The Microbiome Master Key — How 100 Trillion Bacteria Influence Your Weight, Mood, and All-Around Health
Episode Stats
Summary
Dr. Brett Finlay is a microbiologist and the co-author of The Microbiome Master Key. In this episode, Dr. Finlay 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 9 of the top 10 leading causes of death, as well as everything from depression to Parkinson s.
Transcript
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Brett McKay here, and welcome to another edition of the Art of Manliness podcast.
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When you think of the microbiome, you probably think of your gut, but bacteria live all over
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your body, and they're incredibly numerous. You play host to about as many microbes,
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100 trillion of them, as you do human cells. As my guest will explain, these microbial ecosystems
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are not only ubiquitous, but hugely influential for your health, impacting everything from your
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weight and mood to your risk of developing many diseases. Dr. Brett Finlay is a microbiologist
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and the co-author of The Microbiome Master Key. Today on the show, Brett explains what the microbiome is,
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how modern life, including our overemphasis on hygiene, has damaged it, and how the quality
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of your microbiome is connected to nine of the top 10 leading causes of death, as well as everything
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from depression to Parkinson's. Brett also shares how we can boost the health of our microbiome,
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including whether probiotic supplements are effective, how something as simple as flossing
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your teeth can cut your risk of Alzheimer's by 50%, and why you might want to let your dog lick
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you in the face. After the show's over, check out our show notes at aom.is slash microbiome.
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So you are a microbiologist and you study how microbes can cause disease in us, but also you've
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done a lot of writing and research and education on our microbiome that we all have inside of us,
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on us. We'll talk about that as well. I'm sure a lot of people have heard of the microbiome. They
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may be seeing advertisements for supplements or even food that's supposed to help your microbiome.
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But I imagine if you asked a lot of people, like, what is the microbiome? And they'd be like, oh,
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kind of hem and haw. So let's start with this question. What is the microbiome?
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That's a good question. Basically, it's a collection of all the microbes living in and
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on you. So most of the time we think about bacteria, just because they've been easier
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to study, but it also includes viruses, includes eukaryotic proteases, single cell, things like
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yeast, for example. So really, it's the collection of all the microbes that are living in and on us,
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and they're all invisible to the eye, but there's lots of them there.
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Okay. And you said in the book that we are more microbial than human. What do you mean by that?
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I don't mean to insult anyone, but so basically, there's a similar number of human cells in us
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as there are bacteria. So they're about one to one. So there's many bacteria living in and on you
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as there are human cells. And these bacteria encored about 100 times more genes than the homo sapien
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genome. So you put two of those things together. I love to tell my students that they're more
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microbial than human, just because there's so many of these microbes in and on us.
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So give us like a number, like a rough estimate. Like what would that look like?
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Yeah, it's about 100 trillion. What does that mean?
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Well, let's talk graphics here. If you take a piece of feces the size of your fingertip,
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I know it's a gross analogy, but hang in there. There are more microbes in that piece of feces
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than there are humans living on the entire planet. So I jokingly say, think of the genocide,
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you know, every time you flush the toilet kind of thing. There's a lot of them on it.
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I mean, if you were able to clump all this into one mass, like how much would that weigh,
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like how much of our body weigh would be microbes?
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Yeah, it's about three or four pounds. So we kind of think the microbiome is sort of another organ.
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It's about the size of your heart, for example, collectively, but they're dispersed. Most of them
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are in the gut, the lower gut, but they're also all over many other parts of our body as well.
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Yeah, because I think most people, when we think of the microbiome, they're thinking of,
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we'll talk about this idea of gut health. But as you said, it's other places besides our guts.
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Right. I mean, the gut's the most obvious and basically the bacteria get more and more numerous
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as you go down the gastrointestinal tract. And they're the most right near the very bottom in
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what's called the large colon, the large intestine. And that's kind of really a paste of bacteria.
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And there's 10 to the 8th, 10 to the 9th bacteria per gram of feces there. Phenomenal numbers.
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Now, bacteria aren't in us. So generally the blood and inside our body is generally considered
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sterile unless it's infected, but they're basically on us. So wherever our body is exposed to the
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outside. So on your skin, for example, and like all living organisms, they like moisture. So there's
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more microbes in your armpits and groin than there is, say, on your forearms. They're in your mouth and
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the upper nasal tract. They're in the urinary tract, especially in women. And so basically wherever
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your body is exposed to the outside, there's microbes that are there, kind of serving as this
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An interesting point you made in the book, and I had to think about this, and I was like, that makes
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sense. We typically think of our gut as the inside of us, but technically it's the outside.
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It's a tube running through us. That's right. It's really outside. It's just this one open tube that
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goes from the mouth to the anus and there's lots of microbes in there.
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Yeah. I had to think about that for a little bit. Oh yeah, it is. It is on the outside.
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It's the outside going sort of like a hole through us.
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So, okay, the microbiome, it's bacteria, it's fungus, it's yeast, it can be viruses,
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but not all of these microbes cause sickness or illness. So like, what's the difference between,
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let's say, the bacteria that causes us to get the stomach flu compared to the bacteria that's just
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always there and not doing anything to us, or maybe actually doing good stuff to us?
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Yeah. I mean, the history of microbiology is focused on bacteria that cause disease,
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called these infectious diseases. So that's, you know, salmonella causing typhoid fever,
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that's listeria causing meningitis. But there's only about a hundred types of bacteria that can
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actually cause disease in humans. Yet we have thousands and thousands of microbial species living
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in and on us. And these are just basically normal residents under normal situations. They don't cause
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any problems. And we're now realizing they're actually beneficial there. And so there's kind
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of these two camps, those that cause disease and those that just sort of live on us and
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really symbiotically and are actually beneficial for us. And so, yeah, we've historically focused
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on the bad guys, but ironically, we're now starting to focus on the good guys and realize they actually
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have a large role to play in our general health and well-being.
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Okay. Okay. So how does this bacteria get on us? Like, where does it come from?
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Well, there's bacteria everywhere. You can't see them, but they're everywhere. I mean, I
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jokingly say the world is coated in a veneer of feces and microbes. The soil is full of microbes,
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for example. And every food you eat, there's microbes in there until you cook them. They're
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alive until you cook them. And every time you put your hand in your mouth, for example,
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you're introducing microbes. I'm like, there's microbes all over your cell phone. They're all
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over the toilet seat. They're all over the world. And it's a gross concept when you think about it,
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but they're just there and this is normal and they're everywhere.
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And then you also talk about throughout our lifespan, we get kind of hit with these microbes
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in a healthy way. And like, it happens at the very beginning of life. Like once you're born,
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that's when you get hit with a lot of these microbes that are potentially good for you.
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Yes, that's right. I mean, I did write another book called Let Them Eat Dirt. We talk all about
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how important this early life microbes is, and they really are important for development.
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Generally, the fetus, so it's not born yet, is sterile, as far as we know. There are some
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microbial signatures we haven't shown. There's live microbes in there. But the second you're born,
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I mean, think about birth. It's a very messy business. But ironically, that first big gulp you
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take, it's full of vaginal fluids, feces, all these other horrible things. But these are full of
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microbes. And ironically, that's really good for the baby and really important. So as soon as you're
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born, you get microbes. And anyone that's, you know, has a breastfeed kid, you know, the feces is
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quite sweet smelling and stuff. But the second you introduce solid foods, it becomes very different
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story because the microbes have now changed. And generally, once you're through adolescence,
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you're pretty much entire adult life, your microbiome is pretty constant, doesn't really
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change unless you do something drastic, like move or go into antibiotics or change diets.
