of life. Once you’re born, that’s when you get hit with a lot of these microbes that are potentially good for you.
Dr. Brett Finlay: Yes, that’s right. I mean, I did write another book called Let Them Eat Dirt, and we talk all about how important this early life microbes is. And they really are important for our development. Generally, a fetus, so it’s not born yet, is sterile, as far as we know. There are some microbial signatures, but we haven’t shown there’s live microbes in there. But the second you’re born, I mean, think about birth. It’s a very messy business. But ironically, that first big gulp you take, it’s full of vaginal fluids, feces, and all these other horrible things. But these are full of microbes. And ironically, that’s really good for the baby and really important. So as soon as you’re born, you get microbes. And anyone that has a breastfed kid, the feces is quite sweet-smelling and stuff. But the second you introduce solid foods, it becomes a very different story because the microbes have now changed. And generally, once you’re through adolescence, pretty much entire adult life, your microbiome is pretty constant. It doesn’t really change unless you do something drastic like move or go into antibiotics or change diets. And then as you age, post-65, the microbes do shift. And that seems to create some of the problems associated with aging.
Brett McKay : Let’s talk about that one book you wrote, Let Them Eat Dirt. Because I remember when that came out, I think someone wrote an article for our website, and they cited that book. But the importance of your kids playing in the dirt, getting out in nature, playing in mud, et cetera. Why is that so important in childhood development?
Dr. Brett Finlay: It’s really important. It’s become more important. And I urge your listeners to go to YouTube and look up Let Them Eat Dirt. We have a nice one-hour documentary. And so you don’t have to read the whole book. But what happens is these early-life microbes, they basically help program our body. We know that we’re getting born to microbial worlds. They play a major role in developing our immune system. And this can determine whether you get asthma or not, for example. They play a big role in obesity. They help our gut develop. They help our brain develop. We know that animals don’t have microbes. They don’t develop normally. You need these microbes as a part of us. So when you think of how we lived as a species for millions of years, we were just outside in lots of microbes everywhere. This is actually an important part of us. So in these days, when a kid is born by a sterile cesarean section and then stays in a sterile apartment, doesn’t get outside and stuff, you’re actually depriving the kid of the normal microbes that they need for the normal development. And then we see the appearance of these diseases, such as asthma and obesity and things that are associated with an imbalanced microbiome early in life.
Brett McKay : Okay, so hopefully we can talk about the role the microbiome plays in things like obesity here in the rest of our conversation. Because you dig into that, particularly how it can influence obesity as we get older. This is what this book’s about. The Microbiome Master Key is about the microbiome past childhood, like when you’re in your 30s, 40s, and then beyond. So what does a healthy microbiome look like? And I imagine it’s going to look different in different parts of the body.
Dr. Brett Finlay: Yeah, that’s actually a really hard question to answer. For years, we’ve struggled. We’re really good at saying what a non-healthy microbiome looks like. We could tell you pretty quickly, “Oh, you’re going to head towards inflammatory bowel disease or Parkinson’s or whatever.” We actually really struggle. What is a good microbiome? Basically, it’s a very diverse ecosystem. We all know that diversity in ecosystems is really important. You want lots of microbial species there. Generally speaking, from the gut point of view, you want microbes that are good at digesting fiber because that is a very beneficial effect for us and as for the microbiome. You don’t want microbes that are generally associated with inflammation. These are microbes that have something called lipopolysaccharide, which is a highly inflammatory molecule. It basically excites the host immune system and causes unwanted inflammation. That’s a cornerstone to unbalanced microbiome. But there is no one perfect microbiome. You’re right. Not only each person has a unique set of microbes, so there’s no one conserved microbe in all people across the world. Different areas of the world have different microbiomes.
Different parts of the body have different microbiomes. We struggle with saying, “Okay, this is the perfect, this is what you should head for,” kind of thing. We know what’s bad, but we have trouble saying what’s good.
Brett McKay : What’s bad? What does a bad one look like?
Dr. Brett Finlay: The bad ones are basically the increase in these inflammatory microbes and decrease in the short-chain fatty acid. The fiber fermenters, for example, that is generally bad. That actually generally also kicks in later in life when you shift towards a more detrimental type microbiome. If you’re eating a highly processed food diet, lots of white sugar, white flour, all the stuff that we love to eat, that ironically is actually bad for your microbiome because it’s already broken down, so you’re really starving the fiber-digesting microbes down in your body. That actually contributes to problems like obesity and other type 2 diabetes and other issues.
Brett McKay : Something I’ve seen, I’m sure people have seen this as well, they’re like, “Well, I want to figure out what my microbiome is like because I want to optimize.” Everyone’s about optimizing their health. There’s tests you can take where you actually poop and then you swab your poop and then you mail it. These companies can tell you, “Oh, well, you have a healthy microbiome, you have an unhealthy.” Is there anything to that? Do these tests actually tell you anything useful?
Dr. Brett Finlay: Really clinically, no. There’s nothing clinical done yet. These companies say you should do it every few weeks so we can tell you what you’re doing and stuff. It gives you a general idea. If you’re a real nerd and want to know what’s in you, it’s really cool. If you’re a microbiologist and number of species names, it’s really fun to put up in a poster on your wall. But really, there’s no clinical indications that you could say, “Okay, based on this, I should do that,” kind of thing. Right now, it’s a general interesting, but it’s really not a medically proven test, shall we say.
Brett McKay : Okay, so it might be a great dirty Santa person.
Dr. Brett Finlay: It’s fun.
Brett McKay : It’s something fun.
Dr. Brett Finlay: It’s really cool, yeah.
Brett McKay : Hey, Dad, you want to know what’s in your poop? Here we go.
