The Jordan Harbinger Show - 610: Bill Sullivan | Pleased to Meet Me

Episode Date: January 11, 2022

Bill Sullivan (@wjsullivan) is a professor of pharmacology and microbiology at the Indiana University School of Medicine in Indianapolis, an award-winning researcher, teacher, science communicator, and author of Pleased to Meet Me: Genes, Germs, and the Curious Forces That Make Us Who We Are. What We Discuss with Bill Sullivan: What we're just now learning in the field of epigenetics -- the study of how your behaviors and environment can cause changes that affect the way your genes work. Why twins who are genetically identical look less alike as they age -- or if they've been raised apart from one another. How the overabundance of plastics and other endocrine disruptors in our environment are affecting not only our bodies on a molecular level, but the physical and mental development of generations down the line. How kids -- even the unborn -- are epigenetically altered by the social and economic status of their parents. What we're learning about the role of the teeming millions of microorganisms that live inside of us -- collectively known as the microbiome -- on our overall mental and physical health. And much more... Full show notes and resources can be found here: jordanharbinger.com/610 Sign up for Six-Minute Networking — our free networking and relationship development mini course — at jordanharbinger.com/course! Miss our interview with Find Your Why, Start with Why, and The Infinite Game author Simon Sinek? Catch up with episode 300: Simon Sinek | How to Play the Infinite Game here! Like this show? Please leave us a review here -- even one sentence helps! Consider including your Twitter handle so we can thank you personally!See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Coming up next on the Jordan Harbinger Show. If you take a microbiome sample of intestinal bacteria from a depressed person and put it into a germ-free mouse, that mouse starts to exhibit symptoms of depression. It won't be interested in treats. It won't socialize with other mice. And if you drop it into a bucket of water, it won't even try to swim out like a normal mouse would. So this was a huge discovery that linked. for the first time, something about the human microbiome is linked to depression.

Welcome to the show. I'm Jordan Harbinger. On the Jordan Harbinger show, we decode the stories, secrets and skills are the world's most fascinating people. We have in-depth conversations with people at the top of their game, astronauts, entrepreneurs, spies and psychologists, even the occasional former cult member, undercover agents, or music mogul. Each episode turns our guest's wisdom into practical advice that you can use to build a deeper understanding of how the world works and become a better critical thinker. If you're new to the show or you want to tell your friends about it, we've got episode starter packs. These are collections of your favorite episodes organized by topic that'll help new listeners get a taste of everything we do here on the show.

Just visit jordanharbinger.com slash start. You can find them also in Spotify that'll help you get started or help somebody else get started. And of course, I always appreciate it when you do that. Today, how much of our makeup is because of our genetics? And how much is because of our environment? This isn't just nature versus nurture, but how nurture affects what's already in our nature. I know it's a little confusing, but we'll get through that today and we'll explain exactly why our environment interacts with our genes to make us who we really are. Also, some things we touch or spray on ourselves might mimic hormones and change the way our body and brain works, sometimes in scary ways, and our gut biome and what's in our digestive system

almost certainly affects how and what we think. This wasn't brand new for me, but the science here is really incredible. Last but not least, a bacteria that makes mice attack cats? Yeah, you've heard me correctly. Really fascinating conversation on some subjects that we don't usually discuss here on the show. And if you're wondering how I managed to book all these amazing folks, these thinkers, authors, creators every single week, it's because of my network and I'm teaching you how to build your network for free over at Jordan Harbinger.com slash course.

The course is about developing your networking and connection skills and inspiring others to develop a personal and professional relationship with you. It'll make you a better networker, a better connector, and a better thinker. That's all free at jordanharbinger.com slash course. And by the way, most of the guests you hear on the show, subscribe and contribute to the course. So come join us. You'll be in smart company where you belong. Now, here's Bill Sullivan.

I loved all the 80s references of the book because born in 1980 myself, you have a lot of kind of deep cuts. There's a lot of references in there that I go, wow, okay, I haven't heard that for a hot minute. I'm glad you caught some of those. That's why I put them in, a little Easter egg kind of things, a child of the 80s myself. It was fun to put those in. Yeah, it's kind of like, oh, is that a fast time at Ridgemont High reference or whatever? You know, did you just mention something from Goonies that you would only recognize if you'd seen it in the last few years?

Yeah, some are a little obscure. Yeah, exactly, obscure. I guess that's the word I was looking for. Like, I'm pretty sure that's a quote from Chunk from Goonies. Everybody born after 1984 is like, I have no idea what you're talking about. That was my movie, though. That was like recorded off TV in VHS, rewatch it every month with commercials. The best jokes edited out like when the statue falls and he goes, oh man, that's mom's favorite part because the penis falls off.

Awesome. Yeah, I still have a goony shirt. I mean, it's one of my favorites from that era. The book is very interesting. I don't cover health, but this isn't really health. This is more about how humans are biomechanical machines and we're very different from one another. And yet we kind of don't really know why. Is that accurate?

That's very accurate. And this book encompasses a lot of great stuff. And it just all started with kind of like the virtual reunion that happened years ago when I got on social media and just started linking up with friends who I haven't spoken to or seen in 20 years. And it makes you think your mind goes back to this classroom full of these budding youngsters and all that potential promise in the future. And you see some people are very successful. Some are married. Some are divorced. Some might be in jail.

some struggle with alcohol and drugs, like some are writing books. And you wonder, why? We were all pretty much the same. We all grew up in the same area, the same relative environment. What creates all these differences? And I think that's a fundamental question that many people at any stage in their life wonder about as we try to interact and work with people throughout our lives. How are we so similar and yet so different at the same time? And by learning the answers to those questions, I think we can lead a much happier and healthier life. Yeah, we know that DNA and genes are a lot of the difference, obviously. There's countless books and research on why DNA and genes lead us to have red hair versus brown hair or tall versus short, but the rest of it being environmental and epigenetic is, I think, long suspected, but something that most people didn't really know. And even now, we don't really know what's going on, right? So it seems like DNA itself has many different options built into it. Does that sound right? Well, I'm oversimplifying it, of course, but it sounds like there's different sort of on each strand of DNA and it's not just like this is who you are, there's different layers. I think you hit the nail in the head, Jordan. That's a very concise summary of what epigenetics tries to say as a science. And this is a relatively new science. It really only came to the fore around 20, 25 years ago. Before that, there was a lot of genetic determinism, genes being the recipe of life and dictating exactly who you are. And there is some elements of truth to that. Like you said, many people are comfortable with the fact that genes,

Dictate various aspects of our physical nature, including like hair color, eye color, things like that. But there's a lot more to it than that as epigenetics has revealed. And in a nutshell, what epigenetics is saying, it literally means beyond the gene. What it is trying to convey is going back to this whole divide of nature versus nurture, genes versus environment. And it's basically saying this should not be a division at all. These are two sides of the same coin because the environment actually regulates our genes in real time. That creates this fascinating flexibility.

And it's kind of interesting to think about philosophically. There are multiple versions of who you can be in your genome. And it's the environment that kind of coaxes out the person that you are. It's a really interesting interplay. And it made geneticists think really hard about, about the limitations of genetics. So epigenetics is essentially how the environment affects what our genes express or which genes are expressed, right?