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And then as you age, post 65, the microbes do shift. And that seems to create some of the
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Let's talk about that one book you wrote, Let Them Eat Dirt. Because I remember when that came out,
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I think someone wrote an article for our website, you know, and they cited that book. But the importance
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of your kids playing in the dirt, getting out in nature, playing in mud, et cetera. Why is that so
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It's really important. It's become more important. And I urge your listeners to go to YouTube
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and look up Let Them Eat Dirt. We have a nice one hour documentary instead of, you don't have to
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read the whole book. But what happens is these early life microbes, they basically help program
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our body. We know that we're going to be born into a microbial world. So they play a major role
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in developing our immune system. And this can determine whether you get asthma or not, for example.
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They play a big role in obesity. They help our gut develop. They help our brain develop.
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We know that animals don't have microbes. They don't develop normally. You need these microbes
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a part of us. So when you think of how we lived as a species for millions of years, we were just
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outside in lots of microbes everywhere. This is actually an important part of us. So in these days,
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when a kid is born by a sterile cesarean section and then stays in a sterile apartment, doesn't get
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outside and stuff, you're actually depriving the kid of the normal microbes that they need for the
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normal development. And then we see the appearance of these diseases such as asthma and obesity and
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things that are associated with an imbalanced microbiome early in life.
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All right. And hopefully we can talk about the role the microbiome plays in things like obesity here
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and the rest of our conversation. Because you dig into that, particularly how it can influence
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obesity as we get older. This is what this book's about. The Microbiome Master Key is about
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the microbiome past childhood, like when you're in your 30s, 40s, and then beyond.
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So what does a healthy microbiome look like? And I imagine it's going to look different in different
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parts of the body. Yeah, that's actually a really hard question to answer. For years, we struggled.
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We're really good at saying what a non-healthy microbiome looks like. We could tell you pretty
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quickly, oh, you're going to head towards inflammatory bowel disease or Parkinson's or whatever.
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But we actually really struggle. What is a good microbiome? Basically, it's a very diverse
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ecosystem. We all know that diversity in ecosystems are really important. You want lots of microbial
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species there. Generally speaking, from the gut point of view, you want microbes that are good at
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digesting fiber, because that is a very beneficial effect for us and as for the microbiome. And you
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don't want microbes that are generally associated with inflammation. So these are microbes that,
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I'll talk technical for a sec there, have something called lipopolysaccharide, which is a highly
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inflammatory molecule. And it basically excites the host immune system and causes unwanted inflammation.
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And that's a cornerstone to unbalanced microbiome. But there is no one perfect microbiome. You're
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right. Not only each person has a unique set of microbes, so there's no one conserved microbe in all
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people across the world. Different areas of the world have different microbiomes. Different parts of the
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body have different microbiomes. So yeah, we struggle with saying, okay, this is the perfect, this is what you
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should head for kind of thing. We know what's bad, but we have trouble saying what's good.
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Yeah, well, the bad ones are basically the increase in these inflammatory microbes and decrease in the
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short-chain fatty acid. I mean, the fiber fermenters, for example, that is generally bad. And that actually
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generally also kicks in later in life when you shift towards a more detrimental type microbiome.
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If you're eating a highly processed food diet, lots of white sugar, white flour, all the stuff that we love
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to eat, that ironically is actually bad for your microbiome because it's already broken down. So you're
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really starving the fiber digesting microbes down in your body. So that actually contributes to
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problems like obesity and other type 2 diabetes and other issues.
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So something I've seen, I'm sure people have seen this as well. They're like, well, I want to figure
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out what my microbiome is like because I want to optimize. Everyone's about optimizing their health.
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And so there's tests you can take where you actually, you poop and then you like swab your poop and
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then you mail it. And then these companies can tell you, oh, well, here's, you have a healthy
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microbiome. You have an unhealthy. Is there anything to that? Do these tests actually tell
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Really clinically? No, there's nothing clinical done yet. These companies say you should do it
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every few weeks so we can tell you what you're doing and stuff. It gives you a general idea.
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If you're a real nerd and want to know what's in you, it's really cool. If you're a microbiologist,
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number of species names, it's really fun to put up in a post on your wall. But really it's not,
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there's no clinical indications that you could say, okay, based on this, I should do that kind of thing.
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So right now it's a general interest thing, but it's really not a medically proven test,
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Okay. So it might be a great, like dirty Santa Christmas.
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It's fun. It's just like, yeah, it's something fun.
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Hey dad, you want to know what's in your poop? Here we go.
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Sure. You get your genome sequenced and you're 2% Neanderthal. You get your microbiome sequenced
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and you've got some bacteroidetes and all these, all the cool things in there. And, but what do you do
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with that? The problem is what you do with that. And right now we're lacking the information,
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to say, based on this composition, you should do this. Yeah. So that's where we stand.
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Are there moves to make these tests more useful? I mean, is that something companies and researchers
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They're thinking about it. And one thing we can say is that, you know, you can predict
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many diseases based on the microbiome composition. Like you can tell if a person is obese just by
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the microbiome. We have some work showing that we can predict whether someone has Parkinson's or
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not based on the microbiome. But then knowing that, say, okay, what do I do to fix it? And that's
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where the difficulty comes. The problem is standardizing it, making a universal test. And
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so it's been difficult. So like I say, right now, there's no clinical test you can get done for the
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So something people might've heard, and you talk about this in the book, and you mentioned this
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earlier too, how we're raising kids these days where they're not exposed to microbes. We keep
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everything very sterile and clean. It's having effects. How has modern life disrupted our
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Yeah. The easiest thought experiment is to think, how did we live, I don't know, 10,000,
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100,000 years ago versus how we live now? I mean, historically, we were heavily in contact
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with our environment at all times. It was a dirty environment. And we obviously got a lot of
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microbes. We also died of infectious diseases very early. But then, you know, when we started to
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realize that germs cause disease, society about 120 years ago went on a major hygiene campaign.
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So let's clean the world up. Let's bring in hygiene. Let's bring in hand washing, hand sanitizer.
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Antibiotics were invented. So we really cleaned the world up. And that had a spectacular effect
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on decreasing infectious diseases. I mean, it used to be that, you know, most of your kids would die
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in childhood. Now, very kids, very few kids die in developed countries of disease. But what we now
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realize is that, oops, maybe we cleaned the world up too much. And the collateral
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damage of getting rid of all microbes, we now realize that some of these are beneficial.
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So antibiotic use is a major issue associated with microbiome disruption. Hygiene, as we've
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talked about already, is a big thing. I mean, if you think how kids are raised these days,
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when's the last time they got to roll in the dirt and get dirty and everything? Oh, no,
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you'll get dirty. And COVID, of course, really set us back because we went back to more of a hygiene
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type world. But we've been trying to push for a trend that we need a balance between if it's
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potentially infectious, stay away. But if it's potentially not infectious, embrace the microbes.
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And that's where the conflict lies. And pretty much all of modern life is around sanitation.