Dr. Brett Finlay: Sure. You get your genome sequence and you’re 2% Neanderthal. You get your microbiome sequence and you’ve got some bacteroides and all the cool things in there. But what do you do with that? The problem is what do you do with that? And right now, we’re lacking the information to say, “Based on this composition, you should do this.” That’s where we stand.
Brett McKay : Are there moves to make these tests more useful? Is that something companies and researchers are trying to do?
Dr. Brett Finlay: They’re thinking about it. One thing we can say is that you can predict many diseases based on the microbiome composition. You can tell if a person is obese just by their microbiome. We have some work showing that we can predict whether someone has Parkinson’s or not based on the microbiome. But then knowing that, say, “Okay, well, what do I do to fix it?” That’s where the difficulty comes. The problem is standardizing it and making a universal test. It’s been difficult. Like I say right now, there’s no clinical test you can get done for the microbiome.
Brett McKay : Something people might have heard, and you talk about this in the book, and you mentioned this earlier too, how we’re raising kids these days where they’re not exposed to microbes because we keep everything very sterile and clean. That’s having effects. How has modern life disrupted our microbiomes?
Dr. Brett Finlay: Yeah, these are just thought experiments to think, how did we live, I don’t know, 10,000, 100,000 years ago versus how we live now? I mean, historically, we were heavily in contact with the environment at all times. It was a dirty environment, and we obviously got a lot of microbes. We also died of infectious diseases very early. But then when we started to realize that germs cause disease, society about 120 years ago went on a major hygiene campaign. So let’s clean the world up. Let’s bring in hygiene. Let’s bring in hand washing, hand sanitizer. Antibiotics were invented. So we really cleaned the world up, and that had a spectacular effect on decreasing infectious diseases. I mean, it used to be that, you know, most of your kids would die in childhood. Now, very few kids die in developed countries of these diseases. But what we now realize is that, oops, maybe we cleaned the world up too much, and the collateral damage of getting rid of all microbes, we now realize that some of these are beneficial. So antibiotic use is a major issue associated with microbiome disruption. Hygiene, as we’ve talked about already, is a big thing.
I mean, you think how kids are raised these days when the last time they got to roll in the dirt and get dirty and everything, “Oh, no, you’ll get dirty.” And COVID, of course, really set us back because we went back to more of a hygiene-type world. But we’ve been trying to push for the trend that we need a balance between if it’s potentially infectious, stay away. But if it’s potentially non-infectious, embrace the microbes. And that’s where the conflict lies. And pretty much all of modern life is around sanitation. You think how we design buildings. We, you know, get in an airplane seat and wipe it down with some ethanol swab. You know, we wear masks all the time now. The world has really changed to be hygienic. It’s good for infectious diseases. It’s terrible for your microbiome.
Brett McKay : And besides the hygiene aspect, as you mentioned earlier, diet. Our diet has become more standardized, highly processed, and that’s not good for the microbiome as well.
Dr. Brett Finlay: No, that is not good at all. I mean, you think how our ancestors ate. They were chewing on nuts and fiber and plant stuff and things. And we don’t do that anymore. We have the nice processed foods. And the problem is, like I said, they’re already broken down. So let’s say you ate a stick of celery, for example. It’s full of fiber. We don’t have the enzymes to break down fiber. Microbes do. So the body relies on it going to the large intestine where the microbes chew away on the fiber. And ironically, that’s beneficial because the products of this fiber are anti-inflammatory. They help the body grow and things. If you’re eating white sugar and white flour and traditional Western diet, it’s already broken down and really there’s nothing for the microbes to do. So ironically, most of it gets absorbed in the upper small intestine and doesn’t even make it down to the large intestine. So you’re kind of starving your microbes there.
Brett McKay : Yeah, I think the key is that our processed diets that we have, it’s making our microbiome in our gut particularly less diverse. And it’s not just an individual issue. It could potentially be a generational one. I think you said in the book that when people eat a low-fiber, highly processed diet, they lose certain gut bacteria and then they pass on a less diverse microbiome to their children. And you kind of make the argument that if we don’t change our diet, we could, for example, lose the bacteria that we need to digest fiber.
Dr. Brett Finlay: Yeah, the studies have shown that in my studies, if you deprive them of fiber for about four generations, you can’t go back. And many of us microbiologists are concerned that we’ve evolved with all these microbes over the millennia and suddenly we’re taking them out of our evolutionary equation. We’re worried that a generation or two from now, we’ll suddenly wake up and realize, “Oh no, we’re missing these key microbes that basically make us human and what do we do about it?” So there’s even biobanking going on now trying to preserve some of these in some of the uncontacted civilizations around the world and trying to preserve it. But yes, there’s a real concern that there’s these missing microbes that generation after generation, we’re basically getting less and less diverse and we’re losing all the microbes that we need. And the worry is that we’re going to put ourselves in a position where suddenly we can’t go back and that’s really scary.
Brett McKay : All right, so modern life has disrupted our microbiomes because we’re too hygienic. You’re not saying hygiene’s not good, but taking it to the extreme is not good. Antibiotics are a great thing. It saved a lot of lives, but if you just use it for anything, that’s not good because you kill the good bacteria and you even make the bad bacteria resistant to the antibiotics. They become less useful. And then also just our diet is messing that up. So let’s talk about some of the potential health consequences of not having a healthy microbiome, of having an unhealthy one. Let’s talk about the Mecca of microbes is what you call this area, the gut. What makes up our gut exactly?