So this is probably a terrible example, but let's say that in cold weather, more people have blonde hair, and I'm making this up, to be clear, then if the person who had that gene that said, well, dark hair in warm climate, blonde hair, and cold climate, if that person moved to a different climate, then their hair would be a different color versus their identical twin theoretically who stayed in the original environment, right? So the environment would flip a different switch on that DNA to create something different in the way that that gene expresses itself. Does that make sense? Yes, it does. And let me unpack that a little bit. You've actually said quite a bit of really cool stuff in that statement. I thought you were going to say nonsense, but go ahead. I'll take really

cool stuff. Well, it leads us to some really cool science, okay? I think an analogy might help a lot of your listeners understand what genes are all about. Because historically, and perhaps in biology class, many people thought of genes as an on-off switch, right? The gene's either turned on or it's turned off, but that's not necessarily the case. Genes are more like dimmer switches or volume knobs, okay, if people remember those. So you can have everything from a very little, negligible amount of that gene being activated to all the way. You know, it could go to 11 to use the spinal tap reference. And that basically, you know, genes build proteins. So the more the gene is turned up, the more the protein is expressed. So in a very crude analogy, you can imagine that if someone in

one set of circumstances expressed a very little bit of serotonin, which is a critical neurotransmitter that controls mood, if they had genes that control serotonin, but they had very low levels of it, but then we put them into a different environment or give them a medication that can alter the expression of that gene, serotonin levels can rise, and then they experience a better mood. I also like what you said about identical twins, because there's been a phenomenon associated with identical twins that has created a decades-long mystery for geneticists. And that's the fact that as identical twins age, as they get older, they look a little different and they sometimes even behave a little different than they did when they were young. And what people need to be reminded of is that

they have absolutely identical genes 100%. They are literally clones of one another. So how can this be? How can people with the same exact genes once they're older in their 40s or 50s start to show differences? One of the most dramatic examples is twins, identical twins that are discordant for obesity, which means one of the identical twins is lean and the other one is obese. How can that be if they have exactly the same genes? Right. This is where epigenetics come into play. And the real quick experiment, I'll resolve that mystery, was when scientists discovered that epigenetics has a say and how much a gene gets turned on or off, they started developing tools where they can monitor this.

It's fascinating technology, right? But they can actually stain chromosomes to identify whether they've been epigenetically changed or not. Oh, wow. So the upshot is, in very young twins, if you look at the analogous, you know, chromosomes and you stain for these epigenetic marks, they're pretty much identical in young twins. And then if you look at older twins, 50 years or older, those epigenetic marks are all over the place. They are not conserved between the twins. Even though the genes are the same,

the song has changed, right? So the epigenetic marks have changed. And that is what attributes differences that we sometimes see in identical twins. It's funny. I've got a pair of identical twin buddies. They're both great people, so I'll caveat because people are going to be like, dang, I hope They don't hear this, but they're both really great guys that I'm close with. One of them is like a health nut personal trainer and the other one used to smuggle cocaine for the hell's angels. Wow. You can definitely tell them apart, I'll put it that way.

You know, not just because of tattoo volume, but because of other very clear reasons. Like, you would never confuse one for the other. I'll put it that way. And a lot of that's environment. Yeah, and it's either physical things that they encounter in their environment or even psychological things. Both of those have been shown to alter genes at the epigenetic level, and we're still discovering new ways that genes can be altered. The analogy that I like to use that seems to resonate with a lot of people is that you can think of your genes as piano keys, but the

environment plays the song. I'd love to talk about endocrine disruptors as well. This is something that, first of all, what are these? Because this terrifies me, apparently there and everything. Yeah, a lot of people are justifiably concerned about endocrine disruptors, and they are everywhere. They're in all kinds of different plastics, and many of them are what we call forever chemicals because they don't biodegrade anytime soon. So once they are put out there into the environment, they're there to stay. And what's alarming about them, as you might surmise from their name, is that they disrupt our endocrinology and the endocrinology of other animals. And what do we mean when we say that? Yeah. It means that chemically, if you were to, for most people, this is a terrifying experience, but you go back to chemistry class and think about those tinker toy models. When you look at chemical structures, the constituents of these plastics, these so-called endocrine disruptors, look a lot like hormones, and they can act on our body in the same way.

Hormones are very delicate molecules, and they are only expressed like during certain windows of time during development, and they're expressed under very tight control. You can't have too much of them. You can't have too little. They have to be just right. They're like a Goldilocks molecule. Endocrine disruptors get into the body, and they wreak havoc with our endocrine system because they're acting like hormones being expressed at the wrong level at the wrong time. I've heard from friends of mine who are kind of health nuts. They're telling me things like, you should get a reverse sasmosis filter for your kitchen because if you're drinking tap water, yeah, you're drinking chlorine and weird stuff from the pipes, which is already gross enough, but you're also potentially

drinking, especially if you live in a city or something like that, you're drinking birth control pill urine runoff type stuff where women who've taken birth control pills and other plastics and things like that that are in there are now in the water. And then I'm chugging a couple gallons of this every day or drinking it in my tea. And it's like I'm taking a small version of those. pills, among other things, and those are all hormones that would maybe be in absolutely tiny, tiny, infinitesimally small quantities in my body. I'm now slamming a thousand times that per day or a hundred times that per day. That's really, that's disturbing. And it's not just birth control pill pee from other people, it's the plastics and the water bottle. Like I remember when I was seven,

eight years old playing soccer, and they would give us these water bottles that stank to high heaven of plastic, and then you'd drink the water, and the water would taste like this toxic plastic, and I would go, this is disgusting. Why is no one talking about this? And then, of course, 10, 20 years later, they're like, oh, those are BPAs. You should be consuming zero of that. They're illegal now. And that was like in every kid's water bottle that we were told, drink enough water, you're playing soccer, drink the whole thing, and refill it. Yeah, this is a major, major problem. And it's a fundamental problem with chemical safety. When scientists put out a drug into the world, they go through very rigorous clinical trials to ensure that it's going to be safe and that it won't cause any obvious harm.

They test this in tens of thousands of people. When someone invents a new plastic, it doesn't go through that. It just goes out there. There's very little regulation that's tied to that and it's presumed safe until proven otherwise, which is a logic that is truly befuddling, especially when you have a chemical that demonstrably looks like one of the chemicals in our body that is required for development and fertility. So this is a major, major problem. There is a wonderful book, a very frightening book, but a wonderful book called Countdown that was released not long ago that describes that the advent of endocrine disruptors being disseminated throughout our plastics and into our environment

tracks almost identically with the dramatic drop in fertility that we're seeing in a lot of countries that utilize these chemicals. There's been some epigenetic data that shows that these endocrine disruptors can interfere with a variety of genes that are linked to fertility. This is one of the major concerns of the endocrine disruptors in addition to potential developmental problems in fetuses that might be exposed to these during pregnancy. It sounds like there's a whole show here. I'll move on pretty quick, but I'm so interested in this because even though I don't cover health, this isn't really one of those things that's like, it's not a fad diet or an exercise plan. This is something that I think is pretty well documented and is not just hype.