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I mean, think how we design buildings. We, you know, get an airplane seat, we wipe it down with
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an ethanol swab. You know, we wear masks all the time now. The world has really changed to be hygienic.
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It's good for infectious disease. It's terrible for your microbiome.
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And besides the hygiene aspect, as you mentioned earlier, diet. Our diet
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has become more standardized, highly processed, and that's not good for the microbiome as well.
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No, that is not good at all. I mean, you think how ancestors ate, they were chewing on nuts and
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fiber and plant stuff and things. And we don't do that anymore. We have the nice processed foods.
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And the problem is, like I said, they're already broken down. So let's see, we had to stick a celery,
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for example, that's full of fiber. We don't have the enzymes to break down fiber, microbes do. So
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the body relies on it going to the large intestine, where the microbes will chew away in the fiber.
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And ironically, that's beneficial because the products of this fiber are anti-inflammatory.
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They help the body grow and things. If you're eating white sugar and white flour and traditional
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Western diet, it's already broken down. And really, there's nothing for the microbes to do.
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So ironically, most of it gets absorbed in the upper small intestine and doesn't even make it down
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to large intestine. So you're kind of starving your microbes there.
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Yeah, I think the key is that our processed diets that we have, it's making our microbiome
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in our gut particularly less diverse. And it's not just an individual issue. It could potentially
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be a generational one. I think you said in the book that when people eat a low fiber,
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highly processed diet, they lose certain gut bacteria, and then they pass on a less diverse
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microbiome to their children. And you kind of make the argument that if we don't change
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our diet, we could, for example, lose the bacteria that we need to digest fiber.
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Yeah, the studies have shown that, you know, in my studies, if you deprive them of fiber for
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about four generations, you can't go back. And many of us microbiologists are concerned that
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we've evolved with all these microbes over the millennia, and suddenly we're taking them
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out of our evolutionary equation. We're worried that, you know, a generation or two from now
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will suddenly wake up and realize, oh no, we're missing these key microbes that basically
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make us human. And what do we do about it? So there's even biobanking going on now trying
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to preserve some of these and some of the uncontacted civilizations around the world and
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trying to preserve it. But yes, there's a real concern that there's these missing microbes
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that generation after generation, we're basically getting less and less diverse and we're losing
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all the microbes that we need. And the worry is that we're going to put ourselves in a position
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where suddenly we can't go back. And that's really scary.
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All right. So modern life has disrupted microbiomes because we're too hygienic. You know, you're
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not saying hygiene is not good, but like taking it to the extreme is not good. Antibiotics
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are a great thing. It's saved a lot of lives, but if you just use it for anything, that's
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not good because you kill the good bacteria or, and you even make the bad bacteria resistant
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to the antibiotics, they become less useful. And then also just our diet is messing that up.
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Well, so let's talk about some of the potential health consequences of not having a healthy
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microbiome, of having an unhealthy one. Let's talk about the mecca of microbes is what you
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call this area, the gut. What makes up our gut exactly?
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Yeah. I mean, gut is obviously where you digest food. You chew it. It goes down to the stomach,
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then onto the small bowel and the large bowel. And there's microbes at all these places and
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they're heavily evolved. I mean, they see it as free food, right? Except for the light at the
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end of the tunnel. From a microbial point of view, that's not good, but they're busy digesting
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this food there. You're feeding them, you're watering them. And ironically, it's actually
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really competitive for microbes to grow there. Like E. coli, most people heard of this bacteria
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using a lab. It divides in lab in 20 minutes. In the gut, it divides every 24 hours because it's
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in such competition with nutrients, with all the other bugs there. So really it's a paste of these
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microbes there that are chewing on the food and stuff and they divide and replicate and you poop some
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out and they continue to grow. And so you have this equilibrium of bugs in your gut. And this is
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what can do many different things in terms of influencing our health and disease.
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Yeah. The interesting thing that I learned from that is that there's more microbes in our large
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intestine, in our colon, than there are in our stomach. I mean, there's some in our stomach,
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Then it increases a little bit as you get into the small intestine, but the colon, that's where it's...
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They're also producing things like neurotransmitters. They got brain access. They
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influence the brain, for example. They're chewing on these fibers, making a thing called short-chain
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fatty acids, which are wonderful anti-inflammatory molecules that are key for health and basically
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slow down aging. And they do a ton of different things. We haven't figured them all out yet.
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There's just an amazing number of genes in there and they basically are doing a bunch of stuff.
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And they obviously make these small molecules, we call them metabolites. And these can then
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seep out of the gut to go into the body. And that's how you can have a bug in the gut
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influencing somewhere else in the body, like the brain and the skin or something.
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So what health conditions are connected with poor gut microbiome health that we know of?
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Well, the joke in the field is what aren't. I mean, they all are. So, I mean, to give you an
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example, there's what I think we use in the book, there's a list of the top 10 reasons why
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a North American will die. And these are all the things you think about, like heart attacks and
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strokes and cardiovascular disease and lung disease and things. When you take the top
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10, only one of those is actually a microbial infection. That's pneumonia. I think that was
00:20:49.320
number eight. All these others are what we thought were traditional, just, you know, non-communicable
00:20:54.540
diseases. It turns out that nine of those 10 actually have microbial associations. And the only one that
00:21:01.460
doesn't really have microbial association that we know of yet is accidents. You could argue that
00:21:06.760
microbes influence behavior, which could cause aconus sort of thing. But all the others, like obesity,
00:21:12.360
like type 2 diabetes, like heart attacks, like strokes, like chronic lung diseases, called chronic
00:21:18.360
COPD, for example, kidney diseases, these all have microbes that are now being associated with this. And
00:21:24.700
bad microbes are actually being heavily associated with the disease. The slow part has been proving
00:21:29.900
this is actually causing the disease. Just because you have a disease, your microbes might be different,
00:21:34.360
doesn't mean it's causing it. But more and more cases, we now realize the microbes are actually
00:21:38.060
contributed to that disease in quite significant ways.
00:21:40.920
Well, and you have, you talk about diseases of the gut in particular, like IBS, irritable bowel syndrome,
00:21:45.860
ulcerative colitis. How does the microbiome affect those things?
00:21:50.880
Yeah, the gut diseases are pretty obvious to think about. Let's take inflammatory bowel diseases,
00:21:55.500
that's ulcerative colitis. And basically what happens is people with these diseases,
00:22:00.640
they have a genetic defect that basically they're not able to fight off or block the bacteria from
00:22:06.520
penetrating through the gut. So some of these inflammatory microbes get through and they then
00:22:11.000
trigger the inflammation, which then causes inflammatory bowel disease, which is basically
00:22:15.080
inflammation in the gut. So that's fairly straightforward that basically the gut bugs are
00:22:19.580
triggering inflammation, causing intestinal inflammation, causing these diseases. What's less
00:22:23.820
straightforward is say, for example, you know, Alzheimer's and dementia and Parkinson's,
00:22:27.680
for example, but gut microbes play a role in that. We know they play a major role in obesity.
