Ep. 54 – Dr. Brett Finlay – Let Them Eat Dirt: Saving Your Child From an Oversanitized World

Rachel Cram – Well, Dr Brett Finlay, actually, I think I should call you, Sir Dr. Brett Findlay because you have the Order of Canada.

Dr. Brett Finlay – I do. It’s quite an honor. Yes. And in Britain it would be Sir, but here, you can just call me Brett.

Rachel Cram – OK. Well, in preparation for this interview, I’ve had you in my head for the last month.

Dr. Brett Finlay – Well that’s worrisome. Poor you.

Rachel Cram – No, it’s been so fascinating. I’ve been reading your books and articles as well as listening to other interviews and I know you were a leader in the vaccine development for the SARS virus. So Brett, you must be watching COVID with complete fascination.

Brett Finlay – Yeah. I mean, from a microbiology point of view, it’s absolutely fascinating. Sometimes I kind of wish I was head of public health because I always seem to be about three weeks ahead of what they decide to do and I’m cussing and cursing, “Oh, guys, do this.”

But yeah. That’s their job.

Rachel Cram – Oh well, a fascinating time. And we definitely want to address COVID at the end of the interview.

But the subtitle of your book is Saving Your Child From An Over-sanitized World, and that is what I would love to dig into with you today.

Dr. Brett Finlay – Perfect

Rachel Cram – I know in the last 10 years, studies on microbiology have just exploded onto the stage, and I kind of like that word exploded because I know a lot of it has to do with diarrhea.

Dr. Brett Finlay – Explosive diarrhea. Yep,

Rachel Cram – Now, I think you’ve referred to our microbes as the unknown organ in our body. Is that right? Is that your term?

Dr. Brett Finlay -Yeah. Well, or the newest discovered organ really, because they weigh about as much as your brain in terms of total mass in your body and they contribute to so many physiological aspects of our normal function that we just previously had no clue about.

Anthonie van Leeuwenhoek found these things in late sixteen hundreds when he built the first microscope but we didn’t really pay any attention to them because you couldn’t grow them and then only recently have been able to get a handle on them with sequencing. And then the field has just exploded.

Rachel Cram – Well, Brett, before we jump into all of this and I know you have so much incredible information to share, I just like to open with a question that gives our listeners a a feel to who you are, and this is my question. Aristotle stated, “Give me a child at seven and I will show you the adult.”

And so, Brett, I’m wondering if we can journey back in your mind, is there a story or experience from your childhood that has shaped the adult that you are today?

Dr. Brett Finlay – Yeah, very much so. And as always, it falls back on parents. Both my parents were naturalists. My dad was an ornithologist, my mother was a botanist and I spent my childhood outside. And, you know, my brother and I would have a competition of how big a ring of mud we could have in the bathtub at night when we had our evening bath. So I was raised in the outdoors, always looking at swamp water through a microscope or measuring the number of sticks in a magpie nest or all these crazy things. So I was raised really as a scientist. Didn’t really think about microbes much, although I did, like I say, look at pond water through a microscope and see all these really cool things in this invisible world we don’t normally think about. But really, that’s where all the roots were laid. And I think Aristotle is right and you’re looking at the guy now many years later. That’s me.

Rachel Cram – Do you think your parents had an awareness of the importance of you being in the dirt? You know your title, Let Them Eat Dirt? Were they aware?

Dr. Brett Finlay – Very much, very, very much. Like I said, they’re both biologists, and I think they realized that we live in an organic world and we should really interface with nature and the environment. Yeah, I think my parents are way ahead of the time. They certainly realized it and really instilled that on us.

Rachel Cram – What a great way to grow up.

Dr. Brett Finlay – Exactly

Rachel Cram – Well, you start off the book by explaining a bit about microbes, and I’m wondering if you can do that for me right now. Can you give a five minute blast of explaining what a microbe is?

Dr. Brett Finlay – Yeah, well, the first important thing is you can’t see them. So you’d look out your hand or your desk or the table where you’re sitting right now and you won’t see these things. So that means they’re microscopic. ‘Micro’ means small and ‘obe’ means life. Now, of course, there’s lots of different kinds of microbes and we generally talk mostly about the bacteria. People know many of these bacteria as ones that cause disease, like salmonella and staph aureus and C. difficile and all these pathogens but there’s also lots and lots of bacteria in and on us, that don’t cause disease and they’re just hanging out there.

Most people have also heard of viruses. COVID is a virus, for example, COVID 19. So there’s viruses.

Then there’s bigger ones. There’s fungi, for example. People have probably heard of fungi and yeast and things like that. And there’s even bigger ones like worms and things that live in the intestine. So there’s this whole blend of microbes living in and on us, but really, in terms of much of the science, we really tend to focus on the bacteria because that’s the one that we can sequence and understand. We know very little about the yeast and the fungi. We’re starting to learn more. And same with viruses. So it’s really this ‘microbial zoo’ living in and on you and this is normal. Don’t freak out. We all have this but you just can’t see it. So you have to believe in the invisible, which is sometimes tough to convince people, but they’re there.

Rachel Cram – What would be the ratio of dangerous microbes that we need to worry about to the non-dangerous type?

Dr. Brett Finlay – Yeah, most microbes don’t cause disease under normal conditions. It’s thought there’s maybe about 100 bacteria that cause human diseases, whereas you have at least as many microbes in and on you as there are human cells. So I’m looking at you now Rachel, I’m supposed to see a human, right? I see more microbes and they actually encode about 100 times more DNA than you as a human encode. And most people kind of don’t really think about it. There is the ick factor but just to put it in numbers perspective, it’s a gross analogy, but if you take a piece of feces about the size of your fingertip there’s more microbes in that feces than there are people on this entire planet. So, you know, there’s trillions and trillions of these microbes on us, and that’s just normal. So I jokingly say, “Think the genocide you commit the next time you go to the bathroom. Mass murder. Bye-bye. Kaflush.”

Rachel Cram – Things you think about. They’re quite different.

Dr. Brett Finaly – Sorry, I have a very perverse sense of humor. I apologize.

Rachel Cram – Oh, you would fit in so great in a preschool classroom of boys? You would be the most popular guy there, and that is so stereotyping so I might have to edit that out.

So I think part of your concern is that there are these, and you can correct me if I’m not saying this right, there are these trillions of microbes and we become anxious about 100 of them and we are doing what you call carpet bombing because of our concern for those. We’re throwing out the baby with the bathwater. Is that kind of what we’re doing?