Dr. Brett Finlay: Yeah, I mean, gut is obviously where you digest food. You chew it, it goes down to the stomach, then on to the small bowel and the large bowel. And there’s microbes at all these places and they’re heavily evolved. They see just free food, right? Except for the light at the end of the tunnel from a microbial point of view, that’s not good. But they’re busy digesting this food there. You’re feeding them, you’re watering them. And ironically, it’s actually really competitive for microbes to grow there. Like E. Coli, most people heard of this bacteria using a lab. It divides in the lab in 20 minutes. In the gut, it divides every 24 hours because it’s such competition with nutrients with all the other bugs there. So really, it’s a paste of these microbes there that are chewing on the food and stuff. And they divide and replicate and you poop some out and they continue to grow. And so you have this equilibrium of bugs in your gut. And this is what can do many different things in terms of influencing our health and disease.
Brett McKay : Yeah, the interesting thing that I learned from that is that there’s more microbes in our large intestine, in our colon, than there are in our stomach. I mean, there’s some in our stomach, not too many, because it’s too acidic in there.
Dr. Brett Finlay: Right, it’s very acidic.
Brett McKay : Then it increases a little bit as you get into the small intestine, but the colon, that’s where it’s…
Dr. Brett Finlay: That’s where it’s at.
Brett McKay : That’s where it’s at.
Dr. Brett Finlay: Right. They’re also producing things like neurotransmitters, the gut-brain axis, they influence the brain, for example. They’re chewing on these fibers, making a thing called short-chain fatty acids, which are wonderful anti-inflammatory molecules that are key for health and basically slow down aging. And they do a ton of different things. We haven’t figured them all out yet. There’s just an amazing number of genes in there, and they basically are doing a bunch of stuff. And they obviously make these small molecules, we call them metabolites, and these can then seep out of the gut and go into the body. And that’s how you can have a bug in the gut influencing somewhere else in the body, like the brain or the skin or something.
Brett McKay : So what health conditions are connected with poor gut microbiome health that we know of?
Dr. Brett Finlay: Well, the joke in the field is what aren’t. I mean, they all are. I mean, to give you an example, I think we use in the book, there’s a list of the top 10 reasons why a North American will die. And these are all the things you think about, like heart attacks and strokes and cardiovascular disease and lung disease and things. When you take the top 10, only one of those is actually a microbial infection, and that’s pneumonia. I think that was number eight. All these others are what we thought were traditional, just non-communicable diseases. It turns out that nine of those 10 actually have microbial associations. And the only one that doesn’t really have microbial association that we know of yet is accidents. You could argue that microbes influence behavior, which could cause accidents sort of thing. But all the others, like obesity, like type 2 diabetes, like heart attacks, like strokes, like chronic lung diseases, it’s called chronic COPD, for example, kidney diseases, these all have microbes that are now being associated with this. And bad microbes are actually being heavily associated with the disease. The slow part has been proving this is actually causing the disease.
Just because you have a disease, your microbes might be different, doesn’t mean it’s causing it. But more and more cases, we now realize microbes are actually contributing to that disease in quite significant ways.
Brett McKay : Well, and you talk about diseases of the gut in particular, like IBS, irritable bowel syndrome, ulcerative colitis. How does the microbiome affect those things?
Dr. Brett Finlay: Yeah, the gut diseases are pretty obvious to think about. Let’s take inflammatory bowel diseases, that’s ulcerative colitis. And basically what happens is people with these diseases, they have a genetic defect that basically they’re not able to fight off or block the bacteria from penetrating through the gut. So some of these inflammatory microbes get through and they then trigger the inflammation, which then causes inflammatory bowel disease, which is basically inflammation in the gut. So that’s fairly straightforward that basically the gut bugs are triggering inflammation, causing intestinal inflammation, causing these diseases. What’s less straightforward is say, for example, Alzheimer’s and dementia and Parkinson’s, for example, but gut microbes play a role in that. We know they play a major role in obesity. This is established many years ago when people could take feces from a fat mouse and put it in a thin mouse and it got fat. And they could take a fat mouse, put the feces in a thin mouse, it lost weight. And they could take feces from heavier set people, put it in mice, they would then gain weight. Unfortunately, we haven’t narrowed it down to say, “Well, here’s the perfect lean bug, for example, have this bug and you’ll be fine.” And of course, it’s linked to diet, but we now know that obesity, which is also a precursor to type 2 diabetes, is heavily linked with the gut microbiome composition.
Brett McKay : Yeah, with obesity, it seems like it’s both causation and correlation. So yeah, your microbes influence your weight, but your health habits influence your microbes. And I thought the transplanting microbes from an obese mouse into a non-obese mouse can actually cause weight gain was really interesting. There’s also a case study in humans where a woman who received a fecal transplant from her overweight daughter to treat some bacteria infection she had, that woman later gained significant weight and became obese herself. And she never struggled with her weight before the transplant. So when there is causation, is there a theory as to the mechanism? Why does that certain microbes make you more prone to be obese or overweight?
Dr. Brett Finlay: Yeah, the current theories, there’s basically the obese microbes are really, really good at harnessing energy out of any kind of food. So they generate a lot of energy for not much input. And ironically, the healthy ones chew on fiber stuff, they’re actually kind of, I was going to say crappy, but that’s probably the wrong point to use. They’re not very good at digesting the food. They don’t generate as many calories. So these obese microbes just generate calories like there’s no tomorrow because they think you’re starving or whatever. So they have to generate a lot of calories. So that’s the current thoughts, but it’s not proven. And I think there’s still a lot of discussion in that area.
Brett McKay : Let’s talk about another disease of the gut, colon cancer. This is an interesting one because one of my guilty pleasures is I check the Daily Mail, the tabloid from the United Kingdom. And one of their reoccurring things that always freaks me out is young people getting colon cancer. And I’m like, “Oh my gosh, what’s going on?” Because you hear about these stories of not only 50, 60-year-olds getting colon cancer, but 30-year-olds, 20-year-olds. And they have all these theories. It’s your microbiome and your diet is causing it. So what do we know about the role that the microbiome plays in colon cancer?