00:22:33.280
This was established many years ago when people could take feces from a fat mouse and put in the
00:22:38.520
thin mouse and it got fat. And they could take a fat mouse, put the feces in the thin mouse,
00:22:43.160
it lost weight. And they could take feces from heavier set people, put it in mice, they would then
00:22:47.420
gain wheat. Unfortunately, we haven't narrowed it down and say, well, here's the perfect, you know,
00:22:51.960
lean bug, for example, have this bug and you'll be fine. And of course it's linked to diet. But,
00:22:56.220
you know, we now know that obesity, which is also a precursor to type 2 diabetes is heavily linked
00:23:01.260
with the gut microbiome composition. Yeah. With obesity, it seems like it's both
00:23:05.720
causation and correlation. So yeah, your microbes influence your weight, but your health habits
00:23:11.320
influence your microbes. And I thought the transplanting microbes from an obese mouse
00:23:16.640
into a non-obese mouse can actually cause weight gain was really interesting. There's also a case study
00:23:22.260
in humans where a woman who received a fecal transplant from her overweight daughter to
00:23:28.880
treat some bacteria infection she had, that woman later gained significant weight and became obese
00:23:35.000
herself despite she, and she never struggled with her weight before the transplant. So, so when there
00:23:40.680
is causation, is there a theory as to the mechanism? Like why does it certain micros make you more prone to
00:23:49.160
be obese or overweight? Yeah. The current theory is there's a, basically the obese microbes are
00:23:53.740
really, really good at harnessing energy out of any kind of food. So they generate a lot of energy
00:23:58.420
for not much input. And ironically, the healthy ones, Juno fiber stuff, they're actually kind of,
00:24:04.000
I was going to say crappy, but that's probably the wrong pun to use. They're not very good at
00:24:07.360
digesting the food. They don't generate as many calories. So these obese microbes just generate
00:24:12.220
calories like there's no tomorrow because they think you're starving or whatever. So they have to
00:24:15.880
generate a lot of calories. So that's the current thoughts, but it's not proven. And I think there's
00:24:21.060
still a lot of discussion in that area. Let's talk about another disease of the gut, colon cancer.
00:24:27.160
Yeah. This is an interesting one because like one of my guilty pleasures is I checked the Daily Mail,
00:24:31.780
the tabloid from the United Kingdom. And like one of their reoccurring things that always freaks me out
00:24:37.220
is young people getting colon cancer. And I'm like, oh my gosh, what's going on? Because you hear about
00:24:42.340
these stories of not only like 50, 60-year-olds getting colon cancer, but like 30-year-olds,
00:24:46.840
20-year-olds. And they have all these theories like it's your microbiome and your diet is causing it.
00:24:51.580
So what do we know about the role that the microbiome plays in colon cancer?
00:24:56.860
Yeah. I'm guessing that's what the princess had, for example. I mean, you're right. And this is
00:25:03.120
really scary because we are seeing a real increase in 35-year-olds and things. Historically,
00:25:08.080
it's been an older one. Just last week, I had the lovely pleasure because I'm getting older of going
00:25:12.640
through a colonoscopy. And I felt so sorry for my microbes because they must all be gone because you
00:25:18.000
have to clear them all out to get scope, for example. But so what we think is going on is because
00:25:23.540
for, again, our Western diet and our unhealthy microbes that they're, you know, sort of constantly
00:25:28.120
triggering inflammation in the gut, that's causing tissue damage. And then when tissue is repaired,
00:25:32.760
sometimes it's repaired incorrectly. You can get a mutation which can lead to cancer,
00:25:36.100
for example. And so we think that the diet, the unhealthy diet is associated with all these,
00:25:42.360
you know, disruptions in the gut that is then leading to colon cancer. There's also a micro
00:25:46.840
type of E. coli being associated with it, but it's not really fully proven yet, but it seems to be
00:25:51.200
associated with it too. But I mean, one moral of this discussion is that if you're young, don't rule
00:25:56.720
out getting screened for colon cancer. If you have a family history of polyps or colon cancer,
00:26:00.740
get the screen. I know it's gross, getting cleaned up for a day, but it could easily save your life.
00:26:07.120
And just because you're, I don't know, 35 no longer means you're immune to it, you could easily have
00:26:11.380
it. So get screened. The good thing is that colon cancer takes a long time to present. It's, you know,
00:26:17.180
about a decade or so. So for example, mine, I was clean. So they said, come back in five years.
00:26:21.460
So if you get the polyps, which are precursors to colon cancer, you can actually then prevent the
00:26:26.260
disease. And colon cancer is a horrible disease. So I know I'm preaching now, but this is something
00:26:31.460
that I think that we didn't really realize before. And it's really becoming prevalent among younger
00:26:35.500
people. And this can be a life-saving thing. We're going to take a quick break for your words
00:26:39.860
from our sponsors. And now back to the show. Okay. So we talked about the gut health, the role that
00:26:47.320
the microbiome plays in that. Let's talk about the role the microbiome plays in our immune system.
00:26:53.300
What's going on there? Everything. Okay. Yeah. Yeah. This has been, I think, a real cornerstone
00:27:00.540
of the whole microbiome field is what we realized is that even early in life, the microbes in the gut
00:27:06.760
are influencing how your immune system develops. And we had some studies that we did in our lab where
00:27:11.620
we showed that we could actually predict whether kids would get asthma or not based on their microbiome
00:27:16.660
at three months of age, because it would either push you towards an asthmatic allergic type reaction
00:27:21.500
or a non-asthmatic thing based on the microbiome. And what we now realize is the microbiome is heavily
00:27:27.120
programming the immune system to go the right way or the wrong way. And that's why kids that are born,
00:27:33.480
say, by C-section, they get the wrong microbes or antibiotics, the wrong microbes. They tend towards
00:27:38.480
asthma and allergies because they don't have the right microbes that are cuing their immune system up
00:27:42.320
correctly. And then all through life, the microbes are tweaking the immune system,
00:27:46.140
and it plays a really important role in this thing. And we talked a lot about fiber as being
00:27:52.340
anti-inflammatory. And I'll dive into this now. I mean, one of the key things about aging is this
00:27:58.700
chronic inflammation. Now, we know inflammation is good for fighting off infections and things,
00:28:03.500
but we now realize is as you get older, two things happen. You get more inflammatory microbes,
00:28:08.220
the bad ones, and your gut gets more permeable. And then these permeable bad microbes seep into the
00:28:13.740
body. They trigger this low-grade inflammation. And it's what we call inflammation. And as I was
00:28:18.700
writing the book, it was just scary because every aging process I looked at basically boiled down to
00:28:23.500
the same concept. Get older, microbes get bad, trigger inflammation, causes tissue damage,
00:28:27.740
which then causes, and you pretty much fill in every single one of the aging processes we see.
00:28:33.460
And studies have been done in mice, not humans yet, that you could take feces from an old mouse,
00:28:38.280
put it in a young mouse. It triggers inflammation, that mouse ages faster. And even better, if you
00:28:43.520
take feces from a young mouse, put it in an old mouse, it slows down the aging process, less
00:28:47.560
inflammation, and actually allows these mice to live longer. So maybe feces from a young person
00:28:52.980
really is the thought in youth. We don't know that yet, but it plays a major role in the whole aging
00:28:59.100
So you mentioned gut permeability. I've heard that phrase thrown around a lot, and I kind of understand
00:29:04.260
what it is. Like, what is that gut permeability?