Dr. Brett Finlay – Yeah, exactly so history really teaches us how this all works. So, you know, late sixteen hundreds Anthonie van Leeuwenhoek finds all these microbes in his mouth and we discovered microbes, but we don’t really do much with that knowledge. And then in late 1800s people like Louis Pasteur and Robert Koch, two very famous microbiologists, they made a seminal step forward. They said microbes cause disease. So they identified what causes tuberculosis. Up until then they had no clue. They thought it was bad air and swamp gas and all these crazy ideas. So they actually showed that microbes cause disease, and Louis Pasteur took it a step further and says, “You kill these microbes, you don’t get disease anymore.”

And that’s where the word pasteurization comes, because that means kill the microbes. So if microbes cause disease and killing them gets rid of them, what do you do? You kill microbes, right? So society went on a one hundred and twenty-five-year campaign. We brought in hand sanitizer, sanitation, sewage systems, antibiotics, vaccines. We went on this massive campaign. And when you look at the infectious diseases in our society today, it is basically gone way, way, way down. Most people don’t have the infections they did 100 years ago.

Rachel Cram – Which is a good thing.

Dr. Brett Finlay – It’s a great thing. And I wish we could say, “Well, we’re done.”

But there’s this really cool curve that shows infectious disease on one side and the other side of the curve is all of our diseases that we see in our society. So that’s asthma and inflammatory bowel disease and cardiovascular disease, all these other diseases that we see, the curve goes the exact opposite direction. It’s going up and keeps going up. I mean, the asthma rates in my lifetime have gone way, way up, for example.

So the question is, well, what’s causing these changes? And I’m going to argue it’s these changes in the microbes. So as we were getting rid of all these pathogens, we collaterally damaged all these others. Because every time you take an antibiotic, yes, you may kill the bacteria that’s caused the infection, but you slaughter billions of other microbes because it’s not just targeting that one, it’s targeting many kinds of bacteria.

So, and then also with this whole cleanliness and I think COVID is really driving this home, how clean we are now, we’re just not getting the microbes. And a good analogy is, think how a kid lived one hundred years ago, a thousand years ago; kids are in intimate contact with their environment. They’re playing in the dirt all the time and they’re constantly getting microbes, they’re sleeping with their animals and in multi communal households.

Now think of a kid that’s born on the 25th story of a condominium, there’s no pets allowed, the playground is on the top of the condo tower with a cement pad around it, and railing, and that’s not how you want to get microbes. And this is our biggest concern is that in our quest, which has been a great quest to decrease infectious diseases, we basically have got rid of all the microbes that we are now realizing were actually important for us and we need to have them. So this is what we call the hygiene hypothesis. We’re just living way too clean, ironically. You’re not going to get smallpox and polio out there, and yet we still are behaving like we might. So this is the main tenet of what we’re trying to say is that we’re living too cleanly now for all the beneficial microbes we’re missing out on.

Rachel Cram – OK, thank you. That was a great introduction to microbiology.

Dr. Brett Finlay – That was more of a rant, but that’s ok.

Rachel Cram – No, it was excellent, thank you.

Musical Interlude #1

Rachel Cram – Now the next part of your book, and I’m visualizing this as kind of progressing through a child’s lifetime into adulthood, if you walk us through that journey? So you start by explaining a bit about microbes, in the next part of your book, you explain what happens to a pregnant woman’s body in terms of her microbiota? Is that the right word I’m using there?

Dr. Brett Finlay – Yeah. Doesn’t matter. Go with whatever you want.

Rachel Cram – Ok, go with that. And then you explain how it affects her children for the rest of their lives. When do microbes even come on to us? Does it start at conception? Does it start at birth?

Dr. Brett Finlay – Yeah, so it’s thought that when a woman is pregnant, the womb is a sterile environment. So generally speaking, the first time that you actually encounter microbes is the day you’re born. And for anyone who’s had a kid, you know, this is a very messy business. This is actually really good. It’s that first big gulp of vaginal fecal microbes that you get on the way out, that’s actually really important for you, and so kids born by C-section miss out on that. We could talk about that in a bit.

But even when the mother is pregnant, what she’s doing is actually going to influence when her kid is born because it will shape her microbes and these kids pick up the mother’s microbes. So, for example, obese mothers, they tend to have a different microbiome. They tend to pass it on to their children and these children tend to become obese because they’ve got the mother’s obese microbes. It’s not because there’s some genetics associated.

So it’s really important that the mother sets up her microbiome in a sense that the child gets the best microbes they can when the kid first hits the world.

Rachel Cram – So they’re not necessarily picking up the microbes from the mother while they’re in utero. It’s as they come out.

Dr. Brett Finlay – No, but the mother’s microbes can make molecules that will affect the fetus in the womb. Even though the microbes aren’t there, the molecules they make can seep through the mother’s circulation and into the child. And there’s some thought that that actually impacts the fetus before it’s even born, because of the mother’s microbes. Yeah.

Rachel Cram – And then you talk about the child coming through the birth canal and all the microbes that picks up there and then also from the feces of the mother, which I found very interesting because when I was delivering my first child, my greatest fear was pooping on the table because I was just so embarrassed about that. And after that, I was like, “Who cares? Just get this baby out of me.”

Dr. Brett Finlay – Exactly.

Rachel Cram – But I was fascinated to hear that that’s an important part of the process.

Dr. Brett Finlay – Yeah, there’s some reason they think the kid comes out facing backwards normally that they access the feces on the way out. The fecal microbes are actually really important because those are the microbes, that and the vaginal microbes, that will help the child then go to break down the breast milk they’re going to get from the mother, and they really set up the whole initial colonization of the child based on that. So yeah, it’s gross but it’s actually important.

Rachel Cram – Yeah, fascinating. OK, so you were mentioning that C-sections don’t give babies that same access and you’re very sensitive in how you write about that in the book, because I know some moms are quite disappointed when they can’t have a vaginal birth. What kind of microbes does a C-section baby get?