The problem could be overstated. I don't know. I haven't done any research, but it seems to me like if every kid drank out of a toxic endocrine disrupting water bottle for a decade playing sports growing up, there's something there, especially if it's still in our drinking water slash air slash food. So one more depressing show to put on the document. it. Thanks, Bill. Well, well, you bring up a good point, Jordan. We don't want to induce a lot of unnecessary fear in people. Yeah. So where most scientists are on this at the moment, the fundamental

principle in toxicology is dose. Nothing's a poison necessarily. It's the dose that's the poison. Take the famous example. You can ingest enough water to actually kill yourself. But water, we don't consider to be a toxin of any kind. It's necessary to live. But it just illustrates the point that everything can be a poison if it's at the right dose. So what you say, say is critically important, we may be able to tolerate some kind of modest level of certain endocrine disruptors. The problem is we don't test or try to determine what that concentration should be. So what we're trying to get across right now is this needs regulation and research more than a lot of panic amongst consumers right now. Fetal programming, you mentioned babies and

unborn babies being affected by some of these things. How are kids in the unborn affected by the social status and economic status of parents. That was surprising to me. I guess it shouldn't have been totally new, but it doesn't bode well for societies with lots of poverty or planets with lots of poverty when even unborn children alongside kids that are born are affected by the social status and economic status of their parents. That sounds like a problem that's not going to get solved in one generation or through a couple government policies, right? It means there's lasting damage to poverty. Yeah, this is one of the critical themes that I wanted to try to get across in the book, because especially in countries like ours with this heroic individualism,

there's this tendency that we can just tell anyone out there in our country to pull themselves up by their bootstraps, get a grip, and all opportunities are equal. And that is fundamentally flawed when you look at the data. So when we talk about things like contaminated water, water that might be contaminated, not just with endocrine disruptors, but heavy metals like lead, which have very demonstrable effects on cognitive abilities as well as a tendency towards aggression. We find a lot of these sorts of things in poor neighborhoods. So socioeconomic stress has long been associated with people having problems getting out of poverty. But we always go back to this idea. The more I read the data, the more I consider this fantasy, that anybody can pull themselves up out of poverty. I think it's certainly possible in rare instances. Okay, it's certainly been done. But for the vast majority of people, we have to respect truth

and understand that these individuals, some of them in impoverished areas who are not getting the proper nutrition, who are possibly ingesting toxins or heavy metals, and who are experiencing perhaps exposure to drugs and alcohol during pregnancy. These individuals are going to be very ill-equipped. They have been epigenetically altered, as you refer to it as fetal programming. This is not their choice. They did not choose to be exposed to these stressors while they were in the womb. So how can you possibly blame that child and just say,

this is all on you to grow up without any help or assistance or very minimal levels of it, I think the science is really making people reevaluate our idea of what socioeconomic stress does to individuals and how it really holds them back. And what epigenetics has done over the past decade or so has attached some real tangible data to that process. So if you look at the genes of someone who is born into poverty, they are epigenetically modified at genes that regulate stress and aggression. So we've already set this child up for a monumental uphill climb that I think we just take for granted in a privileged society. Yeah, it sounds political on its face, but also it really isn't if there's science behind this, right? If we're saying, hey, people who don't have the same resources

actually have children who are affected by their own lack of resources, and it's not just a matter of habits or behaviors from that person. It speaks to the inequality that you have in a society, but how to fix that is the question. We all know how equality of outcome ends up, but I don't want to turn this into a political show here. I'd love to speak more about the microbiome as well. What is this, and is this why my friend's homes smell? Yeah, it probably is, especially if they have pets, they have microbiomes too. So your microbiome refers to the collection of trillions of microbes that live on and inside of your body. And we knew, like, for instance, our intestines house trillions of bacteria, and they're

there probably to help us digest some foods, maybe keep nasty bacteria at bay through competition, but we didn't understand that they have far-reaching roles into personality and behavior as well. And that's what scientists are discovering now, that the microbiome seems to have additional roles that we never appreciated before. So what these microbes do in our gut, and there's hundreds of different species, they make all sorts of different biochemicals, and they have an impact on our body. And no one has the same microbiome. In fact, your microbiome can even change as you get older or become exposed to different environments. So this is a dynamic entity to a degree, and it shifts the biochemistry in your body, and that's going to alter perhaps your brain chemistry.

And this was demonstrated in a very famous experiment not long ago when scientists took what we call germ-free mice. These are mice that are born under sterile conditions, so they don't have a microbiome. They don't have any microbes in or on them. and they're kept in these sterile cages, which allows scientists to then transplant microbiomes into them to see what happens. So here's where it gets interesting. If you take a microbiome sample of intestinal bacteria from a depressed person and put it into a germ-free mouse, that mouse starts to exhibit symptoms of depression. It won't be interested in treats. It won't socialize with other mice. and if you drop it into a bucket of water, it won't even try to swim out like a normal mouse would.

So this was a huge discovery that links for the first time. Something about the human microbiome is linked to depression. And to me, that might reshape how we treat this disorder shortly down the road. Yeah, it seems crazy to me that the microbiome can weigh as much as our brain. And I know this because I read it in your book, but also because I had a colonoscopy. So when we clear out those pipes in preparation for something like that, we're literally shitting our brains out, it sounds like. Yeah, our second brain. Our second brain, yeah.

And dogs can track this, right? Not the pooping part, but dogs can track the microbiome. Now we're seeing things like dogs that can sniff for cancer. Is that kind of what's going on? Is that something different? This was another element that I did touch on in the book because there's been chatter about the microbiome being a unique fingerprint for people. It's almost like DNA. Like I said, you carry around a specific assortment of microbes, and scientists can not only identify what they are, but they can identify the relative quantities of them.

So the microbes sitting in my gut are definitely going to be different than the ones that are sitting in your gut. And if forensic scientists were able to extract samples at the site, or what they're showing now is that dogs can even smell some of these, they don't smell the microbes themselves, but they smell the by-prose. what these microbes are making, and they have an exquisite sense of smell, they can identify and link those scents from the site to a person who carries that microbiome. So that's where things get really compelling and really interesting. The gut has 8 million genes in it, you wrote. But is that kind of like saying the chicken I just ate has a ton of genes in it because there's DNA in the meat?

Or are you talking about something else? Well, if you eat a chicken, of course you're consuming DNA, eating those chicken cells. but your stomach's going to destroy all that. It's going to rip those molecules apart, limb from limb. Okay. So Jordan can live another day. But the microbes in your gut, even though they're reproducing and dying and turning over, those genes are actively producing things. Okay, they're actively making things. And it's been shown that what they make can get into the bloodstream and can go to the brain. And that's how they can possibly affect mood and behavior as well. So these biochemicals made by the bacteria are, dynamic and affecting our bodies in ways we're just beginning to understand. So we're more bacteria than human from the sound of it. The current estimates say there's slightly more bacterial cells than the cells that make up our own body. That's true. That's a gross way to start lunch. So hopefully people are not

eating while listening to this. It's a funny visual that there's so much going on down there, that there's actually more than in the rest of my body. You mentioned being a supertanky, Now, this is something that I've experienced. I'm also a supertaster. Tell us what this is, because I've just heard, oh, I have more taste buds than normal people, but what it results in is me hating a lot of things that other people love.

Yeah, and that actually was one of the first things I wanted to tackle when I got into writing this book and researching it, because like you, I was a very picky eater growing up, and it drove some of my family members crazy. One of the vegetables that I couldn't stand was broccoli, and I still can't stand it to this. day. And while I was growing up, most people seem to enjoy this vegetable. And what the hell is wrong

with these people? Can't they experience this awful taste that I feel? My brain thinks it's a poison. How can you stomach this? What the science has borne out is that there's supertasters among us, about one quarter of people, 25% or so are supertasters. And I actually got the genetic test to prove it. I don't know if it convinced my parents why I didn't eat my vegetables when I was young. But I have genetic proof that, yes, I have the gene mutation that creates this excess of bitter taste buds on my tongue that have a heightened reaction. So that is telling my brain, like, what you just put in your mouth is really bitter. It's probably poisonous.