Dr. Brett Finlay: Yeah, I’m guessing that’s what the princess had, for example. I mean, you’re right. And this is really scary because we are seeing a real increase in 35-year-olds and things. Historically, it’s been an older one. Just last week, I had the lovely pleasure, because I’m getting older, of going through a colonoscopy. And I felt so sorry for my microbes because they must all be gone because you have to clear them all out to get scoped, for example. So what we think is going on is because of our, again, our Western diet and our unhealthy microbes, that they’re sort of constantly triggering inflammation in the gut. That’s causing tissue damage. And then when tissue is repaired, sometimes it’s repaired incorrectly. You can get a mutation, which can lead to cancer, for example. And so we think that the diet, the unhealthy diet, is associated with all this disruptions in the gut that has been leading to colon cancer. There’s also a microbe, a type of E. Coli being associated with it, but it’s not really fully proven yet, but it seems to be associated with it too. But I mean, one moral of this discussion is that if you’re young, don’t rule out getting screened for colon cancer.
If you have a family history of polyps or colon cancer, get the screen. I know it’s gross getting cleaned out for a day, but it could easily save your life. And just because you’re, I don’t know, 35, no longer means you’re immune to it. You could easily have it. So get screened. The good thing is that colon cancer takes a long time to present. It’s about a decade or so. So for example, mine, I was clean. So they said come back in five years. So if you get the polyps, which are precursors to colon cancer, you can actually then prevent the disease. And colon cancer is a horrible disease. So I know I’m preaching now, but this is something that I think that we didn’t really realize before. It’s really becoming prevalent among younger people, and this can be a lifesaving thing.
Brett McKay : We’re going to take a quick break for your words from our sponsors. And now back to the show. Okay. So we talked about gut health, the role that the microbiome plays in that. Let’s talk about the role the microbiome plays in our immune system. What’s going on there?
Dr. Brett Finlay: Everything.
Brett McKay : Okay. Yeah.
Dr. Brett Finlay: Yeah. This has been, I think, a real cornerstone of the whole microbiome field is what we realized is that even early in life, the microbes in the gut are influencing how your immune system developed. And we had some studies that we did in our lab, and we showed that we could actually predict whether kids would get asthma or not based on their microbiome at three months of age, because it would either push you towards an asthmatic allergic type reaction or a non-asthmatic thing based on the microbiome. And what we now realize is the microbiome is heavily programming the immune system to go the right way or the wrong way. And that’s why kids that are born, say, by C-section, they get the wrong microbes or antibiotics, the wrong microbes, they tend towards asthma and allergies because they don’t have the right microbes that are queuing their immune system up correctly. And then all through life, the microbes are tweaking the immune system, and it plays a really important role in this thing. And we talked a lot about fiber as being anti-inflammatory. And I’ll dive into this now. I mean, one of the key things about aging is this chronic inflammation.
Now, we know inflammation is good for fighting off infections and things. What we now realize is as you get older, two things happen. You get more inflammatory microbes, the bad ones, and your gut gets more permeable. And then these permeable bad microbes seep into the body. They trigger this low-grade inflammation. And it’s what we call inflammaging. And as I was writing the book, it was just scary because every aging process I looked at basically boils down to the same concept. Get older, microbes get bad, trigger inflammation, causes tissue damage, which then causes, and you can pretty much fill in every single one of the aging processes we see. And studies have been done in mice, not humans yet, that you could take feces from an old mouse, put it in a young mouse, it triggers inflammation, that mouse ages faster. And even better, if you take feces from a young mouse, put it in an old mouse, it slows down the aging process, less inflammation, and actually allows these mice to live longer. So maybe feces from a young person really is the fountain of youth. We don’t know that yet, but it plays a major role in the whole aging process.
Brett McKay : So you mentioned gut permeability. I’ve heard that phrase thrown around a lot and I kind of understand what it is, but what is that gut permeability?
Dr. Brett Finlay: Yeah, we already talked about the gut being a tube, right? Well, it’s not a polyethylene tube that nothing could get through. It has to be permeable because you have to get the nutrients from inside the gut into the body. So there’s a bunch of cells that make up the wall of this tube and they’re basically glued close together and they have specific ways of transporting stuff across that barrier. But in some cases, if you break the junctions between these cells, you basically cause a leak in the pipe. And really gut permeability is basically a leaky, porous type tube, pipe, whatever you want to call it, in the gut. And so things beyond molecules can seep through and with these holes in the gut, now microbes can actually seep through. And then the body’s immune system goes nuts when it sees these microbes because they shouldn’t be in the body. And that’s when you trigger the inflammation. So leaky gut, permeable gut is just, as it says, it’s basically your intestine is not as tight and as glued up as it should be.
Brett McKay : Okay. So an unhealthy gut microbiome can cause inflammaging because we have these microbiomes that cause inflammation. Are there microbiomes that actually strengthen our immune system that make it stronger and respond better?
Dr. Brett Finlay: Yeah, there’s a lot of studies started to come out. There’s some really neat studies on vaccine responses that good microbiome gives you a better vaccine response than bad, for example. And we know vaccine responses are going through the immune system. There’s really nice studies showing out the diet really does improve the immune system and it’s going through the microbiome. So following a Mediterranean diet, for example, there’s nice studies showing that actually does strengthen the immune system and makes it stronger and allows you to fight off infections and all the other things that the immune system does. So yeah, as to which bugs doing what, I think the details are still being filled in. We don’t have all the answers yet, but there’s no doubt this plays a big role in the immune system.
Brett McKay : Related to the immune system are autoimmune diseases where your immune system goes on overdrive and starts attacking healthy parts of your body, like a common one, rheumatoid arthritis or multiple sclerosis. Is there a connection between the microbiome and autoimmune diseases?