Dr. Brett Finlay – So a child born by C-section, they tend to have the microbes that are more like the environment they’re born into, the hospital environment, so they’re very different microbes. Ten percent of all women have to have C-sections. We currently have about twenty-five percent C-section rates, so some are voluntary for whatever reasons. But some places, like in Brazil, they have ninty percent C-section rates. But this really does impact in how it’s setting up for life. If you’re born by C-section, you have about a twenty-five percent higher chance of getting asthma and about a thirty percent higher chance of becoming obese. And there’s a lot of data that indicates that’s because you don’t get the right microbes when you’re born.
But you’re right, many women have to have a C-section for any number of reasons or want a C-section. So the question is, well, what can I do now? And I think the answer is you try and expose your kids to the microbes that they might have gotten. You know, you hug your child, ideally breastfeed if you can, let the dog lick them on the face. And you know, there is even what we call vaginal swabs, where people, if they have a C-section, they will take a vaginal swab of the mother and then they will put it into the child, post birth to try and colonize the child, to see if we can, you know, repopulate or repoopulate, as we jokingly say in our field the microbes to fix them a bit. And so there’s been studies on that, but they’re still ongoing and we have to wait three to five years before we see whether that really works or not.

Rachel Cram – So if a woman discovers that she has to have a C-section or that she’s going to ask for a C-section, is there something she can request of her doctor to address that microbial issue?

Dr. Brett Finlay – Right. Vaginal squads are not a medical procedure, some midwives are doing it. The problem is there’s possible danger if you have something called Group B Strep in the vagina, it could be a fatal disease in the child or cause very serious consequences, so you have to be tested for Group B Strep.

But in terms of just what to do. I mean, I think you just realize, let’s give them every chance we can to get back to normal as quickly as we can by exposing them to different things. I mean, you look around the world we live in, lots and lots of people are perfectly healthy that were born by C-section. It’s not like you’re destined to, “Oh no, this is going to be a horrible life because you’re born by C-section.”

But I think as a parent, you try and encourage microbial exposures as much as possible. There is no medical pill that you can give to say, OK, your C-section, here’s a pill of 40 microbes that you probably have that you wouldn’t have gotten to take this. People are starting to think and work towards this, but that’s certainly not a clinical area yet.

Rachel Cram – You started talking about breastfeeding. Is there anything more you want to say right now about the birth process? Or are you good to…

Dr. Brett Finlay – No, no. Let’s go to breastfeeding.

Rachel Cram – OK, you’re also very sensitive with your information delivery around breastfeeding because some women will have to move to formula or choose to move to formula. With regard to microbes, what do we need to be aware of in that decision making process?

Dr. Brett Finlay – Well, breastfeeding is a natural process just like vanginal birth, and we know that in breast milk, there’s a lot of components that are designed to be then broken down by the microbes that are found in the woman’s vagina and feces. So you populate the kid with these bugs and the breast milk supplies them with food. We now realize that there’s also microbes in breast milk that we didn’t really know about before. And these microbes are also beneficial microbes that are then delivered to the child along with in the breast milk. So that’s another way of colonizing them.

But that said, you know, people have mastitis. Sometimes breastfeeding doesn’t work. So again, I would counsel people to realize, ‘OK, well, I’m not breastfeeding. That’s OK. There’s a lot of bottle fed kids that are perfectly healthy people in this world. It’s not bad, but just try and populate them if you can.
You know, just close exposures to skin, for example, because breastfeeding, you pick up a lot of the mother’s microbes on the breast, and this is really important for colonizing the kids. So hug your child. If you’ve got to bottle feed them, give them a good wet kiss on the mouth when you’re done like most mothers would do and that will transmit. Another thing, in some cultures women pre-chew through their food, they masticate their food, right? And they give it to the kid. Well, that’s a great way of putting the mother’s microbes right into the kid’s mouth. And that’s a good thing, too.

Rachel Cram – You know, when you’re talking about being right up close with your kids, skin to skin contact, the science of attachment, which is a huge part of developmental psychology, it also addresses the importance of skin to skin contact between caregivers and infants as so important to a child’s ongoing growth and development.

But, until this moment, I hadn’t actually thought about attachment, from the microbial point of view, that we’re attaching to each through sharing our microbes.

Dr. Brett Finlay – That microbial transfer. Yep, I mean, when you kiss someone, you transfer 80 million microbes. I don’t know if this is lip kiss or french kiss or whatever the study didn’t get into these kinds of things.

Rachel Cram – That sounds like a good kiss.

Dr. Brett Finlay – Yeah, there you go. But there’s no doubt the closer the contact, the more chance you have of transmitting your microbes. I mean, you could tell who lives in a house with whoever else based on their microbial composition. There was a study they did in some islands in the South Pacific, where they could tell who is married to who by just looking at their microbes because your microbes are gonna be more similar to the person you’re living with than someone that’s like an identical twin living elsewhere.

Rachel Cram – Because you’re in the same world with your family or friends, swapping microbes.

Dr. Brett Finlay – Yeah, so it’s environmental acquisitions. So think of who you kiss, right? Choose wisely. Is that on the dating apps, you know, do you have a microbe test?

Rachel Cram – That would be a new part of Tinder and these dating apps?

Dr. Brett Finlay – Exactly, exactly.

Rachel Cram – Oh, well, I think right now you had to put out if you’re vaccinated or not. So, who knows what they are going to add?

Dr. Brett Finlay – Microbe profile.

Rachel Cram – Yeah.

Musical Interlude #2

Rachel Cram – Well, while we are on the topic of kissing and licking, if we want to take it that far, and I am going to because that’s my pivot, you write about dogs being a wonderful addition to the microbiome of kids and families.

Dr. Brett Finlay – Well, in terms of pets, dogs are the best microbial spreaders. I mean, what does the dog do? It runs around outside, rolls in the dirt, comes in and licks the kid like crazy and the kid licks the dog like crazy. There’s slobber everywhere. There’s hair everywhere, there’s dirt everywhere. This is perfect for microbial transfer.

Rachel Cram – What about cats?

Dr. Brett Finlay – I apologize in advance to the cat lovers out there.

Rachel Cram – I am a cat lover. I have to say.

Dr. Brett Finlay – I’m sorry, they’re too clean. They don’t transfer very much. They’re not in there like dogs are, in your face and I think this decreases the transfer. So if you have a dog in the house, you could drop your asthma rates by about twenty-five percent.

Rachel Cram – Wow, that’s so interesting because I’m pretty sure I’ve heard one of the things people sometimes suggest when children have asthma is not having pets.

Dr. Brett Finlay – Right.

Rachel Cram – So you’re saying the opposite.

Dr. Finlay – Yep. All the studies show that having a dog in the house in early life decreases your chance of getting asthma because of microbial exposures.