You should spit it out. You're listening to the Jordan Harbinger show with our guest Bill Sullivan. We'll be right back. When it's time to scale your business, it's time for Shopify. Get everything you need to grow the way you want. Like all the way. Stack more sales with the best converting checkout on the planet. Track your cha-chings from every channel, right in one spot,

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you can check them out for yourself at jordanharbinger.com slash deals. Please do consider supporting those who support us. Now, back to Bill Sullivan. I'm not a picky eater when it comes to a lot of things, but stuff like kale is just horrible. You know, I eat it, I'll choke down the juice, but it tastes almost like a gasoline-type flavor. It's not exactly it, but it's really, really bad.

It literally does taste toxic. Like my brain is telling me don't eat this. It's bad for you even though everybody at the trendy vegan juice place is like, isn't it so good with some other things that you never put in your body? And it seems interesting that this is by design. If vegetables are good for me and eating less of that is bad because they're good for me, being a supertaster hurts me then, right? It's a double-edged sword, actually.

You're absolutely right that supertasters do tend to have a poorer diet. Usually later in life they have health outcomes that reflect that. So it's really good that you got your colonoscopy because that's one of the risk factors associated with being a supertaster is colon cancer and, you know, things like that, because they tend to eat more meats and things like that, less vegetables. But all supertasters should try to identify some vegetables that they can incorporate into their diet that they can stand or explore ways that they can cook food. Personally, I think kale is beyond help. That's just not going to work for us. There's nothing you can do to it. You know, deep fry it and chocolate sauce, as the famous Seinfeld episode said, I'm still not going to touch it. But there's plenty of things like potatoes, carrots, corn, spinach is okay with me. Yeah. I can stomach all of that. But here's where the advantage comes in.

And it's not an advantage that you and I can enjoy per se because it happens at a population level. What biology likes to do in order to ensure the survival of the species is create diversity amongst the population. This works very well with like immune systems or else the whole tribe could be wiped out by a single pathogen. but there's always going to be some small fraction that are immune to that pathogen, just because we have diverse immune systems. We have diverse taste buds, so the theory goes, to prevent people, a small tribe way back when in our evolutionary past might have moved into a new environment. There was new vegetation that we weren't sure about.

Some people start eating it. They don't taste any unpleasantness to it. But as supertasters would have put it in our mouth, tasted the bitterness, and said, I'm not going to, I'm not going to eat this. Let's say that plan ended up being poisonous. Okay, a lot of the other people might have gotten sick, maybe even died, but about 25% of us would have lived and we would have carried on the species. I know we pass on some food preferences in utero, and this is something that explains a phenomenon which I witnessed when traveling, which is that I see little kids in Vietnam or Thailand eating super spicy food that I can't

even touch. And I love spicy food, even though I'm a supertaster and we're not supposed to. I love spicy food, but I'll try something that I see like an eight or 10 year old eating and I can't even get near it. Like my eyes are watering. And I thought, how does this happen? Sure, when the kids are little, maybe they're fed that kind of food when they're young and so they're used to it. But according to what you've written here, women are passing on food preferences before the child is even born, which I suppose makes some sense, given how umbilical cords transport those things to children, but it seems like the gut biome and other cravings are also transmitted that way, which might explain some pregnancy cravings as well.

There could be a lot of different aspects to this. Taste preferences are actually very complex. Supertasters are one of the more easier ones to understand. A proclivity for spicy foods in very young age probably has something to do more with the culture. But you can certainly make a case, and I don't know if there's science to support this, but based on what we do know, I think it's reasonable to speculate that a child, while still in the womb, could be epigenetically programmed if the mother is consuming a lot of spicy foods, to dial down the thermoreceptors that respond to the capsaicin, the chemical that makes these things spicy, and therefore be a little more immune to that spice. That's one possibility.

I think I recall reading a recent study about the microbiome in our mouth. We have an oral microbiome, So just to extend the grossness, not only do we have intestines swarming with bacteria, they're in our mouth as well. And they process the food as we start to chew it and break it down. And they release enzymes that can perhaps neutralize some of the flavors in the food. So in some areas of the world, the oral microbiome may be influencing the taste experience. The other interesting thing about the in-utero experience, in addition to like epigenetic modifications that may take place, is that there's pretty compelling evidence that the embryo, the fetus, is experiencing some of the chemicals that the mother ingests through her diet. I recall an experiment, and I'm hoping I'm getting the details right, but pregnant women who were ingesting garlic, they sampled the amniotic fluid after they were ingesting garlic.

garlic, and it either smelled or even tasted like garlic, which was convincing evidence that these flavors are actually getting to the embryo. I don't know what you'd need to do, how much you'd need to pay me to sample someone's amniotic fluid. Is that even safe to do? I guess they have to test people for all kinds of diseases and things like that, but I don't know. I don't know what kind of check I would need to take a shot of that. Science is full of some pretty weird experiments, and it does raise the question, how did they loop people into doing this? The other famous experiment that comes to mind involves people sniffing T-shirts that have been worn by in-showered men for two weeks to rank them as to whether they thought the smell was

okay or repulsive. You've got to pay me a lot to do that one too. Yeah, although I will say doing an amniotic fluid tasting or doing a flight of amniotic fluid It's pretty gross. It's not what you normally set out to do on a Friday night. No, no, definitely not. There's a couple other gross experiments I'd love to talk about as well. How do we know that gut bacteria affects appearance and health? I know there's some mice experiments here, namely mice eating another's poo

and it changes their fitness and appearance. That to me is crazy. That really does show the microbiomes effect. So hear me out here. I'm not saying I want to try this, but has anyone tried feeding super? perfect people's poo to obese people to see if that works. It sounds horrible, still better than kale. I don't know about that. Let's see. What you're describing, scientists refer to as fecal transplantation, or in a less gross way, they call it microbial transplantation. Because it's not necessarily the poo,

per se, that is the critical ingredient here. It's the bacteria that resides within it. Right. There's an excellent medical indication for fecal transplantation. So real quick, some people suffer from a bacterial infection called Clostridium difficile. This is a horrible intestinal infection that produces massive diarrhea, and it's just an awful experience, and it's really untreatable through antibiotics. For decades, scientists were like stuck, but what fecal transplantation does takes intestinal bacteria from a healthy donor, and it's not like ingesting poo. Scientists process it, put it into capsules, okay, and then you just chug these capsules down.

And it basically gives you these new bacteria from the healthy donor, and it supplants the intestinal microbes that have gone into disarray in your own gut and allowed claustridium to thrive. So once you get those healthy bacteria back down into your gut, then the claustridium resolves. It's got a 95% cure rate, which is just amazing from a disease, which we were powerless to treat just 10 years ago. So fecal transplantation has some real potential in helping things, perhaps beyond claustridium infection.

This circles back to the interesting mouse experiments. These studies are not done in humans and we're certainly not encouraging people to biohack or do any of these things on their own. This science is in its infancy. We still have so much to learn and there are potential dangers associated with fecal transplantation. Some of the cool things done in mice where we go back to these germ-free mice that I told you about, They don't have any microbes in them. You take some of these germ-free mice, and you can take intestinal bacteria from identical twins who are discordant for obesity.