Dr. Brett Finlay: There is. People with those diseases have different microbes, more inflammatory as we’ve discussed. So there is a correlation, but I can’t tell you mechanistically how do they cause MS or rheumatoid arthritis. I mean, we know certain microbes associated with it. There’s very good predictions involved. Presumably these microbes are triggering inflammation stuff that causes the body to react with itself and cause these autoimmune diseases. So there’s correlation, but not causation yet.
Brett McKay : Not causation yet. Okay, let’s talk about brain health. So you mentioned some diseases that are connected to the microbiome. Alzheimer’s is one you mentioned earlier, but even depression, there’s like a connection or a correlation between the microbiome and depression. Talk about that. I think that was interesting.
Dr. Brett Finlay: Yeah, I mean, I think one of the most exciting areas in this field is what we call the gut-brain axis. How do the microbes influence the brain? Now, we know the brain influences the gut. There’s this nerve that goes down called the vagus nerve that influences gut motility and things. But now we realize that microbes are pulling up the other end of this nerve and they’re sending signals up to the brain. And just to give you some examples of how this all works is if you take an anxious, stressed, or depressed mouse or rat, do a fecal transfer into a normal mouse or rat, those normal mouse or rat now become anxious, stressed, or depressed just by transferring the microbes. There’s studies in the UK that have done big studies, looked at people using antibiotics. They are much more susceptible to anxiety, depression type thing. So there’s these microbial links there. And then the big ones in terms of mental aging diseases, of course, are Alzheimer’s and to a lesser extent Parkinson’s disease. These are two awful diseases. Alzheimer’s basically the type of dementia, but microbes seem to be involved in that probably because triggering the inflammation, triggering the tissue damage, triggering the brain damage.
And as we talk about in the book, that if you eat a healthy diet, something called the MIND diet, which is basically a modified Mediterranean diet, you can drop your incidence of Alzheimer’s disease by over 50%, which is just stunning in that sense. And work we’ve done in our own lab is that working on Parkinson’s disease, that’s a disease that causes tremors and you’re sort of stooped over and stuff. It’s about 1% of the population. And we showed that basically if people followed the MIND diet again, which is the Mediterranean diet, basically, that it delayed the onset of Parkinson’s in women by 17 years and by men by over a decade. And given that Parkinson’s doesn’t actually kick in until age 65 plus normally, you’re going to die of something else first. And we know this has got microbe related because we’ve done all the studies showing that gut microbes and Parkinson’s are different. And it all got started by cutting the nerve that hooks the gut to the brain, the vagus nerve. When you cut that, you have less levels of Parkinson’s. And so the way we think Parkinson’s actually works now is it starts in the gut.
And the biggest indication of getting Parkinson’s is constipation 30 years before you get it. And the second biggest risk factor is eating red meat. So these are both gut things, right? So we think basically you have a bad gut microbiome and it causes misfolding of this protein in the gut, something called alpha-synuclein, and that goes up the vagus nerve into the brain, the part of the brain that makes this dopamine, which suppresses tremors and things, and it destroys those cells. And then you start to see that the brain disease depression. So bottom line is prevent these diseases, eat a healthy diet. And I think that really bodes well for good brain health. There’s all sorts of research. Can we find a magic bug that decreases depression and stuff? Psychobiotic, you call these things. We don’t have these yet. There’s some hints of probiotics and things, but we don’t have good data yet. But that’s where this is all going. Can we actually influence the brain via gut microbes?
Brett McKay : Yeah. One thing I’ve seen, and this is all speculative, of course, but with depression, one thing I’ve seen thrown out there for, oh, here’s how you can help it, is eat resistant starch, like a food with resistant starch. And then I guess the gut microbiome breaks that down into the short chain fatty acid, particularly like butyrate. I think that’s how you, butyrate, yeah. The more butyrate you have, somehow that’s supposed to help stave off depression, I don’t know..
Dr. Brett Finlay: Good job, Brett. You turned into a scientist.
Brett McKay : I’m a scientist now. Yeah, I’m an expert.
Dr. Brett Finlay: Yeah. So fiber basically is broken down into what we call short chain fatty acids, and butyrate is the big one among these things. The joke is if you’re at a microbiome meeting, you want to know what the Wi-Fi password is, it’s probably butyrate because butyrate seems to be involved in absolutely everything. And butyrate is an anti-inflammatory molecule that decreases inflammation. And so the idea is that if you’re depressed, eating a better diet, you decrease the inflammation, hopefully decrease the symptoms associated with it. Ironically, it only gets boring. It all boils down mainly to diet and exercise. This is boring, I want the magic pill, right? Unfortunately, the magic pill is eat right, get some exercise, don’t stress, get a good night’s sleep, and enjoy life, really. But that doesn’t come in a pill form, so.
Brett McKay : Yeah, at the end of this conversation, we’ll talk about what you can do for your microbiome health, and it’ll be like, it’s basically a recap of what you’ve been saying throughout. Eat a good diet. But we’ll get into more specifics. You have some other interesting things there. Let’s talk about the microbiome in our mouth. So that’s the opening of that tube that goes through our body.
How does our microbiome in our mouth affect things like cavities or even bad breath?
Dr. Brett Finlay: Well, it drives both those things. I mean, ironically, the microbiome in the mouth is the earliest studied microbiome. There was a guy named Antonie van Leeuwenhoek in the late 1600s who invented the microscope, and he wanted to look at things. He looked at cool things like his sperm. But the other things he did is he swabbed out his mouth, and he made this most profound statement. There’s more animalcules, which we now know are bacteria, in his mouth than there are people living in the Netherlands, which is where he’s living at the time. Of course, no one believed this crazy guy seeing what you can have living things in, but ironically, that was, of course, the mouth microbiome. And your mouth is full of microbes. It’s a fun experiment. Swab it out, stain it, you’ll see all these microbes in there. And they do all sorts of things. Yes, some cause teeth cavities, so they chew away at the enamel of the teeth and then they bury into it, and that causes teeth cavities. One of the bigger problems is they cause inflammation of the gums around the teeth.