So we can detect about 80-90 percent now whether kids will get asthma just by looking at the microbes in the kid’s feces at three months. The first three months of life are absolutely critical for establishing your microbes because they shape how the immune system develops. So it’s that early window because the microbes are training and educating the immune system and if they don’t have those good microbes, it gets pushed to a more, let’s say, asthmatic allergic type direction and then later in life you have much higher chance of getting asthma.

Rachel Cram – Well, and that’s very worrisome for parents because it puts us in the driver seat in a sense, when we don’t necessarily feel ready to drive. And I know that’s why you wrote your book.

You’re giving parents these pointers on preserving their child’s microbes. Vaginal birth, breastfeeding, having a dog or pets, and then we think about antibiotics. You were mentioning how the discovery of antibiotics has saved so many lives, yet, at the same time, antibiotics are slaughtering millions of microbes that our body needs.

So here’s a question for you Brett. If our child needs to take antibiotics, especially before they are 3 months, what can we do to counteract that? Like, is there a pill or syrup of some sort to help get those lost microbes back?

Dr. Brett Finlay – Not yet but we’re getting close. So the question is, “OK, I have to treat antibiotics to save the kid’s life,” which you should do, of course. “What do I do about the kid’s microbes?” and right now there is not a good pill you can give.

But again, give them a good microbe exposure. Hug the kid, let them get dirty, play with the dog, other kids. Try and get them colonized again and let them try and repair the microbes.

We are going towards a pill but we’re not there yet experimentally. It’s coming, but it’s not here.

Rachel Cram – How far off do you think we are?

Dr. Brett Finlay – I would guess five to ten years. Some of the trials are starting now. We’ve identified microbes we know these kids have to have and it’s going to be slow because putting live microbes into a newborn baby is a very scary clinical trial. I mean, you could put them into university volunteers, then you’ve got to work backwards, get them younger and younger, and newborns, as you know, you know, do no harm kind of thing. You worry about that. But I think it will come. We will have a next generation of probiotics. Your kid will be born. You’ll take a blood sample, you will sequence the kid’s genome and then you also do a feces sample. You’ll sequence the kid’s microbes. And you’ll say, “Based on these kid’s microbes, we need to think about doing this,” and then pushing them in that way.

Rachel Cram – Hmm. If you go into a health food store, there are rows and rows of probiotics. Are you pro parents giving their kids probiotics?

Dr. Brett Finlay – Yeah. Well, probiotics. First of all, they don’t harm you. So if you take probiotics fine, they’re not going to hurt you. But the problem is they’re not regulated like drugs, so there’s very, very little clinical proof that probiotics do anything of use. There is a site called probiotic chart.ca, I think. Just Google probiotic charts. And there’s one for the U.S. too, where they list all the probiotics in Canada and what they are and how many you have to take. And they actually give you an idea of what’s the clinical evidence of them working for this type of disease.

Now some things they do work for; 1/ if you have antibiotic associated diarrhea, so if you have diarrhea following antibiotics, there are some probiotics that have shown promise there. There’s a yeast that works for C. difficile. But the analogy that I take is, OK, I need a new pair of running shoes. I walk into a sporting store and there’s an entire wall full of runners and there’s squash shoes and court shoes and joggers and hikers and basketball shoes. You don’t just grab the cheapest pair and then say, you know, “OK, I’m done, I’ve got my runner.”

And this is similar to probiotics you would need to tailor them directly for a specific effect as opposed to a general health promotion.

Rachel Cram – Ok, that’s a good analogy. So, you’re saying, like with shoes, there is no cross trainer yet.

Dr. Brett Finlay – That’s right.

Rachel Cram – That works. You know, out here in parentland we need these kinds of analogies because the science sometimes is very confusing.

Dr. Brett Finaly – Yeah. Oh, and the other problem with probiotics is that the microbes are usually not from the gut. So many are lactobacilli, and you’ve probably heard of these, these are actually from the women’s vagina, and a woman’s vagina is a completely different world than in your intestine. There’s air there, the ph is low, it’s acidic, and it’s the exact opposite inside the gut. There’s no air. It’s very basic down inside the gut. So that’s why you have to take ten billion of these things a day because they just get flushed through you. They don’t stick and colonize.

So I know I’m kind of down on probiotics now, but I’m also really excited about next gen probiotics or probiotics 2.0. We are going to have really cool mixtures of 10-12 microbes that are from the gut there for the gut. You will put this community in and have defined biochemical output that’s going to fix this disease. And I’m working with companies that are now in phase two and three trials where instead of taking a drug, you take a mixture of microbes to treat a particular disease and it’s being regulated through the FDA as a drug. And these mixtures will be proven to work clinically and then I think you will see a lot more of the probiotics. So the bottom line is; probiotics, they’re not going to hurt you. If you like them, go ahead. But there’s very little clinical evidence to say that they do much because they don’t stick and they usually just die inside the gut because it’s so different than where these bugs usually live.

Rachel Cram – Okay, thanks for that explanation on probiotics Brett. So after our child’s had a dose of antibiotics, or we’ve had a dose of antibiotics, you’re saying we’re better off to hug, play with the dog, go outside, so, these options are more effective than probiotics?

Dr. Brett Finlay – Yeah, I tend to say that. And like I say, there are some instances where some do work, but it’s very small.

Rachel Cram – OK. Now I’m wondering Brett, just to fill out this breastfeeding section a little bit more of the second part of your book, you talk about sterilizing bottles, some of the things that we’ve traditionally done, believing that this was an important part of perhaps what you call the hygiene hypothesis. So we’ve done things like sterilize bottles. What do you say about that?

Dr. Brett Finlay – You’re right, this is our history coming through again. The reason you sterilize bottles, you’re worried the kid is going to get an infection, but thrown through the dishwasher, that’s clean enough, you don’t have to boil them. You don’t want them filthy, dirty, growing mold and things, I don’t think that you want to do that. But yeah, I think, the concept that cleanliness is next to godliness, you don’t have to be that clean.

Rachel Cram – You don’t have to be that clean. Ok, while we are in this baby department, what else would fall under the hygiene hypothesis? Where else might we be misinformed as parents of infants when it comes to microbes?