Remember, that means one of the identical twins is lean, one is obese. So it takes some of that intestinal bacteria from the lean twin, put it into this germ-free mouse. Nothing happens. It stays lean. It stays healthy. But if you take intestinal bacteria from the obese twin and put it into that germ-free, mouse, it starts to overeat and it becomes obese. That was just a mind-blowing finding and it was the first

to really connect the composition of the microbiome to metabolic parameters like obesity. And that has been borne out in some preliminary human experiments as well. If you take a look at the microbiome from obese patients who then undergo bariatric surgery and lose a lot of of weight as a result of that. Sample their microbiome after the surgery, it's completely different than what it looked like before the surgery. So this is telling us that there really is a microbial component to metabolic disorders like obesity. Bacteria trigger hunger to get what they want, not what our body needs? You wrote this in the book. What does this mean? Because that has kind of strong implications for, I don't want to get too philosophical about it, but if I think, oh, I'm really hungry and I

want this, it's not really me that wants it some of the time, right? My gut's signaling to my brain, you should eat that cheesecake. At some level that sort of pisses me off, right? Like, I think I'm in charge. Meanwhile, it's a bunch of bacterium in my lower intestine that are like, hey, man, we're going to manipulate this dumbass who's walking around with us in his gut to do whatever we want. And I'm falling for it every time. And you're not alone in doing so. We are kind of prisoners to a lot of things. And that was one of the themes that emerged in the book that I struggled with as I wrote it. It takes a lot of agency out of what we think we are and how much control we actually have. At the end of the day, and I can explain this later, I think that's good news at the end of the day.

But it's disquieting at first. There's no question. We seem to be prisoners to our genes. We're prisoners to our environment. We're prisoners to our fetal programming, which we had absolutely no say in. We carried around evolutionary ghosts from our past ancestors. So what's left? right? And now we learn that our microbes are controlling us as well. And you're absolutely right. There's some

interesting studies that have suggested that bacteria can secrete biomolecules and they go to our brain and influence the cravings for the type of food we want. And it doesn't take long to alter what we want. And that's why I think getting addicted to sweets, for example, happens so quickly. Once these sugar-loving bacteria populate the gut, they send out signals to our brain. telling us, hey, go get more sugar, and we abide by our bacterial overlords, and we do that. Now, if you shift your diet back to one that is low in sugar, those bacteria go away, and they get replaced by ones that don't crave sugar. So you get into this positive feedback loop where you're not craving sugar all the time, eating it in low or very moderate levels, and it's all

dictated by the bacteria species in our gut. You said that was good. Why is that? Because it seems like I should be in control. Maybe it's better if I'm not and my gut can tell me what it needs, even though sometimes what it needs is just really what some invasive bacteria wants, like more simple sugar. Right. Well, here's why I say that there's a silver lining to this cloud. We didn't know for the longest time why people were so drawn to sugar and high fats. I mean, yeah, of course they taste good, but these things in excess are doing dramatic harm to the body, but why do we keep eating them? And it's because we are compelled by very powerful forces

beyond our control, influencing our brain, perhaps at a subconscious level. Now that we know that bacteria play a role in that, we can fight back. We can maybe come up with formulations of prebiotics or probiotics to change the composition of microbes that inhabit our gut so that they produce chemicals that make us behave better. Scientists and industry are very intensively looking for probiotic formulations that may help people

either crave the right foods or replace a bad microbiome with a good one that will encourage better health outcomes. Yeah, I'm imagining the fad diet of the future, or maybe the actual real medical best practice of the future is going to your doctor and he's like, all right, bend over and they put in some sort of giant vitamin type thing up there that is bacteria that gets you to say, oh, I don't need that much sugar, but I sure would love a salad right now, but no dressing for me, right? And some nice clean protein and things like that. All the right cravings are in place, all the wrong ones, that bacteria could get starved or removed by whatever formulation that is. I can see there's going to be problems with that kind of thing, but it sounds

like there's a definite possibility that we could change our gut biome manually as a opposed to doing it by changing our diet first, which is really, really hard and sticking to it, and then over time having that gut biome grow itself, it almost seems like we could kickstart the process by having the right bacterium implanted. Yeah, you could. That could be the way that initiates a change to more positive behavior. And of course, you would have to keep up that positive behavior or else you'll go right back to square one with the unhealthy microbiome. Right. So it's not going to be like one treatment will keep. you for life, it is going to have to be some lifestyle changes, but at least getting the right

microbes in place, it'll really give you an advantage. It'll give you an edge to make those changes. And there's good studies that show, like you're suggesting, it doesn't necessarily have to be something that we shove up there. Could be something we shove down here. Prebiotics are basically foods that encourage the growth of a healthy microbiome, and they are mostly the fermented foods that are naturally healthy for you to eat, and they're going to encourage the growth of a healthy microbiome. So this is like kimchi? Yeah, that's one of the popular ones for sure. But we should add, perhaps a little disclaimer here that certainly not advocating that people go out and start chugging a whole bunch of probiotics. There's no definitive study that demonstrates them to show any great

effect in normal healthy adults just yet. There's so much more we have to understand. I think it's premature to go out there and start fiddling around with probiotics, but it's perfectly fine to start eating more prebiotic foods. Toxoplasmosis, you read about this, it seems like this is something we can get from cats. And this I found online because somebody sent me a video of like a mouse attacking a cat, and the mouse, of course, gets eaten. And it turns out that this is how this bacteria gets into the cat. It somehow gets into the mouse by the mouse getting exposed to cat feces or something.

like that, the mouse becomes fearless or even aggressive towards animals like cats. Cats think what the heck is wrong with this mouse, kill it, take a big bite out of it, suddenly it's in the cat's digestive system, rinse and repeat. Really cool sort of evolutionary strategy here. And then I found that it can get into humans and then that started to freak me out a little bit, of course, as do a lot of these things that we're talking about here because it causes all kinds of problems. And now I've got little kids around my cats. You know, what should I do about this? Should I be worried about this? Yeah, we should have a nice little chat about toxoplasma. This is a parasite I've been working on for over 20 years in my laboratory at Indiana University School of Medicine. Fascinating

parasite. It's a single-celled organism, so it's not a bacteria, but it's a parasite that can induce behavioral changes in its host. Some of the remarkable things about this parasite is that it gets into all sorts of different animals, which is pretty weird, because most parasites only shuffle through one or two different species, but toxoplasma can infect any animal, including humans, and it infected a lot of humans. We're talking billions of people carry this parasite around in their heads. We'll come back to that part, but let's talk about the cat and mouse thing that you mentioned, because that's the centerpiece of the parasite's life cycle. The host that it wants to get into the most is the cat, because the cat gut is the only place that we know of where

the parasite undergoes the sexual stage of its life cycle. For some reason, there's something romantic about a cat gut that the parasite really enjoys, gets turned on by it. It allows them to go into the sexual cycle, which means the cat's going to excrete these parasite eggs called oasis out into the environment for about one to two weeks during the course of the infection. And most cats, you probably won't be able to tell they're infected. It's a pretty stealthy infection, doesn't produce a lot of overt symptoms. So these, these, These parasite eggs get expelled into the litter box, into the sandbox, into your yard, into the water supply, and these oocysts are highly infectious.

You can accidentally ingest them, okay, or you can inhale them. That's one of the major routes of transmission. Any animal gets infected. So let's say a mouse comes across some of these oocysts as it's running around the grass, accidentally ingests those, and becomes infected with toxoplasma. The mouse won't get all that sick, okay, just like any other animal. But the parasite never leaves the body. It ends up going to sleep in the brain in the form of tissue cysts. Hundreds, maybe thousands of these tissue cysts all throughout the mouse brain, it causes behavioral changes.

