How to keep kids healthy
This interview is from A Kids Book About: The Podcast, with host Matthew Winner and author of A Kids Book About Your Microbiome, Ara Katz. It has been lightly edited for clarity.
What is your microbiome?
Your microbiome is the collection of microbes, which are little microorganisms way too small to see with the human eye that exist in a specific ecosystem. That's the collection of that and not just microbes themselves, but also their genes. There are structural elements, the things they produce, which we call metabolites, and also their surroundings. And all of that forms this unique ecosystem.
Now that could be in on a coral reef and it could also be in as we'll talk more about today in your stomach and your mouth to be in a rainforest. It could be in the desert.
And so each ecosystem, and even on your own body, ecosystems are really different. And so your microbiome, when you talk about the human body, is referred to as all of the microbes and all those parts combined. But actually even within your microbiome of your body, there are smaller ecosystems that have their own microbiome, which is really exciting.
Even though scientists and researchers have colored the images in order to help our eyes to better distinguish what we’re looking at, your microbiome still looks like a completely different planet! And are they part of your body?
They're technically separate. They're not human, they're microbes. Just to qualify the term so everyone can understand what a microbe is, they're single-celled organisms that most like in our bodies, like primarily bacteria, but also viruses, protozoa, phage, and other microbes make up your microbiome.
So a lot of people think it's just bacteria, but actually there's other types of microbes, but they are not human. However, they have co-evolved with us over many, many, many, many tens of thousands of years. And so we are seeded them at birth.
And then in science, there's a lot of controversy over how early our microbiome even begins, because some people think [the] embryo has exposure to certain microbes or things that shape your microbiome even before birth. But what we do know is that the motherload of your microbiome is seeded at birth, no matter how you're born. And so that is where you're kind of seeding process and your microbiome develops, but that came from your mom. That comes from the mother.
And so we have co-evolved with them, even though they are not human. However, many of our human functions cannot be done without them.
So when Ara mentioned before that these microbes have evolved with us over this time, this is exactly what she’s talking about. They are made for human-to-new-human transference! That means they are transferred, or passed on, from one generation of humans to the next.
And they work in symbiosis with our body. I think a lot of kids in school learn about clownfish and anemones. You know, specific fish that eat plankton or skin off of like a whale, for example.
These are examples of symbiosis in nature, but actually like symbiosis, it happens between our microbes and our human body.
And there's many things too. I mean, they do incredible things in our body and they're a huge part of your immune system. Knowing part of that, or those early years of seeding, is part of them training your immune system of—is this good for me? Is that for me? Should I have an allergic response? Should I get sick? Is what's coming in good?
And so there is such a big part of your body knowing, like, is this helpful or is this harmful to me.
Our microbiome is so incredible!
But now that we know how all of those microbes get started in our bodies, back when we are in the womb or just being born, I wonder how they keep going? Like, what’s their main goal?
The way I might think about it is that what microbes want to do is that they want to persist and they want to replicate.
And if you're the host that they depend on for a nice place to live and a steady nutrient supply, then they are interested in keeping you, their host, healthy. If you can think about it that way.
I’m kind right in the middle here. It’s wild to think that so many things are happening in me that I don’t directly see or feel. But it also feels really amazing to be a superorganism and to feel this wonder about my microbiome.
I will say that when you understand the microbiome, when you understand this non-human part of you, which by the way, just to put it in also some numbers and some sense for people:
About 50% of your body by cell count is not human.
And they express more genes than your human genes too, which is really interesting. There's estimated [to be] about 38 trillion bacteria. And therefore, if you added in the viruses and the phage, some of the other microbes, you're at multiple tens of trillions of microbes, which is incredible.
So when you ask me how I feel, I really do feel grateful. And I also feel grateful for the perspective of understanding this part of my body that does this important work because it then factors into the decisions I make every day and how I consider and make choices both for myself or my son.
Does having too much of those good things make a difference? Does it hurt me? Or does it help me more?
That's an amazing question that I've never gotten because most people, most adults, ask, “Do I have enough?”
There's so many things that probably more adults have done more in their lifetime than kids that can really impact the microbiome and actually make it very, not diverse and also deplete it.
Like antibiotics, because antibiotics basically go in and kind of like bomb your microbiome. Cause that's what their job is, right? Cause they're trying to get rid of a negative, a bad microbe, but they're not like heat-seeking missiles that only find the bad microbes. They kind of clear everything.
And so a lot of adults are very sensitive to that because there's a lot of conditions that adults suffer from that have to do with having microbiomes that actually have either had too many antibiotics or have what they are, what they call dysbiotic, which means that they're kind of like out of whack, out of balance, or low diversity.