Dr. Brett Finlay – Yeah well, you know, formula, for example, when I was growing up, the ads were, ‘formula is better than mother’s milk.’ But we now know that formula is an approximation of breast milk, and it’s missing many of the ingredients and microbes that you see in breastmilk. So, still in many countries, it’s cool not to breastfeed. It’s a sign you’re wealthy enough to buy formula. And now the pendulum is starting to swim away from that and get back to breastfeeding, and it’s nice to see the swing back in society.

Rachel Cram – Society is always changing with the science. Whether we want it to or not. Continuing on with your theme of Let Them Eat Dirt, what do you suggest for when our child’s soother or a pacifier falls on the floor?

Dr. Brett Finlay – My favorite study? Yeah, we found this when we were writing the book, and I thought it was just terrific that, OK, you put a soother the kids mouth. What does the kid do? They go pop. They pop it out right away, right? That’s the first thing they do, spit on the floor. And this is a fun game. So you look at the soother, what do you do? Well, there was actually a study that looked at your options are; do you run to the washroom, wash the soother off and put it back in the kid? Or you just stick it in your mouth and stick it in the kid’s mouth? And they looked at what happened to these kids over time, and as you can predict, when they put it in their own mouth and back in the kids mouth, those kids had less incidence of asthma and obesity and many other diseases then when you’ve run and sterilize it and then put it in, so. So I’m a big fan of instead of the ten second rule, the three hour rule. You do want those microbes and that’s a great way of getting it. So spit on the child, they’ll love it. It’s good for them.

Rachel Cram – Well, maybe you’re just putting it in your mouth to get off all the dog hair from the dog.

Dr. Brett Finlay – Well dog hair is good, too. There’s lots of microbes on that, too. So, yeah, I think it really illustrates the concept, this maternal to child or paternal to child microbe transfer that’s so important for these kids?

Musical Interlude #3

Thanks for listening to family360 and our conversation with microbiologist, and author Dr. Brett Finlay as we dig into his best selling book, Let Them Eat Dirt.

Our next episode explores Perinatal OCD. When pregnant with her first child, Dr. Shahana Alibhai found herself floundering in ways she recognized but never anticipated. In this interview she describes what it felt like to have her world close in with her anxieties and how she worked to open life back up again.

And now, back to Brett Finlay and another down to earth description of how we help our children care for and consume important microbes.

Rachel Cram – OK. So still, in the section on the first years of life, you also talk about introducing infants to solid food. So they’re done with the breast milk stage, or they’re starting to end it and they’re moving into eating solid foods. What do we want to consider in that process when it comes to our microbes?

Dr. Brett Finlay – Well, solid food is one of the best microbe experiments you could do because any parent that has started a kid on solid food has seen the experimental results out the other end. The feces change. It’s gone for the sweet smelling stuff, to this god awful mess that, “You change the diapers tonight.”

Rachel Cram – Well, and the colour changes too.

Dr. Brett Finlay – Well, that’s cause you changed the microbes.

Rachel Cram – It goes from green to brown.

Dr. Brett Finlay – Yeah, absolutely. And that’s because you’ve put in a whole new collection of microbes that are now living off this solid food. And that’s just a read out of what’s happening in the kids gut when they go from a milk fed, lactose based diet to this complex diet.

Rachel Cram – Is there an optimum time to make this diet shift and introduce solid foods? Is there an ideal time for the microbes?

Dr. Brett Finlay – Yeah, so introducing solid food is tricky. There’s a window there. So when you’re born, your gut is quite permeable. And if you introduce solid food too early, it seeps through the gut and then starts to trigger food allergies.

Rachel Cram – What would be too early?

Dr. Brett Finlay – Well, the sweet spot is four to seven months for solid food. That’s what the current guidelines are. By about seven months or so, if you haven’t fed them solid food, the immune system is developed so much that now it starts to see the solid food as foreign instead of being part of my life, and then you react to it, and that also triggers food allergies.

So four to seven months is the sweet spot and ironically, for a long time, they said, “Do not feed your kid peanut anything, you know, for the first three years of life, you trigger peanut allergy.”

Then they looked over in Israel, and Israel was giving these newborn kids these peanut bars basically that are just ground up peanuts, and Israeli kids had no peanut allergies. So that’s when the light went on; realized that just like other foods you want to introduce your kid to eggs and peanuts and stuff, in that four to seven month window, because then you will tolerize them to it. They say, “OK, peanuts are part of my world. I’ll be seeing them later in life. So that’s OK. We’ll just remember peanuts aren’t bad and won’t get allergic to them.”

So, we learned a lot in that study. It’s funny how science goes from these, never eat peanuts to now put peanuts in kind of thing as we learn more. But that’s the scientific process.

Rachel Cram – That can make it very scary for parents, particularly if they themselves have a peanut allergy. Do you need to have sort of an emergency set up around when you do that?

Dr. Brett Finlay – Yeah, definitely talk to your physician or your pediatrician before you’re going to do this if you are allergic to peanuts. For sure. But most of the allergies, they’re not usually genetic, they’re usually environmental. So if you’re allergic, your kid may have a higher chance of potentially being allergic, but it’s just how you were exposed originally, and your kid may or may not develop them.

Rachel Cram – Are there any foods that are particularly wonderful for bringing in great microbes?

Dr. Brett Finlay – Ah, diversified I think. Some people will say that fermented foods have more microbes in them. That might be, you know, a good thing to do.

Rachel Cram – What do you think about that?

Dr. Brett Finlay – Yeah, I think there’s some truth to that. Kimchi and sauerkraut and stuff like that. But I don’t know. I have yet to meet a four-month-old who likes sauerkraut. I know many adults who don’t even like sauerkraut.

Rachel Cram – So maybe in the Ukraine.

Dr. Brett Finlay – Yeah.

Rachel Cram – OK. Well, speaking of foods that children don’t really take to eat, like sauerkraut, your writing partner Mary Claire, I know in the book she has a story that she told her children to get them too.

Dr. Brett Finlay – Zoo.

Rachel Cram – The Zoo Story, yes.

Dr. Brett Finaly – It’s a great story.

Rachel Cram – Yeah. Do you want to share the story? Because I think often as parents, you can think, “Well, my child won’t eat this. How do I get them to?”

And I think this story was helpful.

Dr. Brett Finlay – Yeah, that was the idea. I co wrote with a postdoc of mine, Claire Areata, who’s a young mother and she knew how important microbes were. She was working on them but her kids refused to eat vegetables and she was just at her wits end. How do you convince a kid that they should eat broccoli and lettuce and stuff.