00:29:06.960
Yeah, we already talked about the gut being a tube, right? Well, it's not a polyethylene tube
00:29:11.760
that nothing can get through. It has to be permeable because you have to get the nutrients
00:29:15.120
from inside the gut into the body. So there's a bunch of cells that make up the wall of this tube,
00:29:20.360
and they're basically glued close together, and they have specific ways of transporting stuff
00:29:24.960
across that barrier. But in some cases, if you break the junctions between these cells,
00:29:29.600
you basically cause a leak in the pipe. And really, gut permeability is basically a leaky
00:29:34.360
porous type tube pipe, whatever you want to call it, in the gut. And so things beyond molecules can
00:29:40.980
seep through, and with these holes in the gut, now microbes can actually seep through true,
00:29:45.180
and then the body's immune system goes nuts when it sees these microbes because they shouldn't be
00:29:48.620
in the body, and that's when you trigger the inflammation. So leaky gut, permeable gut is just
00:29:53.440
as it says. It's basically your intestine is not as tight and as glued up as it should be.
00:29:57.780
Okay. So an unhealthy gut microbiome can cause inflammation because we have these microbiomes
00:30:03.020
that cause inflammation. Are there microbiomes that actually strengthen our immune system,
00:30:11.000
Yeah. There's a lot of studies starting to come out. There's some really neat studies on vaccine
00:30:14.600
responses that good microbiome gives you a better vaccine response than bad, for example. And we know
00:30:19.340
vaccine responses are going through the immune system. There's really nice studies showing out the
00:30:23.680
diet really does improve the immune system, and it's going through the microbiome.
00:30:27.780
So following a Mediterranean diet, for example, there's nice studies showing that actually does
00:30:32.060
strengthen the immune system and makes it stronger and allows you to fight off infections and all the
00:30:35.800
other things that the immune system does. So yeah, as to which bug's doing what, I think the details are
00:30:41.940
still being filled in. We don't have all the answers yet, but there's no doubt this plays a big role
00:30:47.040
Related to the immune system are autoimmune diseases, where your immune system goes on overdrive and
00:30:52.720
starts attacking healthy parts of your body, like a common one, rheumatoid arthritis or multiple
00:31:00.540
Yeah, MS. Is there a connection between the microbiome and autoimmune diseases?
00:31:04.440
There is. People with those diseases have different microbes, morpul inflammatory, as we discussed.
00:31:09.220
So there is a correlation, but I can't tell you mechanistically how do they cause MS or rheumatoid
00:31:16.960
arthritis. I mean, we know certain microbes associated with it. There's very good predictions
00:31:20.580
involved. Presumably, these microbes are triggering inflammation and stuff that causes the body to
00:31:25.840
react with itself and cause these autoimmune diseases. So there's correlation, but not causation yet.
00:31:30.860
Not causation yet. Okay, let's talk about brain health. So you mentioned some diseases that are
00:31:34.640
connected to the microbiome. Alzheimer's is one you mentioned earlier, but even depression. There's
00:31:40.220
like a connection or correlation between the microbiome and depression. Talk to us about that.
00:31:45.960
Yeah. I mean, I think, you know, one of the most exciting areas in this field is what we call the
00:31:49.240
gut-brain axis. How do the microbes influence the brain? Now we know the brain influences the gut.
00:31:54.240
There's this nerve that goes down called the vagus nerve that influences gut motility and things.
00:31:58.720
But now we realize that microbes are pulling out the other end of this nerve and they're sending
00:32:02.240
signals up to the brain. And just to give you some examples of how this all works is if you take an
00:32:08.020
anxious, stressed, or depressed mouse or rat, do a fecal transfer into a normal mouse or rat,
00:32:14.160
those normal mouse or rat now become anxious, stressed, or depressed just by transferring the
00:32:18.640
microbes. There are studies in the UK that have done big studies. Look, people use antibiotics.
00:32:23.840
They are much more susceptible to anxiety, depression type thing. So there's these microbial links there.
00:32:29.880
And then the big ones in terms of mental aging diseases, of course, are Alzheimer's and to a
00:32:35.000
lesser extent Parkinson's disease. These are two awful diseases. Alzheimer's is basically the type
00:32:40.560
of dementia. But microbes seem to be involved in that probably because triggering the inflammation,
00:32:46.440
triggering the tissue damage, triggering the brain damage. And as we talk about in the book,
00:32:51.100
that if you eat a healthy diet, something called the MIND diet, which is basically a modified
00:32:55.160
Mediterranean diet, you can drop your incidence of Alzheimer's disease by over 50%, which is just
00:33:01.560
stunning in that sense. And work we've done in our own lab is that working on Parkinson's disease,
00:33:07.800
that's a disease that causes tremors and you're sort of stooped over and stuff. It's about 1% of
00:33:12.740
the population. And we showed that basically if people followed the MIND diet, again, which is the
00:33:19.260
Mediterranean diet, basically, that it delayed the onset of Parkinson's in women by 17 years and by
00:33:25.120
men by over a decade. And given the Parkinson's doesn't actually kick in until age 65 plus normally,
00:33:31.720
you're going to die of something else first. And we know this has got microbe related because we've
00:33:36.700
done all the studies showing that gut microbes and Parkinson's are different. And it all got started
00:33:41.260
by cutting the nerve that hooks the gut to the brain, the vagus nerve. When you cut that,
00:33:45.020
you have less levels of Parkinson's. And so the way we think Parkinson's actually works now is it
00:33:50.860
starts in the gut. And the biggest indication of getting Parkinson's is constipation 30 years before
00:33:56.060
you get it. And the second biggest risk factor is eating red meat. So these are both gut things,
00:34:01.020
right? And so we think basically you have a bad gut microbiome and it causes misfolding this protein in
00:34:07.780
the gut, something called alpha-synuclein. And that goes up the vagus nerve into the brain,
00:34:12.420
part of the brain that makes this dopamine, which suppresses tremors and things. And it
00:34:17.160
destroys those cells. And then you start to see that the brain disease and depression.
00:34:21.940
So bottom line is prevent these diseases, eat a healthy diet. And I think that really bodes well
00:34:27.120
for good brain health. There's all sorts of research. Can we find a magic bug that decreases
00:34:32.180
depression and stuff? Psychobiotic, you call these things. We don't have these yet. There's some hints of
00:34:37.880
probiotics and things, but we don't have good data yet. But that's where this is all going. Can
00:34:42.300
we actually influence the brain via gut microbes? Yeah. One thing I've seen, and this is all
00:34:46.880
speculative, of course, but with depression, one thing I've seen thrown out there for, oh,
00:34:51.500
here's how you can help it, is eat resistant starch, like a food with resistant starch. And then
00:34:57.840
I guess the gut microbiome breaks that down into the short chain fatty acid, particularly like
00:35:03.560
butyrate, I think that's how you putyrate. Yeah. Like the more butyrate you have, somehow that's
00:35:07.740
supposed to help stave off depression. I don't know. Yeah. Good job, Brett. You turned into a
00:35:11.320
scientist. Yeah, I'm a scientist now. Yeah, I'm an expert. Yeah. So fiber basically is broken down
00:35:17.220
into what we call short chain fatty acids, and butyrate is the big one among these things. The
00:35:22.580
joke is if you're at a microbiome concert, you want to know, meeting, you want to know what the
00:35:26.580
Wi-Fi password was, it's probably butyrate, because butyrate seems to be involved in absolute
00:35:29.780
everything. And butyrate is an anti-inflammatory molecule that decreases inflammation. And so the idea
00:35:35.820
is that if you're depressed, you know, eating a better diet, you decrease the inflammation,
00:35:39.920
hopefully decreased, you know, symptoms associated with it. Ironically, it all gets boring. It all
00:35:45.020
boils down mainly to diet and exercise. It's just boring. I want the magic pill, right?