Whenever you go to the dentist, they say, “Floss your teeth.” Why are they telling you to floss your teeth, brush your teeth? Well, that’s because it’s for good gum health. And if you have crappy gum health, then it’s inflamed, there’s microbes living there, and also that allows the inflammatory microbes to seep into your body, and they get through these inflamed guts and then cause the problems associated with inflammation. And just to give you interesting examples that if you brush your teeth three times a day, you basically drop your Alzheimer’s rates by about 50%. You say, well, what does good oral health have to do with Alzheimer’s? And of course, the answer lies in the microbes that if you don’t brush your teeth, you have poor gum health, microbes seep through, they trigger inflammation, causes tissue damage, which then seems to be associated with Alzheimer’s disease.
Brett McKay : Yeah, whenever I go to the dentist, there’s next to the chair, they have this poster, and it’s got a body on there, and it points to all these things. If you don’t floss, here’s how it’s gonna affect, like one of them is heart disease. Like if you don’t floss and you get, you’re gonna have periodontal disease and you’re gonna have a heart attack. And I’m like, “Okay, I need to floss. I need to start flossing again.”
Dr. Brett Finlay: They’re guilty to get to it.
Brett McKay : And then my motivation lasts for like three weeks. And so yeah, what role does the mouth microbiome plays in heart disease? Is it the same sort of thing, just inflammation?
Dr. Brett Finlay: Same as we were discussing, these inflammatory type things, the inflation is hard on the heart, and then it could lead to these heart things because you allow the microbes to seep into the body. Because just like the gastrointestinal tract, the mouth is generally pretty impermeable, allowing bugs into the body, unless you have poor gum health, and then that’s a ticket for all these oral microbes to then seep into the body and trigger these problems. So yeah, it’s an interesting way of guilting you into flossing your teeth and stuff. But it’s actually good for you, that’s why is the good gum health.
Brett McKay : One thing you mentioned in the book as kind of an aside but inspired me to go try this out, probiotic gum for oral health. Is there anything to that?
Dr. Brett Finlay: There’s some, I mean, every time you go and get your teeth cleaned, especially if they do what’s called an acid wash, they, they just destroy all the microbes in and on your teeth, the reason you’re getting teeth cleaned, all that plaque, all that white stuff they chip off. But they’re called extracellular polysaccharides. They’re carbohydrates, they’re sugars basically that these microbes produce and they build this basically impermeable wall around them and that’s when they’re chipping off the plaque. But every time you get your teeth cleaned they strip it down to nothing. And it’s really interesting as to which bug adheres first. That sets up the hierarchy of who’s gonna then come next and depending who it adheres first that it dictates who’s come second and third and stuff. So this probiotic gum seems to actually help establish getting good microbes down first. So they set up the rules, okay, we’re gonna be a good colon here, we’re gonna build these microbial skyscrapers based on this as opposed to based on say a pathogen. So there’s some data on the probiotic gum. Much like all probiotics, it’s not that great data yet, but there’s some there. And so yeah, how did it taste?
Brett McKay : It was okay. I mean, it tasted like gum. It was kind of, it was a little chalky.
Dr. Brett Finlay: Yeah, eating microbes.
Brett McKay : Yeah, eating microbes. We’ll talk more about probiotics here because I think that’s interesting. But let’s talk about one more thing, the microbiome on our skin. I’ve been seeing more about this in advertisements with skincare products. They talk about, “Oh, this is good for your microbiome on your skin.” So what does the microbiome on our skin do?
Dr. Brett Finlay: Yeah, well, like I said, you have microbes coated all your skin and wet areas, there’s more microbes, but each place on your skin has a certain microbial collection, and your right hand is going to be very different than your left hand because they do different things, they touch different things, and that’s normal. But one of the biggest things they do is they fight off, they basically hog all the sites that a pathogen could bind to, so skin effects and stuff are less in people with healthy microbiomes. They also seem to be helping with skin health and you know that as a teenager when you get pimples for example, that’s because a bacterium is chewing on the oil your face makes as a teenager and that then generates some acne and pimples for example. There’s interesting stuff coming out on probiotics and skin health, it’s not perfect but I think there’s some interesting data coming out that you can actually put microbes in skin creams and then may enhance your skin health type thing. And not just skin microbes, gut microbes. There’s lots of studies coming out showing that if you have healthy gut microbe it actually improves your skin health and helps decrease radiation damage when you get sunburned for example.
Both the skin and the gut microbes seem to decrease the skin damage that ultimately results in wrinkles and your skin collapsing as you get older and all the skin things associated with aging. So yeah, the cosmetic industry is certainly capitalizing on this. They kind of take it too far in my opinion sometimes but there is some interesting stuff coming out that you can actually put microbes in skin creams and then may enhance your skin health type thing.
Brett McKay : Yeah, I mean one thing that you speculated on is that maybe you could bank your microbiomes, your skin microbiome when you’re like 20 so that when you’re in your 60s you can like apply it on your face to maintain your youthful looks.
Dr. Brett Finlay: Sheer speculation but we know that the microbes on your skin at 60 are different than those at 20 and are they doing this? I don’t know. And they’ve done experiments in mice and other things and even in people where they take older people microbes put them on younger people seems to cause poor skin health and vice versa kind of thing. So yeah, maybe there’s hope. We all want to look good forever but maybe this could help.