So Claire gave a lot of thought to this, and then she basically came up with this story that she told her kids that, look, there’s a zoo living inside your tummy. You can’t see them, but there’s all these pets in there. And if you’re good to these pets they’ll be good to you, but you have to feed them every day. But they only eat lettuce and broccoli and carrots. So you have to feed your pets or they will die. If you eat your broccoli and your carrots and your lettuce, you’ll feed these pets and they’ll be happy and make you happy, too.
And it’s a beautiful story. It works. Many, many parents have written to say, “Hey, I’ve actually got our kids eating the vegetables now.”

And the reason this is important is, yes, nutrition, but it’s also important because, as I say, that things in plants, fruits and legumes, these are complex molecules that we actually don’t break down as humans, but we rely on the microbes to do it. And by eating these things you select for the microbes that break these things down and they ironically produce something called short chain fatty acids, they’re really good for us, and so then we get the benefit from that.

So, yeah, tell your kid, you got a zoo in there and the pets got to be fed every time at dinner and they only eat vegetables, otherwise they will die a screaming, horrible death if you don’t feed them. I don’t know.

Rachel Cram – I sense a children’s book coming on. I think that could be your number three bestseller because I know you’ve got two so far.

Dr. Brett Finlay – We thought of that. We thought of that.

Rachel Cram – You should do it.

Dr. Brett Finlay – Cool.

Rachel Cram – Well, returning to Let Them Eat Dirt, in the middle of your book you write about lifestyle issues, some of which we’ve already talked about. I’d love to ask a few more questions on that, and then move onto the last section of your book about how specific diseases are growing “in leaps and bounds,” as you say, and the microbes that seem to affect those diseases. And then Brett, we can look at COVID and see what you have to say.

Dr. Brett Finlay – Great

Rachel Cram – So Brett, I’m wondering, are there microbes that are more prevalent in certain conditions, like are there certain microbes that you have in the country versus certain microbes that you have in the city?

Dr. Brett Finlay – Yes, there’s a big difference in microbes in the country versus the city. And what we realized in the urban setting is the microbes are actually not all that good, the country’s much better. In the city, we all are rather homogeneous in our microbes, we’re kind of similar. We don’t have the diversity you see in the country. And urban microbes are generally not all that good compared to countries. So yes, take your kids out to the farm because exposure to those microbes is much better than the city microbes.

Rachel Cram – OK. Thinking about microbes being everywhere. Assuming that they’re also in the water, is that true? Are microbes in the water? Of course they must be.

Dr. Brett Finlay – Microbes are everywhere. There’s microbes everywhere. Yep.

Rachel Cram – OK, so you were talking about 100 years ago, a thousand years ago. Is there a difference between bathing in a lake and having a sudsy bubble bath? Do you have a thought on that?

Dr. Brett Finlay – Mm-Hmm. Of course.

Rachel Cram – Is there a better or worse?

Dr. Brett Finlay – Yeah, go to the lake. I mean, the bubble bath suds are going to be killing the microbes. Often I’ve wondered what happens when a kid defecates in a swimming pool. That must be good for the pool of microbes, right?

Rachel Cram – And yet we all have to get out of the pool at that moment.

Dr. Brett Finlay – Yep. Turd alert. Got to leave now. Out. Red fire.

Rachel Cram – Oh, that’s interesting because I’m always so frustrated when we’ve driven to the swimming pool and you get in for five minutes, then you all have to evacuate. Okay, so that should not be happening then, is what you’re saying.

Dr. Brett Finlay – Well, I don’t know, but I think, you know, wherever you have people who have defecation, you’re going to have microbes. You always hear about the fecal coliform counts, you know, on swimming. That’s just the number of microbes. That indicates fecal contamination. The reason they make that a warning is that it could also be dangerous microbes, like pathogenic e coli and salmonella. That’s why they close the beaches to fecal coliforms. It means there’s fecal contamination. And I think that should be, “Green flag up. Let’s go swimming guys. Pick up some microbes.”

Rachel Cram – Eww. I know I’m being a microbe whimp, but that is kind of discusting.

Dr. Brett Finlay – You’ll never be the same Rachel, I’m sorry.

Rachel Cram – No, you’re educating me. That’s what I’m here for. I’m here to listen and to learn. Thinking of my youngest child who is not yet a fan of having baths and showers.

You’re mentioning the microbes could die in a soapy tub. Is that an argument for our children who would prefer to pass on their bath time?

Dr. Brett Finlay – Well, we didn’t evolve taking showers everyday. Even back in the 1800s, no one had baths, and they all had powder to cover up the stench. So this is new. And there are studies showing that, you know, every time you shower, hot shower, with lots of soap, you do get rid of most of the microbes on your skin. The problem is, that sets you up for bad ones crawling in because the good ones aren’t there and there’s more chance of getting skin infections.

The general concept of microbiology is that we are actually too clean. And same with using antibacterial soaps. We usually say, “Soap and water before dinner to get the dirt off and other than that, embrace your microbes. They’re good for you.”

Rachel Cram – As you’re answering that, I really appreciated in the book how very careful you are with the science, because I imagine there’s probably a temptation to create a somewhat sensationalized answer to some of these questions that would make parents go, “Oh, you’re got to read this book.” But you are very careful.

Dr. Brett Finlay – We fought the publisher hard on this, and they kept pushing to say more, you know, go out on a limb, we’d say “No.”

So what we were very careful with in this book is it’s where the science takes us, and it’s only based on the science. So there is no hyperbole in here, because there’s so much in the microbiome field right now, that’s all hype and speculation, and it’s very cool, but there’s no data to back it up. So the stuff in the book is based on what we knew at that time based on all the science we had.

Rachel Cram – I think that’s very important to note.

Dr. Brett Finlay – Yeah.

Rachel Cram – Ok, I have a few more microbe lifestyle questions. I think it was in the book, maybe it was in an article I read of yours, you talked about brushing your teeth three times a day, being more effective than even brushing your teeth twice a day in what measured out to be our chances of having Alzheimer’s.

Dr. Brett Finlay – Right, right. So this is in the other book on aging, where you get into this, with the idea of brushing your teeth. And so, yes, if you remember anything from this podcast, remember to brush your teeth three times a day, because what that does is it’ll drop your chances of Alzheimer’s by about 50 percent. And you say, “What does brushing teeth have to do with this horrible brain disease?”