00:35:49.820
Unfortunately, the magic pill is eat right, get some exercise, don't stress, get a good night's sleep,
00:35:55.060
and enjoy life, really. But that doesn't come in a pill form, so.
00:35:59.040
Yeah. At the end of this conversation, we'll talk about what you can do for your microbiome health,
00:36:01.580
and it'll be like, it's basically a recap of what you've been saying throughout. Eat a good diet,
00:36:05.880
but we'll get into more specifics. You have some other interesting things there.
00:36:08.200
Yeah. Let's talk about the microbiome in our mouth. So that's the opening of that tube
00:36:12.480
that goes through our body. How does our microbiome in our mouth affect things like
00:36:20.280
Well, it drives both those things. I mean, ironically, the microbiome in the mouth is the
00:36:24.200
earliest studied microbiome. There was a guy named Anthony van Leeuwenhoek in the late 1600s who
00:36:29.200
invented the microscope, and he wanted to look at things. He looked at cool things like his sperm,
00:36:33.740
but the other things he did is he swabbed out his mouth, and he made this most profound statement.
00:36:38.480
There's more animalcules, which we now know are bacteria, in his mouth than there are people
00:36:43.580
living in the Netherlands, which is where he's living at the time. Of course, no one believed
00:36:47.360
this crazy guy seeing what you can have living things in, but ironically, that was, of course,
00:36:51.260
the mouth microbiome. And your mouth is full of microbes. It's a fun experiment. Swab it out,
00:36:56.500
stain it. You'll see all these microbes in there. And they do all sorts of things. Yes,
00:37:00.740
some cause teeth cavities, so they chew away at the enamel in the teeth and then bury into it,
00:37:05.400
and that causes teeth cavities. One of the bigger problems is they cause inflammation of the gums
00:37:10.400
around the teeth. Whenever you go to the dentist, they floss your teeth. Why are they telling you to
00:37:14.140
floss your teeth, brush your teeth? Well, that's because it's for good gum health. And if you have
00:37:18.280
crappy gum health, then it's inflamed. There's microbes living there. And also, that allows the
00:37:24.160
inflammatory microbes to seep into your body, and they get through these inflamed guts and then cause
00:37:28.240
the problems associated with the inflammation. And just to give you interesting examples that,
00:37:34.300
you know, if you brush your teeth three times a day, you basically drop your Alzheimer's rates
00:37:38.080
by about 50%. You say, well, what does good oral health have to do with Alzheimer's? And of course,
00:37:43.860
the answer lies in the microbes that if you don't brush your teeth, you have poor gum health.
00:37:47.980
Microbes seep through. They trigger inflammation, causes tissue damage, which then seems to be
00:37:52.000
associated with Alzheimer's disease. Yeah. Whenever I go to the dentist, there's next to the chair,
00:37:56.380
they have this poster, and it's got a body on there. And it points to all these things. If you
00:38:01.620
don't floss, here's how it's going to affect, like one of them is heart disease. Like if you don't
00:38:06.660
floss and you get, you're going to have periodontal disease and you're going to have a heart attack.
00:38:11.740
And I'm like, okay, I need to floss. I need to start flossing again. And then my motivation lasts
00:38:16.880
for like three weeks. So yeah, what role does the mouth microbiome play in heart disease? Is it the
00:38:23.900
same for things, just inflammation? Same as we were discussing, these inflammatory type
00:38:29.060
things that inflation is hard on the heart. And then it could lead to these heart things because
00:38:33.300
you allow the microbes to seep into the body. Because just like the gastrointestinal tract,
00:38:37.700
the mouth is generally pretty impermeable for allowing bugs into the body, unless you have poor
00:38:41.840
gum health. And then that's a ticket for all these oral microbes to then seep into the body and trigger
00:38:47.200
these problems. So yeah, it's an interesting way of guilting you into flossing your teeth and stuff,
00:38:51.620
but it's actually good for you. And that's why it's a good gum health.
00:38:55.680
One thing you mentioned in the book as kind of an aside, but inspired me to go try this out.
00:39:01.000
Probiotic gum for oral health. Is there anything to that?
00:39:04.540
There's some. I mean, every time you go and get your teeth cleaned, especially if you do what's
00:39:08.840
called an acid wash, they just destroy all the microbes in and on your teeth. The reason you're
00:39:13.000
getting teeth cleaned, all that plaque, all that white stuff they chip off, they're called
00:39:17.000
extracellular polysaccharides. They're carbohydrates, they're sugars basically that these microbes
00:39:20.920
produce and they build this basically impermeable wall around them. And that's when they're chipping
00:39:26.820
off the plaque. But every time you get your teeth cleaned, they strip it down to nothing.
00:39:30.940
And it's really interesting as to which bug adheres first. That sets up the hierarchy of
00:39:35.300
who's going to then come next. And depending who adheres first, that dictates who's come second
00:39:39.820
and third and stuff. So this probiotic gum seems to actually help establish getting good microbes
00:39:45.320
down first. So they set up the rules. Okay, we're going to be a good call in here. We're going
00:39:49.120
to build these microbial skyscrapers based on this as opposed to based on, say, a pathogen.
00:39:54.600
So there's some data on the probiotic gum, much like all probiotics. It's not that great
00:39:58.800
data yet, but there's some there. And so, yeah, how did it taste?
00:40:02.860
It was okay. I mean, it tasted like gum. It was kind of, it was a little chalky.
00:40:10.360
We'll talk more about probiotics here because I think that's interesting. But let's talk about
00:40:13.480
one more thing, the microbiome on our skin. I've been seeing more about this in advertisements
00:40:19.600
with skincare products. They talk about, oh, this is good for your microbiome on your skin.
00:40:28.220
Yeah, well, as I said, you have microbes coated all your skin and wet areas, there's more microbes.
00:40:33.300
But each place on your skin has a certain microbial collection and your right hand is going to be very
00:40:37.420
different than your left hand because they do different things and they touch different things and
00:40:41.300
that's normal. But one of the biggest things they do is they fight off, they basically hog all the
00:40:46.980
sites that a pathogen could buy to. So skin effects and stuff are less than people with
00:40:51.500
healthy microbiomes. They also seem to be helping with skin health. And you know that as a teenager,
00:40:57.460
when you get pimples, for example, that's because the bacterium is chewing on the oil your face makes
00:41:01.600
as a teenager and that then generates some acne and pimples, for example. There's interesting stuff
00:41:07.240
coming out on probiotics and skin health. It's not perfect, but I think there's some
00:41:11.180
interesting data coming out that seems to enhance it. And not just skin microbes, gut microbes.
00:41:15.780
There's lots of studies coming out showing that if you have healthy gut microbes, it actually
00:41:18.940
improves your skin health and helps decrease radiation damage when you get sunburned, for
00:41:23.720
example. Both the skin and the gut microbes seem to decrease the skin damage that ultimately
00:41:29.060
results in wrinkles and your skin collapsing as you get older and all the skin things associated
00:41:34.240
with aging. So yeah, the cosmetic industry is certainly capitalizing on this. They kind of take
00:41:39.500
it too far, in my opinion, sometimes. But there is some interesting stuff coming out that you can
00:41:43.220
actually put microbes in skin creams and then may enhance your skin health type thing.