So mice that are infected with this toxoplasma parasite, as you suggested when you looked at that video, are unafraid of cats, which is remarkable because that is one of their basic instincts. An uninfected mouse, if it gets a whiff of cat odor, it's going to scurry as fast as it can in the other direction. A toxoplasma-infected mouse will actually be drawn to that scent and become easy prey for the cat, which is a very, very clever trick that toxoplasma has evolved to get back into the cat, which is where it would prefer to be. So it's like creating a zombie mouse, not quite, because the mouse still has other faculty, but instead it's tricking the entire evolutionary or survival strategy, I should say, of the mouse

and short-circuiting it. And honestly, killing the mouse, right? Because if a mouse is chasing a cat and pissing it off, its lifespan dramatically decreases. So it's essentially just taking over the driver's seat that completely hijacks the brain of this mouse and ends up doing so for reproduction. So what happens when this parasite or this bacteria gets into humans?

Can it cause problems? Am I going to have neuro cysts in my brain? You know, what about my kids? You will have cysts in your brain. But what they do or don't do, that's still a debatable question. Because we can't really do those experiments on people like we can in mice. What we can do are like correlation studies. And we should say correlation is not causation, but we can look at historical records and serology.

We can take blood from a person and tell them if they have toxoplasma or not. So if these individuals do test positive for toxoplasma, we know that they have cysts in their brain. some of the interesting studies that have been done parallel what we see in infected mice. So infected humans do have a tendency to take more risk. They become more anxious. They also have rage disorder and they have a greater propensity to become schizophrenic. So there's a variety of neuropsychosis that have been, again, correlated with the presence of the parasite in the human body. It doesn't say that they cause these things.

And again, the science is still relatively new. So we got to take it with a little bit of a grain of salt. But some of the other interesting things that stem off of that is that there was a study done in primates, non-human primates, that had toxoplasma. And they were given pads of cat urine to smell. And the uninfected ones, I think it was actually bobcat, okay? The uninfected primates were afraid of the smell.

They would go away from the smell. But the infected ones were not, which implies that these infected primates would have been eaten by a bobcat or some other major predator of primates, just like the mouse is being eaten. So it's possible that the parasite is manipulating our brain in a similar fashion that makes us take more risks and become easier to prey. And that would have been very significant back in our evolutionary past. but how it bears out in today's technologically advanced culture, what scientists have shown is that people infected with toxoplasma tend to be more risky entrepreneurs. They tend to be involved in a car accident more often than someone who might not be infected. So do you see this generalized risk-taking

increase in people who are infected with the parasite? Can I test myself for the? Can I test my cats for this and can I test myself for this? I do believe you can test your cat for it. And, And you probably could ask a doctor to test you, but I'm not quite sure what the information, how it's going to be useful for you, because there's no cure for toxoplasma. If you have it, there's nothing you can do about it. That's what my lab is working on. It might just shed a little light into perhaps some facets of your personality if you agree with some of these correlation studies that have been done.

Oh, I'm a safe driver. I guess mostly I'm worried about my kid, right? It's like, if my cats have this, I don't necessarily, I don't know if I want them around my two-year-old and my newborn. Well, yeah, that's a good point. Toxoplasmine investigators are usually very quick to add that you don't have to panic about cat ownership. Just follow some very simple, common sense rules, such as cleaning the litter box promptly, perhaps using gloves while you do so. Now, there is a very real danger associated with pregnant women, and maybe you've experienced this in going to the doctor, but pregnant women are

usually advised to not change the kitty litter at all, because there's a chance that if she becomes infected for the first time with toxoplasma during the pregnancy, it can cross the placenta and either cause a miscarriage or catastrophic birth defects, blindness and cognitive defects in hydroencephalus, which is swelling of the brain. So there's a very real danger there, and most pregnant women are advised not to change the litter box, perhaps not to garden, don't play in same, sandboxes, perhaps, you know, with their other kids, because those are major vehicles of transmission. And like we said, toxoplasma gets into all animals, and these parasite cysts form in all bodily tissues, not just the brain. So if you don't cook your meat thoroughly, the parasite cysts can get

into you that way as well. This is the Jordan Harbinger show with our guest Bill Sullivan. We'll be right back. Now for the rest of my conversation with Bill Sullivan. I'm seeing now because I'm paranoid, which maybe means I don't have it. In contrast, infection is uncommon in pet cats that do little or no hunting and primarily or exclusively eat commercial cat foods. So there you go. Hopefully, we're safe. These are indoor cats.

You know, my wife knows not to change the cat litter. I don't know where she read that, but she's been using that as a good excuse for the last few years. So we're safe there. Well, she only needs to use it as an excuse while she's pregnant. I don't want her to get mad at me for saying that. But that's the truth. It's only a potential danger while she's pregnant. And if your cats don't go out and hunt, and if they're not fed of raw or undercooked meat, the chances of them acquiring toxoplasma is pretty nominal. Good to know. Good to know. This is a weird aside, but I'm glad we covered it. You mentioned in the book as well about how abuse and neglect can get into our genes as well. We talked about chemicals and exposure and poverty and things like that. But abuse and neglect is interesting because we know a lot of people that have, of course, have rough past. I mean, it, it happens. It's no fault of their own. You're born into a house or you're adopted into a house that has these kinds of things going on or you leave that house even when you're younger. It's not

just something you can quote unquote get over even if your life improves for decades later on, right? This is still somehow expressed in our genes. This was one of the most fascinating things I found while researching the material for pleased to meet me. In addition, I mean, you can conceive how physical things in the environment might be able to interact with our body. But what we're talking about now are psychological events. So this is really fascinating. And what we're referring to here are adverse childhood experiences, things like bullying or neglect. They can obviously cause psychological scars, but what epigenetics is showing us is that these adverse childhood events can also cause epigenetic scars on our DNA. So if you look at

children who have been exposed to these adverse events, they have epigenetic changes at key genes associated with our stress response. So what we specifically see in some studies is that these children have epigenetic changes at a gene that encodes for the glucocorticoid receptor. So this is a stress hormone that is released by the body. Everyone probably is familiar with cortisol. It's a common stress hormone that children who are suffering from abuse or neglect are secreting all the time. It's chronic. This glucocortico-corticoid receptor normally cleans up that hormone. So in most normal people, they have a quick burst of stress, cortisol is released, and this glucocortico-cordicor receptor kind of cleans it up. Okay, so that doesn't cause any bodily harm. This gene is epigenetically silenced

in these poor children, and that seems to be present for life, even if they get into better circumstances, this gene just seems to have been shut off permanently. And without that gene being regulated properly, these children, unfortunately, even if they get into a better environment, are still maladapted to respond to stress. And they tend to be more paranoid, they tend to be suicidal, and they tend to be overly aggressive. So it really did screw them not only at a psychological level, but at the level of the genes, that's what the science is bearing out. And that explains why that most of the children, not all, most of the children still struggle even after getting into a better environment. That shows the importance of therapy if you have a background that you think

maybe isn't still affecting you because you're, you just can't be sure if this is expressed, if it's going to crop up later on. You know, it seems like something you don't remember shouldn't affect you, but it's not really the case, right? That's right. And another corollary to that study is a lot of people ask, that's not true for all children. So is there something special about the ones that show resilience? And there is. At least one study that I read said that those children have a mutation in a gene that is encoding what's called brain-derived neurotropic factor, BDNF. And long story short, that gene is specifically designed to protect and shield the brain from damage. So, it's remarkable that even the resilience is not something psychological that we summon from within. It's a genetic mutation that makes you resilient. What about phobias? You mentioned that these can also be contagious. This is kind of crazy to me. So it does make sense, though, right? If somebody's got a fear of something and it's passed down to something else, their offspring,

namely, in that same environment, that fear could be healthy. Phobia, what do we define this as? Is this an irrational fear or just a fear? Yeah, there's all kinds of different phobias. And, and, you know, human fear response is astonishingly complex. And it was kind of something that I drew based on a study that I read about that showed that in mouse models, fear can be inherited. So it's worth explaining this a little bit because it's a fascinating experiment and really shocked a lot of scientists because it should not have happened. This result was very unexpected. So the setup is pretty simple. Mice normally love the smell of cherries, okay, just like people. They like the cherry scent, but not if scientists deliver a little shock to them while they're smelling the cherries.