Well, what happens if you don’t brush your teeth you have bad oral health, and then there’s basically holes in your mouth these microbes are going to seep into and they go into the body and trigger what we call inflammaging of the aging process that basically causes all these tissue damage, including damage to the brain, which then increases your chance of getting Alzheimer’s. And people always ask the next question, “Well, what about flossing my teeth?”

Rachel Cram – I was about to ask that.

Dr. Brett Finlay – Well, I didn’t do that in the study, so I can’t answer that one.

Rachel Cram – Fair enough.

Dr. Brett Finaly – But that definitely increases oral health and oral health is good because it prevents the microbes from seeping into the body. So. So probably. But there was no study.

Dr. Brett Finlay – OK, Brett, I want to jump with you into the fifth section of your book. In the latter half, you talk about specific diseases that are growing by leaps and bounds in our society, you say, and the microbes that seem to affect them. There’s particular diseases that you mentioned quite frequently, asthma, obesity, diabetes, heart disease, you can jump on board and say, what else adds in. I’m wondering, are they almost something we can consider contagious now in a unique way because of how we’re understanding microbes?

Dr. Brett Finlay – I’ll pay you later. That’s a great question. So I wrote a piece for Science, which is a very famous journal in our field and the title of it was, Are Non-Communicable Diseases Communicable? And so when I say communicable diseases, those are infectious diseases. That’s like colds and diarrhea and things we know are transmitted from person to person. But noncommunicable diseases are things like asthma and obesity and diabetes and inflammatory bowel disease. And what we’re starting to learn is that microbes play a major role in these diseases that we just previously had no clue about; cardiovascular disease, for example.

So if you take the top ten reasons why the average Canadian or American dies, heart attacks, strokes, kidney disease, lung disease. It turns out there are microbes in nine of those ten different diseases. The only one that they haven’t a role in is accidents. So you can’t say, “Officer, the microbes made me do this,” kind of thing. No. Well, maybe they might have an effect on the brain. So we’ve learned all this stuff, these microbes are playing roles we didn’t really know.

Now, what we also know is people with these diseases, they’re microbes are different than people that don’t have these diseases. We call this dysbiotic. But if you take the microbes from the disease people you can actually transfer that disease through the microbes. So you can do this with obesity. You could take, obese people feces, put them into thin mice, the mice get heavier and vice versa. You could do this inflammatory bowel disease. You take, people with IBD put their feces into a mice model. They cause IBD.

So you can move the microbes that way. And then the other thing is that as we’ve talked about living together, you have very similar microbes. So, for example, inflammatory bowel disease, your spouse has a much higher chance of getting IBD if you have it.

So I was half joking when I was saying on the dating app, we should talk about our microbes because in theory, they could transmit the microbes and make it more unhealthy and increase your risk of disease. Now it’s a radical concept. It’s not really been rigorously proven, but there’s a lot of evidence. It’s a smoking gun right now.

Rachel Cram – You’ve also mentioned that anxiety and depression are linked to microbes.

Dr. Brett Finlay – Yeah, probably the hottest area in the microbe field right now is the gut-brain axis. So we know the brain tells the gut what to do. Now we’re arguing, the gut tells the brain what to do in a lot of senses. So if you take an anxious or a stressed or a depressed mouse and you do fecal transfer to a normal one, you will transfer anxiety, stress and depression just through the feces. And that’s profound because we think it’s all these other things affecting these diseases.

There’s a direct correlation with courses of antibiotics and anxiety and depression. The more antibiotics you get, the more susceptible you are to these diseases. So that’s probably the hottest area of research in this whole microbiome field. Are there microbes that affect your brain?

We’re doing a really cool study now here at UBC, where they work on early language development and also music acquisition. And so we’re characterizing the microbes, and I actually woke up in a cold sweat one night thinking, “Oh my God, music acquisition and language, these are signs of intelligence. If we find the microbes, we’re going to find IQ bugs. What are the ethical implications of, “Hey, there’s a bug that help your kids learn languages better or something?”

And I rolled over and went back to sleep and said, “Well, that’s a long time from now.”

We’re not there yet, for sure. But you know, these are the kind of thoughts we’re having now. These microbes are so central to so many of the processes that we just didn’t realize before.

Rachel Cram – Yeah. As a parent listening to you, I can be thinking to myself, “OK, I don’t want my child to have asthma. I don’t want them to have diabetes. I don’t want them to be obese. I don’t want them to have anxiety. I don’t want to have depression.

Can you give five things that parents can do, even without knowing all the science behind this, to best set up the microbiome of their child for success?

Rachel Cram – Yeah, I think the real key message is, think of all that we’ve talked about and incorporate the microbes in your general lifestyle, thinking and planning. Realize that there is this invisible component that plays such a big role we didn’t know about before.

There’s a book called The Blue Zones; five areas in the world where people live forever. Well, when you look at what they’re doing that others that don’t live as long aren’t doing, there’s really four components. The first one is diet. Diet is really important, kids on up. We usually say, “You are what you eat.”

I now say, “Your microbes are what you eat,” which is what then you are.

Diet plays a big role. So it’s all the things your mum tells you to eat and you say, “I don’t like that.” you know. Fruits, nuts, legumes, less red meat, less white flour, less sugar, more complex carbohydrates, more berries, more fish, more olive oil. And that’s been shown to have profound effects at all ages of life, including mental health later. So, diets the big one.

Exercise is also big. So even as you age, you want to be active.

Rachel Cram – How does exercise affect your microbes? Because I think in the past, we’ve heard about exercise because it gets your blood moving. It’s good for your muscles, it’s good for your joints, it’s good for your bones. It helps with osteoporosis. What does exercise do on the microbe level?

Dr. Brett Finlay – It pushes your microbes to a more anti-inflammatory type composition. And as we discussed, inflammation is bad for you. It causes tissue damage and things. So exercise is a way of correcting your microbes, it’s well documented.

Another one is community. So in these blue zones, people, they will have 80 year old daughter looking after 100 year old dad with the great grandkids and the dogs and the cats and everything all roaring through the same house. So these elderly are then exposed to these younger microbes.

I think it’s almost criminal the way we treat elder care in our society. We keep them sequestered, feed them not such great diets sometimes, and I mean, their microbes are hooped then. Where’s the kids? Where’s the dogs? They should have these dogs ripping through these houses with these young kids in tow and they can’t get better microbes. So a sense of community.