Brett McKay : I thought it was interesting too. Just kind of my mind was blown when I heard about this. Speaking of our microbiome on our skin system one that’s most exposed to our environment, but you talked about how every one of us has our own unique microbiome. We all have a different one and you could go into like a hotel room and your microbiome will just like populate that entire hotel room. You can tell like, “Okay, this family was in this hotel room just by measuring the microbiome like on the TV remote control.”
Dr. Brett Finlay: Yep, you can.
Brett McKay : Yeah, then another family comes in and like that microbiome just colonizes and takes over.
Dr. Brett Finlay: Takes over. Yeah, I mean changing the sheets isn’t enough. It’s just the way it is. We slough skin cells. We also slough microbes and you can easily see the microbial signatures of people. And as you say, they change over as the people change over. There’s nothing wrong with it. It’s just biology in action. It’s what it is. And like it’s not associated with getting infected with someone because the people before you had some microbe. It’s just the way it is. It’s just biology.
Brett McKay : Okay, let’s talk about nurturing a healthy microbiome because I’m sure this is the thing that people want to, this is what they’re listening to. Like what can I do to have a healthy microbiome? And we’ve mentioned some things already, but the diet sounds like just eat a well-balanced diet, particularly a lot of fiber because your gut microbiome needs that. Is that pretty much it?
Dr. Brett Finlay: Yeah, so diet is first and foremost the biggest thing that affects at least especially your gut microbiome. And the more plant fiber you eat, the better off you’re going to be. You want to decrease red meat. You can probably have it once in a while, but you should not be eating red meat regularly. That’s not good for the microbiome. And of course, stay away from processed foods, including things like white sugar, white flour. Always go for the whole grains. And sort of the saying is, you know, walk around the outside of the grocery store and stay away from the middle because the middle is all the processed foods. There’s nothing good for microbes in there whatsoever. And you want to stick to the produce counters and stuff like that. So diet is first and foremost the biggest one.
Brett McKay : What about fermented foods? Because that’s food that has bacteria in it. Does that have a benefit?
Dr. Brett Finlay: It does. Kimchi. During COVID, I worked on becoming a sourdough bread maker kind of thing because everyone did. And, you know, I thought, well, sourdough bread, it’s cooked, right? So is it probiotic or not? And it turns out that it’s actually good for you because of all the microbial products that are in that cooked bread and they’ve broken down the things in a beneficial way. But yeah, all fermented foods are generally speaking, they’re quite good for you and definitely embrace those.
Brett McKay : Yeah, I eat, part of my routine is I have, with breakfast, I have like a scoop of kimchi.
Dr. Brett Finlay: Excellent. Or sauerkraut or anything like that.
Brett McKay : Sauerkraut, I love sauerkraut. And then I eat yogurt. I like Greek yogurt is another thing I eat. What about mentioning probiotics? Because we typically think, okay, eat yogurt because it has probiotics, eat kimchi has probiotics. Probiotic supplements, you’re seeing advertisements for this all the time. Do probiotics actually do anything for us? Like the supplement types?
Dr. Brett Finlay: Yeah, this is a hard one. Bottom line is a probiotic, basically, it’s not going to hurt you. But the real argument is, is it good for you? And there are some probiotics that are proven in clinical trials for some clinical indications. There are some probiotics that can be used for, say, antibiotic-associated diarrhea, take antibiotic diarrhea, some work there. There’s yeast that’s associated with decreasing clostridium difficile infections. The analogy I like to use is that you need a new pair of runners. You walk into a running shoe store and there’s this wall full of runners. There’s joggers and hikers and basketball shoes and tennis shoes and whatever. You don’t just grab the cheapest pair and walk out. And same with probiotics. You just Google the word probiotic chart, and there’s one for both US and one for Canada. And there it lists what all the probiotics are and what is the clinical evidence they will do something for a particular disease. Now, there’s no probiotics that have been proven to basically make you feel better because that’s clinically a really tough endpoint and no company’s ever going to want to do that. So there’s some that work, but really, they’re quite few and the clinical evidence is very poor.
They’re not like night and day, like an antibiotic treatment is just night and day for curing an infection. But all that said, I’m really hopeful for the future we’ll get into these worlds where we’re adding eight, ten microbes and it’ll have a defined biochemical outcome. They’ll be taking that as a drug, really. It’s gone through the clinical trials, and there’s several that are now coming down the pipes of exactly this, where you get a prescription from a doctor for this mix of microbes to actually do this. And I call that probiotics 2.0 or next-gen probiotics. I think that’s where the real excitement is coming.
Brett McKay : Okay, so it sounds like take one if you want. It’s probably not going to do much for you. It’s not going to hurt you, but it sounds like you’re probably going to get more bang for your buck focusing on the prebiotics, like eating the fiber food that gives your microbiome stuff to munch on.
Dr. Brett Finlay: Yeah, I mean, there’s three classifications. There’s probiotics, which are basically live microbes, and they tell you how many microbes are alive when you take this thing. The problem is that they pretty much die as soon as they go inside you. I mean, for example, lactobacillus is a microbe from the vagina, which is a very different world than the gut. And you swallow this lactobacillus, vagina’s got air and it’s acidic pH, the gut has no air and it’s a basic pH. So these things just die. So that’s why you have to take them every day. It’s a great marketing point of view because you have to take this every day, but you’re just basically taking a microbial goo kind of thing. So the new mixtures will be microbes from the gut and for the gut that will actually then take that and actually set up a colony and live in the gut. And it’s not such a great marketing design because ideally, if it works, you should only have to take it and then you won’t have to take it again. But that’s where we’re heading with these things.
Brett McKay : Gotcha. What about any activities? You talked about let them eat dirt. We want your kids out there playing in the mud. As an adult, should we be doing the same thing, getting out in nature and possibly making mud pies?