Mice that get shocked while they're smelling cherries quickly develop a fear of the scent. They become unnaturally afraid of the cherry smell. Now, you take those mice and you mate them. They have children, they have offspring, that are born of. afraid of cherries, which is remarkable because they'd never been shocked. They never saw their parents get shocked. It's just this new phobia that appeared out of nowhere seemingly. Why do we think this happens? So the leading hypothesis is that this is epigenetically controlled, and there is some good science to back this up. And just to make it even more fascinating, those children that are born with this new phobia of cherries, their children also are still

with the smell of cherry. So this happens through multiple generations. The effect eventually goes away, so it kind of dilutes out down the road. But we see a multi-generational passing on of this new fear, which is, this is crazy, because that should not happen if you're a classic Darwinian evolutionist. You shouldn't be able to pass on a learned behavior. It would be like, I taught myself how to play the piano, so my kid should be born knowing how to play the piano. That's not how it works. But with some simpler responses, like a fear response, this does seem possible. So it turns out, and this is another thing that kind of blew my mind, I had no idea that sperm cells have odor receptors on them.

Whoa. Did you know that? No. Sperm can smell. They can smell things, you know, in a crude definition of the word. But we have to remember that any time we taste or smell something, we're actually responding to molecules. And when these molecules get into our body, they go to more than just the olfactory receptors in our nose and up in our brain. They somehow also make their way down to sperm.

It's thought that when these chemicals trigger that receptor, it produces an epigenetic change at the fear response genes. Now, exactly how that, no pun intended, but how the nuts and bolts of that actually happens, that's still a little bit of a black box. but it gives us a clue as to what's going on, because they harvested the sperm from these mice that were shocked, and they were epigenetically different than mice that were not exposed to this shocking while they smelled the cherries. So it seems like kids who grow up maybe in war zones

or high crime areas, these aren't phobias necessarily, but a lot of the world exists in these conditions. A friend of mine who I interviewed the other day, you know, he goes to war zones like Central African Republic and there's kids that just grow up around constant civil war. It seems like if they are to escape this or even if the country heals and becomes a functional developing or developed nation in the next few decades by some almost miracle at this point, their children and possibly also grandchildren are still going to have trauma from this. Yeah, and there's actually historical records that track that parallel what you said. If you look at the Dutch hunger famine of World War II, there's some historical records that were kept. This is when the Germans blockaded the Netherlands, and they couldn't get food.

There was a serious famine there for years. And the children who were born of those mothers who were starving at the time, very interestingly, grew up to have problems with obesity and diabetes. And be like, that's really kind of weird and unexpected. their mothers were starving at the time of pregnancy, and now they're struggling with obesity, and it's not just because the environment changed necessarily. What is thought to have happened is some kind of epigenetic change that occurred, this fetal programming of sorts, okay? And then when scientists examined these children, they have epigenetic changes at the

genes that control obesity and metabolism. It's hard to say definitively what's going on there, but there's some hint. that this kind of epigenetic inheritance might be able to occur in humans, but a lot more research needs to be done. Circling back to the socioeconomic factors, the war zones, and so on, that is a really sad situation, not only because of the present turmoil that exists, but I think if this epigenetic inheritance is true,

it might explain why we get stuck in these cycles of violence from generation to generation to generation. We need intervention in order to break that cycle. I'm not optimistic that it's going to happen on its own because we see now very tangible things happening at the biological level, and we're powerless to do anything about that until we get in and intervene.

It seems like soon we're going to know more about how parasites, chemicals, combine with the environment to affect our brains and maybe even cause criminal or contribute to the cause of criminal activity. I assume this is going to change laws and public policy and even medical treatment of people afflicted and ideally prevent some future crimes. It kind of sounds like minority report, right? And like, sir, we know you have this bacteria because of your urine test and now you're

87% more likely to assault someone later. So now you've got to take these antibiotics in order to kill the bacteria to prevent future potential crimes. Yeah. I know I'm sci-fying it up, but that's kind of crazy. I know. If I'm not mistaken, I think I referenced Minority Report in the book. Because there's some shadows of that when you look at these what are called genome-wide association studies or g-was. People might have heard of that term. But basically what it boils down to is you're comparing the genomes of criminals versus non-criminals and looking for differences and similarities. So there's been a gene that comes up time and time again in people who are very aggressive and been put away usually for very serious, violent crimes. And it's called M-A-O-A. Some people call

it the warrior gene, but scientists hate that name because genes don't encode for behaviors. They encode for proteins. And there are plenty of people who have this particular gene variant in the MAOA gene that are not violent and who would not harm a fly. But it's a really interesting correlation. And what this gene does, it makes some sense. It produces. It produces. a protein that regulates neurotransmitters in the brain. And when this protein is malformed because of this genetic mutation, you get a toxic buildup of certain neurochemicals in the brain that have been associated with violence and aggression. There's a plausible explanation for why this gene mutation keeps coming up again and again in criminals. But we can't use it yet as like a biomarker,

like in Minority Report, and screen people's genes and say, you've got this mutation. we're going to have to keep you under lock and key. We're not at that level yet because there are people with this gene and that mutation who don't show any aggression and violence. So it's a puzzle. What about bullying? It seems like that could affect our DNA as well,

and that's scary as a parent. You know, my kid's a little bit small for his age. Nothing's happening. He's in preschool. Everyone gets along, but, like, I went to school. I know how it can be. And I'm a little bit worried about how something like bullying

could affect epigenetics or express. itself and children. And we hear all the time about kids who are bullied really terribly and it damages them psychologically. I see it in my feedback Friday inbox and we read about it all the time. Bullying is a very sad situation and it's better today actually than when you and I were growing up. I think it's safe to say there weren't any like regulations or programs or workshops in place. It's still a problem and we need improvement. But what we are seeing in adverse childhood effects and bullying is included under that umbrella are epigenetic changes. If it's a chronic situation. I do think kids are generally pretty resilient and they grow out of a lot of these

things if they were relatively minor and short term, especially if they have people to talk to to get them through these situations. But chronic bullying, neglect or other adverse experiences, then what we might risk are epigenetic changes at these networks of genes that control our stress responses. And those children might grow up to be a little maladaptive in terms of hand certain stresses or engaging in healthy social interactions. We spoke earlier in the show about agency, and we've talked a little bit about public policy, and we haven't really explored this,

but I'm wondering if you've done any work or seen any research on how the brains of liberals and conservatives differ. And I don't want to pick one side over the other. It's a very non-political show decidedly as such, despite the one-star reviews that say I'm a conservative moron and also a leftist shill, usually not the same review. But I'm curious because I would imagine there have to be ways in which each side has either

different epigenetic expression or different brain structure of some kind, because it really does seem like we are from different planets a lot of the time. It does seem that way. And that's what inspired a lot of scientists to investigate some of the basic personality traits that exist between your average Democrat and your average Republican. I can discuss some of the findings that I found in my research for Please to Meet me. Let's talk about genes first. So people can do genetic comparisons between a group of Democrats and a group of Republicans.