So in terms of the question of too many, the truth is I don't know, because [of] our problem in modern life. It is the opposite. And so much of the research is actually looking at cultures where there was so much greater richness with like, abundance of microbes and diversity.
So I imagine that there's probably a tipping point, but I don't know what that is because you can't really introduce microbes and have them stick around. It's not how, if you take what's called a probiotic for.
A lot of people think you take a probiotic or you eat a lot of things that have microbes in them, like fermented foods or kimchi or kombucha.
And somehow the microbes stick around, but actually microbes are kind of transient. Which means that they do what they're going to do in your body, but they do it on the road on their way out. On their way through and then out. And so, I don't know, because I wouldn't know how you would actually implant and put a ton of microbes in somebody.
But I would say, the best way to think about it is that right now, one of the most important things is that people do think about how you want your microbiome to look more like a rainforest than a desert. And I think the problem today is that not the people who have too much, but actually trying to figure out how we get back to a place where we have more rainforest than desert, because a rainforest is so much more resilient than a desert—which is not going to be able to do all the important work that a lush rainforest or a dense rainforest could do.
Actually, the things going on at Seed Health are pretty incredible. Microbes can be found everywhere throughout the entire planet, not just in and on humans, but on almost all other living things, and even in the most extreme places on earth, like in hydrothermal vents and in ultra acidic pools and in extreme depths of the ocean and even in the coldest parts of the arctic.
And so if microbes are everywhere, it makes sense that Seed would look beyond our bodies in their work as well.
So we work only in the invisible world. We are not invisible ourselves, just to clear up that misunderstanding. And we don't have super powers to make ourselves invisible, but we do try and unlock the superpowers of the invisible world to figure out how we can use microbes.
Primarily the ones that you do find in the human body or native to specific ecosystems like in honeybees or in coral reefs and how you can use those microbes to make an impact in health. And so I'll give you a great example. We have a probiotic that we created for honeybees and honeybees have their own gut microbiome and honeybees are incredibly important to our food system, to our environment and honeybees are dying.
And what we've found out is that pest specific forms of pesticides hurt the honeybee microbiome. And remember I said that so much of your immune system is in your gut micro. So honeybees don't have the immune resistance, their immune systems aren't super strong against the effects of these pesticides.
And so they get things called colony collapse disorder, or even worse. The larva gets something called American full bird disease. So if you give honey bees in the hive a probiotic, you can help their gut microbiome and their immune system have more resilience against the pesticides and they can survive.
And so now the real intervention would be, let's not use pesticides. But knowing that we're not going to change, that we are trying to figure out, well, how could you help the honeybee microbiome to be stronger and more resilient so that these aren't dying as quickly? So that's a great example for humans.
We use probiotics and microbes to do things in your gut microbiome, just to stay on that ecosystem. How could you take a microbe? For example, we have a kid's probiotic coming out, and the question is, so how could you take a microbe and help that microbe [in] kids, for example, that have trouble pooping? A lot of microbes are involved in diet digestion in your gut, and they're a big part of triggering these muscles that help with these neuro-transmitters that trigger something called motility.
[Motility] is what helps your poop move along. And so you can take specific microbes that help signal to the specific neurotransmitters, that signal to help poop move along. And so that's what we do is we're always looking at like, how could you take a specific strain of bacteria? We work mostly in bacteria and understand what it could do in the host.
And again, that could be a human, or it could be a honeybee—or it could be a correlation. Or it could be a child. And how do you use that to impact the health of the host?
I can’t believe we waited all the way until this point in the episode to talk about poop! Oh my goodness!
You know what? Why don’t we close our time together talking about poop because, really, what better place is there than at the end of this episode? The end? Get it?
Okay. Alright. Here’s Ara.
A lot of people don't know that a lot of your poop is made up of microbes and that even though a lot of you guys may think poop is gross and disgusting, it is actually like a really important part of knowing what's going on inside. And I know this is going to sound gross. Cause most people don't like to look in the toilet bowl, but what shape your poop is, what color it is [is important].
If it comes out in one piece and lots of pieces, depending if it's hard to get out, is it easy to get out? All of those things are what they call mark, that tell us a lot about what's going on inside and also about what you're eating and your health. And so the next time you look at proof, yes, it may not smell great, but it is something that's really important. From when you're little, you start to see it as also like a pretty important thing to know how things are doing inside.
Maybe you can grow up and not think it's as gross and or think it's as gross and also know that it's kind of important that you understand what it is, what it says. And it's a great way to know if things are not okay, you need to maybe tell a grownup.
Each week on A Kids Book About: The Podcast, we talk about the big things going on in your world with a different author from our A Kids Book About series. This week we spoke with Ara Katz, the author of A Kids Book About Your Microbiome and Co-Founder as well as Co-CEO of Seed Health, where she works with microbes.