Dr. Brett Finlay: Absolutely. Yeah, especially if you’re going to insult your microbes, you have to take antibiotics for an infection. How do you fix them? There’s no mix of microbes you can actually just take right now to make your microbes good. The best way is eat healthy and get outside and embrace microbes, let your dog lick you in the face, for example, all these kinds of things that generate microbes. I mean, you take eldercare homes, you think how we treat people in there. I mean, I personally think there should be dogs and little kids running through these places and let them defecate all over the place and that’s how you’re going to get these young microbes into the elderly as opposed to the crustless white sandwiches and don’t let anyone in kind of thing. I mean, that’s a terrible way from a microbe point of view to live. So embrace your microbes and then doing that, that’ll actually improve your health.
Brett McKay : And then also don’t be so sanitary inside your house. Be sanitary, but don’t take it to an extreme.
Dr. Brett Finlay: Yeah, if you’ve got mold growing and stuff, that’s probably not a good idea, but don’t worry if a hunk of food falls on the floor, it’s just fine. It’s not, you know, unless it lands in a pile of mold or something, it’s fine. So yeah, it’s this balance of hygiene and stuff. I mean, other proactive things. So we talked about diet. I mean, exercise is really important. Exercise really decreases the inflammatory microbes and pushes your microbes toward more anti-inflammatory type thing. And all the studies show that we know exercise is good for us. It’s actually really good for your microbes too, which is part of the reason why exercise is good for us. So you want the exercise and you don’t have to be a marathon runner, but just, you know, even daily walking and things has a massive effect on the microbes. You want to get a good night’s sleep. Diet has a big effect on microbes that allow you to sleep better type things. So there’s good sleep. The one we have the most problem with in our society, I think, is stress. And we live in a very stressful world.
I mean, even when I sit there all day, my watch says you have had a stressful day. You should relax now. It drives me nuts. But stress has a terrible effect on your microbes. Again, driving them towards the pro-inflammatory type thing and basically making them bad microbes again. And the final thing is community. And this is one thing we tend not to embrace so much is that community is really important. And that’s probably because it’s microbial swapping. There’s a cool study that could tell who played cards with who based on their microbial composition. So you’re swapping microbes with your friends kind of thing. So I jokingly say maybe dating apps should have a microbiome screen so that you can, you know, who are you dating and what are your microbes? I don’t know yet.
Brett McKay : Okay, so to have a healthy microbiome, you want to avoid processed foods, eat more fiber, maybe some fermented foods, exercise that decreases inflammatory microbes, de-stress, don’t be overly scrupulous about hygiene. You recommend not using antibacterial soap unless absolutely necessary because just plain old soap and water works, is fine in most cases. Sleep is also another component to a healthy microbiome. There’s a two-way relationship there. Good sleep supports a healthy diverse microbiome, while disrupted sleep can start just kind of throw things out of whack in your gut. And then in turn, the gut microbiome can help regulate sleep-related hormones like melatonin, GABA, serotonin. So that means a healthier microbiome can lead to better sleep or support better sleep. And then hang out with people. Diversify your microbiome by getting in contact with other people’s microbiomes. And then another thing I think is just be judicious with antibiotic use. So if your doctor prescribes you antibiotics, you can ask, do I really need to take antibiotics?
Dr. Brett Finlay: Yeah, I mean, historically we sort of said, “Well, antibiotics can’t hurt. Take them anyway.” I mean, kids with otitis media, with ear infections, they get prescribed antibiotics all the time. Well, that’s often a viral infection and antibiotics not going to do anything. And there’s two reasons why you want to avoid antibiotics. One is the increase in the antimicrobial resistance, which is a huge issue. Bugs get resistant to it. But secondly, now it has a really carpet bomb for microbiome. So if you have a life-threatening disease that antibiotics are needed, absolutely take it. But if it’s something that might not work or whatever, I think there’s still the lack of realization out there that they do have these secondary effects. And people take antibiotics are much more prone to obese, have high levels of asthma, have mental diseases. There’s all these studies coming out now showing that long-term multiple antibiotic use is really just not good for you because it impacts your microbiome.
Brett McKay : Well, Brett, this has been a great conversation. I think we understand the microbiome now. Where can people go to learn more about the book and your work?
Dr. Brett Finlay: Well, it’s called The Microbiome Master Key: Harness Your Microbes to Unlock Whole Body Health, Lifetime Vitality. It’s available on Amazon, et cetera. You can Google me. We have a lab webpage and thing about our work. And also, like I said, if you have kids, look up Let Them Eat Dirt or watch the YouTube video of the documentary on that thing. I guess I just urge people to think about how we live and to embrace the microbes as part of our living. And you scroll through the news and stuff. It’s all about exercise and things, but why is that good for us? And we now realize that a major component of that is the microbes. And the good thing is you can change your microbes. You can’t change your genes, but you can change your microbes. So if we can change our microbes, there’s actually hope for fixing things and basically pushing more towards a health and vital type aging process. So that’s the idea of all this.
Brett McKay : Fantastic. Well, Brett Finley, thanks for your time. It’s been a pleasure.
Dr. Brett Finlay: Thanks a lot, Brett.
Brett McKay : My guest today was Dr. Brett Finley. He’s the co-author of the book, The Microbiome Master Key. It’s available on amazon.com and bookstores everywhere. Check out our show notes at aom.is/microbiome. You can find links to resources and delve deeper into this topic. Well, that wraps up another edition of the AOM Podcast. Make sure to check out our website at artofmanliness.com where you can find our podcast archives and make sure to check out our new newsletter. It’s called Dying Breed. You can sign up at dyingbreed.net. It’s a great way to support the show directly. As always, thank you for the continued support. Until next time, this is Brett McKay reminding you to listen to the AOM Podcast, but put what you’ve heard into action.