And the one gene that popped up again and again was a gene called DRD4. And there's a variant of this gene that seems to be present more often in Democrats than Republicans. What does DRD4 do and how might it be related to the personalities that we normally see? in these two parties. D.R.D.4 encodes for a dopamine receptor, and this is a receptor that works in the brain and is linked to the reward response. And people with this particular genetic variation in that dopamine system tend to be more risk-takers. They tend to be more daredevils. They are open to newer experiences. And if you think about it, that on average describes a Democrat more often than a Republican, just being more progressive and open to new experiences. I think that's kind of what people think of

when they characterize a Democrat. But a Republican being more conservative, likes things the way they are, likes tradition, doesn't want to change things necessarily, and likes these traditional values. And they don't have this compulsion through this genetic mutation to seek out adventures or new experiences. So that's one example of a genetic difference between the two. not aware of any microbial differences between the two. It would perhaps be interesting to look at toxoplasma and see if there's an enrichment in one group or the other. I don't know if that study's been done. Has anyone tried feeding conservatives poop to liberals yet, or the other way around, for that matter? Because both sides have produced plenty of crap, so we won't run short

on material. I made that joke in my TED talk. That would be a really interesting experiment to do. I would love to see the outcome, and it would be amazing, right? So something that is along the lines of the daredevilry that I told you about, this was a study done in mice, of course, but you can make a mouse that is normally shy and timid. You can make that mouse brave by giving it bacteria from a brave mouse is pretty remarkable. So your speculation has some science behind it. you can fundamentally alter the personality, at least in mouse, by giving them different microbes. This conversation really has, and your book, of course, really has thrown me for a bit of a loop

in terms of human nature versus human nurture, I think you put it. It really does seem like there's a lot more to be said for environment and surroundings. And I think, like, a lot of us, we kind of knew this, but I never thought it would be at the genetic level. I just thought, okay, my personality is this way because I'm around these people. I never thought my DNA has actually been expressed differently because of things that have happened to my grandparents or my parents or me or things I don't even remember, things I've been eating, things I've maybe been smelling or gotten bit by, I don't know. That's really crazy. It does also seem, though, like there's a field surrounding this that is ripe for over-promising, under-delivering,

outright griftery, right? There's a lot of brain supplements and people that say, hey, if you attach these electrodes to you, it's going to change your DNA. And kind of the whole field of neutropics, maybe not every single product in the space, but a lot of these things just seem like kind of nonsense and possibly even harmful. Have you looked into these at all? Yeah, I did. There's a warning towards the back of the book that whenever we make these new discoveries or develop new technologies, flim-flam artists are going to rush in and try to make a quick buck. So you're seeing all sorts of people publishing books on how you might be able to epigenetically modify your genes through meditation or through changing your thought patterns or how you

might be able to change your microbiome through probiotics and so on. I think all that's fair game for speculation and it's tantalizing to talk about, but it's really premature to think that if you're going to pop a certain supplement or think a certain way, that you're going to alter your genes at an epigenetic level. There's just no strong evidence to support those sort of short-term quick fixes are going to amount to anything biologically significant. Bill, thank you so much. There's a lot to explore here. I'm looking forward to the next 10, 20 years of this science, and it really does sort of throw a lot of things on its head. So a good read and a good conversation. Really appreciate it. Oh, I appreciate the opportunity, Jordan. Thanks for providing

this forum for us to talk about some of this cool science. I've got some thoughts on this one, as per usual. But before I get into that, I wanted to give you a quick bite of a recent episode I did with Simon Sinek. He's been on the show a couple times. Simon is one of the most sought-after speakers and mentors in the corporate world, but he's no stuffed shirt. Well, here are some of his wisdom from the elite levels of public speaking, as well as his organizational skills that keep him at the top of the game. I have a vision of the world that does not yet exist.

I'm trying to build it. And whatever it takes for me to advance that vision, speaking, writing, teaching, whatever it is, I'll do it. I remember when cell phones were just starting to show up. You know, there was this great promise

that we could leave the office because of this device. And in reality, it backfired is we don't leave the office, the office comes with us. Right. We're always at the office, you know, because of the device.

One of the things that happens when we take the office with us is if we're not constantly engaging and checking in, we actually feel guilty that we're not. You know, you're walking to the subway, you're on the device. If you're off the subway, going to the office, you're on the device. We take the phone with us to the bathroom.

You hold it in and look for the phone. You know, there's something I'll be about that. That's so true. You know? When we're not connected, we actually feel guilty. And the reality is, is that ideas don't happen when we're connected. Ideas happen when our minds have an opportunity to wander. And this is why we have our great ideas in the shower, when we're driving, when we're out for a run,

when we're just going for a walk, because the brainstorming session actually isn't the time to solve the problem. The brainstorming session is the time to ask the question. Allowing ourselves these disengaged times is absolutely essential for innovation. It's absolutely essential for problem solving. It's absolutely essential for creativity to disengage with the device. The problem is, I don't know when it's going to happen. When I was writing Leaders Eat Last, I would have so many ideas in the shower, and I would forget

them as quickly as I had them, that I kept a dry erase marker in my bathroom and I wrote on the tiles. and so as soon as I got out of the shower while I was brushing my teeth, I'd write an idea on the tile. And so when I was standing there the next day, brushing my teeth, I'd be staring at my writing on the tile, and I'd sometimes have another idea. And so it looked like a beautiful mind. It was ridiculous.

All the tiles had these little chicken scratches all over. And I didn't want to raise any of them because I didn't know what ideas were going to be smart. But my point is, is like, if you figure out what works for you, do that. Keep a notebook by your bed. If you go for a run, take a notebook with you. I usually carry a notebook in the back of my pocket at all times

because I don't know when I'm going to have an idea. And like I said, I lose them as quickly as I have them. For more from Simon Sinek, including why it's important to have a worthy rival to stay sharp, check out episode 300 right here on the Jordan Harbinger Show. It really is incredible how humans are basically just biomechanical machines who are programmed in part by our DNA, by our environment, and even by one another. And the substances, of course, that we end up spraying on our rubbing on ourselves. So much more study is needed.

But the field of epigenetics is really going to open some needs. insights into what makes us human and why we need to treat ourselves and each other a whole lot better if we're going to make it as a species. I really learned a lot on this one. Big thanks to Bill Sullivan. All things Bill Sullivan will be linked in the show notes on the website at Jordan Harbinger. If you buy books from any of our guests, please use our links in the show notes because it does help support the show.

Transcripts are in the show notes. There's a video going up on our YouTube channel at Jordan Harbinger.com slash YouTube. My video's not there. Not sure what happened. Had to get a new camera. But Bill's video is there, and it's all right. You've seen enough of me already. I'm at Jordan Harbinger on both Twitter and Instagram,

or just hit me on LinkedIn if you want to connect over there. I'm teaching you how to connect with great people and manage relationships using the same software systems and tiny habits that I use. That's in our six-minute networking course. That course is free. It's all at Jordan Harbinger.com slash course. I'm teaching you how to dig the well before you get thirsty. And most of the guests you hear on the show,

subscribe to the course as well. So come join us. You'll be in smart company where you belong. This show is created in association with Podcast 1. My team is Jen Harbinger, Jace Sanderson, Robert Fogart, Millio Campo, Ian Baird, Josh Ballard, and Gabriel Mizrahi. Remember, we rise by lifting others. The fee for this show is that you share it with friends when you find something useful or

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