00:41:49.120
Yeah. I mean, one thing that you speculated on is that maybe you could bank your microbiome,
00:41:54.440
skin microbiome, when you're like 20, so that when you're in your 60s, you can like apply it on your
00:42:03.540
Sheer speculation, but we know that the microbes on your skin at 60 are different than those at 20.
00:42:08.820
And are they doing this? I don't know. And they've done experiments in mice and other things. And
00:42:14.080
even in people where they take older people, microbes put them on younger people, seems to
00:42:18.440
cause poor skin health and vice versa kind of thing. So yeah, I mean, maybe there's hope.
00:42:25.340
We all want to look good forever, but maybe this could help.
00:42:29.320
I thought it was interesting too. Just kind of my mind was blown when I heard about this.
00:42:32.600
Just speaking of our microbiome on our skin, because it's the one that's
00:42:36.180
most exposed to our environment. But you talk about how every one of us has our own unique
00:42:42.500
microbiome. We all have a different one. And you could go into like a hotel room and your microbiome
00:42:48.920
will just like populate that entire hotel room. You can tell like, okay, this family was in this
00:42:54.920
hotel room just by measuring the microbiome, like on the TV remote control.
00:43:00.660
Yeah. Then another family comes in and like that microbiome just colonizes and takes over.
00:43:05.160
Yeah. I mean, changing the sheets isn't enough. It's just the way it is. We slough skin cells.
00:43:09.460
We also slough microbes and you can easily see the microbial signatures of people. And as you say,
00:43:14.800
they change over as the people change over. There's nothing wrong with it. It's just biology in
00:43:19.140
action. It's what it is. And like, it's not associated with getting infected with someone because
00:43:23.440
the people before you had some microbe, it's just the way it is. It's just biology.
00:43:27.460
Okay. Let's talk about nurturing a healthy microbiome because I'm sure this is the thing
00:43:31.560
that people want to, this is what they're listening for. Like, what can I do to have a
00:43:34.260
healthy microbiome? And we've mentioned some things already, but the diet sounds like just
00:43:38.100
eat a well-balanced diet, particularly a lot of fiber because your gut microbiome needs that.
00:43:44.100
Yeah. So diet is first and foremost, the biggest thing that affects at least especially your gut
00:43:48.420
microbiome. And the more plant fiber you eat, the better off you're going to be. You want to
00:43:53.000
decrease red meat. You can probably have it once in a while, but you should not be eating red meat
00:43:57.220
regularly. That's not good for the microbiome. And of course, stay away from processed foods,
00:44:02.520
including things like white sugar and white flour. Always go for the whole grains.
00:44:06.960
And sort of the saying is, you know, walk around the outside of the grocery store and stay away from
00:44:11.300
the middle because in the middle is all the processed foods. There's nothing good for microbes in
00:44:15.080
there whatsoever. And you want to stick to the, you know, the produce counters and stuff like that.
00:44:19.800
So diet is first and foremost, the biggest one.
00:44:23.020
What about fermented foods? Because that's food that has bacteria in it. Does that have a benefit?
00:44:28.140
It does. Kimchi. During COVID, I worked on becoming a sourdough bread maker kind of thing
00:44:35.200
because everyone did. And, you know, I thought, well, sourdough bread, it's cooked, right? So is it
00:44:40.540
probiotic or not? And it turns out that it's actually good for you because of all the microbial
00:44:44.980
products that are in the cooked bread and they've broken down the things in a beneficial way.
00:44:48.860
But yeah, all fermented foods are, generally speaking, they're quite good for you and definitely
00:44:54.860
Yeah. I eat, part of my routine is I have, with breakfast, I have like a scoop of kimchi.
00:45:00.000
Excellent. Or sauerkraut or anything like that.
00:45:02.120
Sauerkraut. I love sauerkraut. And then I eat yogurt. I like, you know, Greek yogurt is another
00:45:06.900
thing I eat. What about mentioning probiotics? Because we typically think, okay, eat yogurt because
00:45:13.020
it has probiotics. Eat kimchi has probiotics. Probiotic supplements, you're seeing advertisements
00:45:17.960
for this all the time. Do probiotics actually do anything for us, like the supplement types?
00:45:24.320
Yeah, this is a hard one. Bottom line is a probiotic, basically, it's not going to hurt you.
00:45:30.960
But the real argument is it's good for you. And there are some probiotics that we've proven
00:45:35.100
in clinical trials for some clinical indications. There are some probiotics that can be used for,
00:45:40.800
say, antibiotic-associated diarrhea. Take antibiotic diarrhea. Some work there.
00:45:45.960
There is yeast, means it's associated with decreasing clostridium difficile infections.
00:45:50.300
The analogy I like to use is that you need a new pair of runners. You walk into a running
00:45:53.940
shoe store and there's this wall full of runners. There's joggers and hikers and basketball shoes
00:45:58.420
and tennis shoes and whatever. You don't just grab the cheapest pair and walk out.
00:46:01.780
And say with probiotics, you just Google the word probiotic chart and there's one for both
00:46:06.880
U.S. and one for Canada. And there it lifts what all the probiotics are and what is the clinical
00:46:12.340
evidence they will do something for a particular disease. Now, there's no probiotics that have been
00:46:17.880
proven to basically make you feel better because that's clinically a really tough endpoint and
00:46:23.080
no company's ever going to want to do that. So there's some that work, but really they're quite
00:46:28.400
few and the clinical evidence is very poor. They're not like night and day like an antibiotic
00:46:32.760
treatment. It's just night and day for curing an infection. But all that said is I'm really
00:46:37.940
hopeful for the future we'll get into these worlds where we're adding eight, ten microbes and it'll
00:46:43.280
have a defined biochemical outcome. They'll be taking that as a drug really. It's gone through
00:46:47.340
the clinical trials and there's several that are now coming down the pipes of exactly this where
00:46:51.840
you get a prescription from a doctor for this mix of microbes to actually do this. And I call that
00:46:57.520
probiotics 2.0 or next-gen probiotics. I think that's where the real excitement's coming.
00:47:01.540
Okay. So it sounds like take one if you want. It's probably not going to do much for you.
00:47:06.960
It's not going to hurt you. But it sounds like you're probably going to get more bang for your
00:47:10.180
buck focusing on the prebiotics, like eating the fiber food that gives your microbiome stuff to
00:47:17.820
Yeah. I mean, there's three classifications. There's probiotics, which are basically live microbes.
00:47:23.420
And they tell you how many microbes are alive when you take this thing. The problem is that they
00:47:28.400
pretty much die as soon as they go inside you. I mean, for example, lactobacillus is a microbe from
00:47:33.120
the vagina, which is a very different world than the gut. And you swallow this lactobacillus,
00:47:37.960
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.
00:47:43.320
So that's why you have to take them every day. It's a great marketing point of view because you
00:47:46.880
have to take this every day. But you're just basically taking a microbial goo kind of thing.