And the last one was stress. You want to lead a less stressful lifestyle because stress is terrible for your microbes. It drives them to a very inflammatory, bad situation.

So from a kid point of view, those are equally applied. But I think, good diet, get outside, you know, enjoy the world we live in, get out of the concrete jungle, and get off the screen and get out into the world that we evolved in. Because microbes did not evolve with iPhones and screen time, they evolved to be outside. And if you’re not outside, you’re missing out on a key part of our evolution.

Rachel Cram – That’s a hard message to convince our children of.

Dr. Brett Finlay – I agree, it’s very hard. And frankly, I’m very concerned about the way our world is going because each generation our microbes get less and less diverse and the microbes are disappearing, they’re going extinct. And what I’m really worried about is we’re going to realize two or three generations down the line that, oh my goodness, there was a microbe we really needed, we evolved with, but it’s not here anymore because we’ve cleaned it out of our system. And the way we live, I think it’s going to spell problems down the line. It already is.

Rachel Cram – You make a comment that I think is so positive. You say that only 20 to 25 percent of longevity and healthy aging is genetic, that the rest of it we can change. So that 75 to 80 percent of our health and well-being we actually can control.

Dr. Brett Finlay – Yeah, I’m glad you picked up on that, because really, I think that’s the biggest thing about aging. Twenty percent you can blame your parents, you can’t do anything about. But if you can control 75 to 80 percent of how you age, it’s thought you can add at least another decade or so of healthy living to your life, just by lifestyles and environment. And whenever I say environment, of course I’m saying microbes because I see the environment as basically, this microbial interface with our world.

So, yeah, I think there’s a lot that can be said about all stages of life if you incorporate the microbes into the whole concept. You can use it to your advantage. I mean, knowledge is power, right? I have just told you many different ways you could actually improve your life.

Musical Interlude #4

Rachel Cram – It’s so fascinating. And now here we are living in the midst of COVID, which on the one hand, you must see as a tragedy that it is and the other side of you must go whoo research, that you never expected would come your way. As we go through COVID, what are you thinking?

Dr. Brett Finlay – Well, you’re right. Woo-Hoo. This is the coolest experiment ever. When else can you shut the entire world down and see what happens? As a scientist, it is a fascinating golden time to do all sorts of interesting things. In terms of an effect, I think the bookends of life, early life and late life, because that’s when the microbes have the biggest influence. And frankly, I worry about what I call COVID kids, the ones that were born during COVID because they’re not going to preschool, they’re not encountering other kids, they’re not traveling, so there’s some concern there. On the other hand, maybe they’re spending more time with their parents, so that’s good for them. There’s arguments, both ways there.

Rachel Cram – Good from an emotional state, but not necessarily from a microbe state.

Dr. Brett Finlay – Yeah, that’s right. Yeah, yeah, I think we’ll probably see a bump in asthma and obesity because these early life microbes are screwed during COVID, and we’re going to see the end results in another five years of that.

But yeah, this is a real tension between, you know, hygiene and microbial exposure again. And just up until COVID, you know, I was preaching, “Eat dirt. Get your kids out there. Don’t worry, the world’s pretty safe, get your microbes.”

Then COVID came along and suddenly we’re back to the late 1800s, where the only way we have to stay safe is quarantine and hygiene and don’t see anyone else. Don’t put your head outside the door. So we’ve regressed significantly in terms of our attitudes towards this. So I don’t know where this is going. I do hope that there will be an end to this. But I do think again, our behavior will be altered permanently. And the good thing is, everyone now knows what a virus is and how microbes are started to work. So, that’s good in that sense.

Rachel Cram – You’ve talked about antibiotics and carpet bombing microbes and needing to be really careful with that. Now I know this is a divisive topic for some, but what are your thoughts on vaccines?

Dr. Brett Finlay – Get your vaccine. Get them, I mean, these are a huge medical improvement. When you look at the numbers, vaccines are extremely efficient. You know, we don’t have smallpox in our world anymore. We don’t have polio in our world anymore.

I strongly believe in vaccines. They’re safe, they’re effective and they’ve gotten rid of some really horrible disease. They’re the biggest reason we’re actually talking today because if we didn’t have vaccines we’d still be talking about why all these horrible diseases are ripping through our society.

So yeah, every year when flu shots come up, we have a shot party. So my wife, who’s a pediatrician, she brings home a flu shot and we take a thimble of tequila in one hand and a needle on the other end, and one for the arm and one for the hatch and life’s good.

Rachel Cram – Oh, you guys are so romantic. I love it.

Dr. Brett Finlay – Oh, you should see us.

Rachel Cram – OK, well, Brett, we have been talking for a long time and I know we have to start to wind down. I’m just wondering if we can end our conversation with how you end your book, which is talking about the future. Do you have grandchildren yet?

Dr. Brett Finlay – I just have two. Yeah, our second one a couple of weeks ago, so very much so.

Rachel Cram – Oh, congratulations. That’s exciting.

Dr. Brett Finlay – Well thank you. Yeah. What can I say?

Rachel Cram – So when you think about your grandchildren then, if I can use them, what would be your microbial dreams for what we can see in the future?

Dr. Brett Finlay – Yeah, I think there’s a huge amount of promise here for a healthier, better life for my grandkids just knowing we know about microbes. I strongly believe that very soon in the future, as we discussed, once you’re born, you’ll have your microbes analyzed and your genome. And based on that, there will be some personal tailoring to allow you to then make sure you don’t go towards obesity and diabetes and asthma and things like this. So there’s excitement there.

I think probiotics will be a whole new world of real drugs that work really nicely using microbes that will fix us. I think that as they go through life, our microbial knowledge will really help them actually age much better.

So I honestly think that this is a whole new chapter of medicine that we’re just starting to peer into now and realize there’s huge implications in so many different areas of medicine that it’ll make the world much better for them. So I’m optimistic in that sense. So yeah, I think microbes will be a whole new way of medicine that we really hadn’t thought of before.

Rachel Cram – Well, Dr Brett Finlay, Sir Brett, I thank you so much for your time and your conversation today. This has been really fascinating. And I am just going to go and eat a varied diet, with lots of vegetables and perhaps some sauerkraut for my lunch today.

Dr. Brett Finlay – You’ve got it. All right. Great. Well, this has been fun. So thank you so much.

Roy Salmond – Thank you Brett.

Dr. Brett Finlay – Yeah, it’s been fun Roy. Glad we got to work. Alright, see you guys. Bye.