00:47:50.700
So, you know, the new mixtures will be microbes from the gut and for the gut that will actually
00:47:55.740
then take that and actually set up a colony and live in the gut. And it's not such a great marketing
00:48:02.560
design because ideally if it works, you should only have to take it and then you want to take
00:48:06.740
it again. But that's where we're heading with these things.
00:48:10.140
Gotcha. What about any activities? Like you talked about let them eat dirt. You want your kids out
00:48:15.440
there playing in the mud. As an adult, should we be doing the same thing? Getting out in nature
00:48:19.520
and possibly making mud pies? Absolutely. Yeah. Especially if you can insult your microbes,
00:48:24.420
like you'd have to take antibiotics for an infection. How do you fix them? There's no
00:48:28.000
mix of microbes you can actually just take right now to make your microbes good. The best way is
00:48:32.580
eat healthy and get outside and, you know, embrace microbes. Let your dog look you in the face,
00:48:39.240
for example, all these kinds of things that generate microbes. I mean, you know, you take elder care
00:48:44.660
homes, you think how we treat people in there. I mean, I personally think there should be dogs and little
00:48:48.900
kids running through these places and let them defecate all over the place. And that's how you're
00:48:52.800
going to get these young microbes into the elderly, as opposed to the crustless white sandwiches and
00:48:57.600
don't let anyone in kind of thing. I mean, that's a terrible way for a microbe point of view to live.
00:49:01.840
So embrace your microbes and then doing that, that'll actually improve your health.
00:49:05.580
And then also don't be so sanitary inside your house.
00:49:11.720
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
00:49:16.600
falls on the floor, it's just fine. It's not, you know, unless it lands on a pile of bolts or
00:49:20.400
something, it's fine. So yeah, it's this balance of hygiene and stuff. I mean, other, other proactive
00:49:25.080
things. So we talked about diet. I mean, exercise is really important. Exercise really decreases the
00:49:30.540
inflammatory microbes and pushes your microbes to a more anti-inflammatory type thing. And all the
00:49:35.620
studies show that we know exercise is good for us. It's actually really good for your microbes too,
00:49:39.900
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
00:49:45.000
marathon runner, but just, you know, even daily walking of things has a massive effect on the
00:49:49.380
microbes. You want to get a good night's sleep, diet has a big effect on microbes that allow you
00:49:54.440
to sleep better and type things. So there's good sleep. The point we have the most problem with in
00:49:59.160
our society, I think, is stress. And we live in a very stressful world. I mean, even if I sit there
00:50:04.480
all day, my watch says, you have had a stressful day, you should relax. Now it drives me nuts. But,
00:50:08.300
you know, stress has a terrible effect on your microbes. Again, driving them towards the
00:50:13.500
pro-inflammatory type thing and basically making them bad microbes again. And the final thing is
00:50:19.480
community. And this is one thing we tend not to embrace so much is that, you know, community is
00:50:24.880
really important. And that's probably because it's microbial swapping. There's a cool study that could
00:50:29.020
tell who played cards with who based on their microbial composition. So you're swapping microbes with
00:50:34.260
your friends kind of thing. So I jokingly say maybe dating apps should have a microbiome screen so
00:50:39.780
that you can, you know, who are you dating and what are your microbes? I don't know yet.
00:50:44.760
Okay. So to have a healthy microbiome, you want to avoid processed foods, eat more fiber,
00:50:50.040
maybe some fermented foods, exercise that decreases inflammatory microbes, de-stress. Don't be overly
00:50:57.700
scrupulous about hygiene. You recommend not using antibacterial soap unless absolutely necessary.
00:51:04.260
Because just plain old soap and water works is fine in most cases. Sleep is also another component
00:51:09.720
to a healthy microbiome. There's a two-way relationship there. Good sleep supports a
00:51:14.420
healthy, diverse microbiome while disrupted sleep can start just kind of throw things out of whack
00:51:19.880
in your gut. And then in turn, the gut microbiome can help regulate sleep-related hormones like
00:51:26.360
melatonin, GABA, serotonin. So, you know, that means a healthier microbiome can lead to better sleep
00:51:32.540
or support better sleep. And then hang out with people. Diversify your microbiome by getting in
00:51:37.260
contact with other people's microbiomes. And then another thing I think is just be judicious with
00:51:43.760
antibiotic use. So if your doctor prescribes you antibiotics, you can ask, do I really need to take
00:51:49.360
antibiotics? Yeah. I mean, historically, we sort of say, well, antibiotics can't hurt. Take them anyway.
00:51:54.160
I mean, kids with otitis, medias with ear infections, they get prescribed antibiotics all the time.
00:51:58.420
Well, that's often a viral infection and the antibiotic's not going to do anything.
00:52:02.780
And there's two reasons why you want to avoid antibiotics. One is the increase in the antimicrobial
00:52:07.280
resistance, which is a huge issue. Bugs get resistant to it. But secondly, now it has a really
00:52:12.960
carpet bombs your microbiome. So if you have a life-threatening disease that antibiotics are
00:52:17.980
needed, absolutely take it. But if it's something that, ah, might not work or whatever, I think there's
00:52:23.120
still the lack of realization out there that they do have these secondary effects. And people take
00:52:28.520
antibiotics are much more prone to be obese, have high levels of asthma, have mental diseases. There's
00:52:33.580
all these studies coming out now showing that long-term multiple antibiotic use is really just
00:52:37.920
not good for you because it impacts your microbiome. Well, Brett, this has been a great
00:52:41.900
conversation. I think we understand the microbiome now. Where can people go to learn more about the
00:52:45.600
book and your work? Well, it's called The Microbiome Master Key. Harness your microbes to unlock
00:52:50.620
whole body health, lifetime vitality. It's available on Amazon, etc. You can Google me. We have a lab
00:52:57.200
webpage and thinking about our work. And also, like I said, if you have kids, look up Let Them Be Dirt or
00:53:02.740
watch the YouTube video of the documentary on that thing. I guess I just urge people to think about how
00:53:08.100
we live and to embrace the microbes as part of our living. And when you scroll through the news and
00:53:13.440
stuff, it's all about exercise and things. But why is that good for us? And we now realize that a
00:53:18.460
major component of that is the microbes. And the good thing is you can change your microbes. You
00:53:22.360
can't change your genes, but you can change your microbes. So if we can change our microbes,
00:53:26.140
there's actually hope for fixing things and basically pushing more towards the health and
00:53:29.900
vital type aging process. So that's the idea of all this.
00:53:33.940
Fantastic. Well, Brett Finlay, thanks for your time. It's been a pleasure.
00:53:37.040
My guest here is Dr. Brett Finlay. He's the co-author of the book, The Microbiome Master Key. It's
00:53:42.220
available on Amazon.com and bookstores everywhere. Check out our show notes at
00:53:45.080
awim.is slash microbiome, where you can find links to resources when we delve deeper into this topic.
00:53:57.160
Well, that wraps up another edition of the AWIM podcast. Make sure to check out our website at
00:54:00.980
artofmanly.com, where you can find our podcast archives. And make sure to check out our new
00:54:04.420
newsletter. It's called Dying Breed. You can sign up at dyingbreed.net. It's a great way to support the
00:54:08.820
show directly. As always, thank you for the continued support. Until next time, it's Brett McKay.
00:54:12.780
Remind us how to listen to the AWIM podcast, but put what you've heard into action.