The digestive system is the group of organs that break down food in order to absorb its nutrients. The nutrients in food are used by the body as fuel to keep all the body systems working.
Digestive health with Ryan Goodwin, LifeVantage Chief Marketing Officer, and Brian Dixon, PhD, SVP of Research and Development.
Flip Your “Digestive” Switch: How Does Your Digestive System Work? Audio Transcript
Ryan Goodwin:
Hello, everyone. Welcome to Flip The Switch. I’m your host Ryan Goodwin, and today I’m with Dr. Brian Dixon again.
Brian Dixon:
Hey, everybody.
Ryan Goodwin:
And today we’re going to be talking about the digestive system. What it’s all about, why it’s important.
Brian Dixon:
Yeah. I don’t think a lot of people appreciate what’s going on in your digestive system. A lot of people don’t like to talk about it because usually you have to talk about poo to talk about the digestive system.
Ryan Goodwin:
Yeah. Let’s call it the most underappreciated system in the body, the digestive system. But around the house, at least, one of my favorite topics is poop.
Brian Dixon:
You do have, what, a three year old?
Ryan Goodwin:
And in my heart I’m a 12 year old boy. So Brian, why don’t you define the digestive system for us.
Brian Dixon:
Yeah. Really the digestive system encompasses everything that our bodies need to be able to break down the food that we eat so that we can extract the nutrients that we need out of that food. That’s the simple definition.
Ryan Goodwin:
I like to think about it starting basically right here, right? Or actually, it even starts before your mouth, right? Because there’s a visual component.
Brian Dixon:
Well, there’s more than even just a visual component. So yeah, it does. It actually starts quite a bit earlier than the food actually touching your mouth. It starts visually. Even when we see food, our body starts to prepare itself. So, it gets into the brain signal, the brain is sending signals through either hormones or direct nerve connections, basically signaling to the body through sight, through smell, that we’re about ready to eat a meal so the body better get ready to start absorbing all of these nutrients. And if you don’t really think that’s the case, if anybody out there has a dog, I’ve got about a 40 pound hound dog that we adopted from the pound and we make him sit before we feed him food. So as we’re putting food in his dish, we make him sit, he just starts drooling like it’s raining out there. We literally have to mop the floor. And that’s exactly the body starting to get ready, the fact that he knows he’s going to be fed, he can smell it, he can see it, his body is starting to prepare to actually eat that food.
Ryan Goodwin:
Yeah. So that drool is part of the digestive process. That’s how it starts to break it down.
Brian Dixon:
That’s exactly right. I mean, some fun facts for example, that dog’s drooling. But Ryan, you and I, every day we make between one to one and a half liters of saliva every single day. So you feel like you swallow a lot in a day, but think of your maybe two liter soda bottle. No one should be drinking soda, especially if we’re talking about digestive health later, but just to put that into kind of a visual representation, you swallow about half of a two liter bottle, or three quarters of a two liter bottle every single day in just saliva.
Ryan Goodwin:
That is nuts. That is absolutely nuts. So what we’re talking about here is our entire digestive track. And I heard someone else describe that as kind of like a donut, right? You’ve got the hole in the donut, and it starts here and it goes all the way through the end, and obviously there’s a lot of different things that’s going to happen as food passes through there so that we can ultimately get the things that we need in order to survive.
Brian Dixon::
No, that’s a really interesting comment. And you’re exactly right. We’re basically a tube that runs down the middle of us. A lot of us don’t appreciate that the cells that make up our digestive system are very similar, if not identical to the skin cells. So we have skin that protects us from the outside world, but this skin or barrier cells, epithelial cells they’re called, are acting like skin in our digestive system. So you want these nice tight connections with all of these cells throughout our entire digestive system so that our bodies can really regulate what’s actually being absorbed, and then also to keep the things out that it doesn’t want absorbed.
Ryan Goodwin:
Yeah. That’s what the name of the game is, right? And that’s got to be just a massive job, of all the things that we put in our mouths to figure out, okay, well what do we need to get through and what do we need to make sure doesn’t get through?
Brian Dixon:
It’s absolutely a miracle. I mean, just think of all the garbage we’re putting in our mouths. And not just garbage in the terms of junk food, but if food isn’t 100% sterile, and most of especially whole foods that we’re eating, fruits and vegetables, they’re not anywhere close to being sterile. So our bodies have to sort out all of this stuff, and it really, it’s messy work, no pun intended. But it’s just an amazing job that, especially the skin cells, these epithelial cells of our digestive system do to really regulate who comes in and who stays out.
Ryan Goodwin:
Yeah, it’s absolutely fascinating. If I remember right, the bulk of our immune system resources, if you will, in the body is basically around that digestive tract lining, especially in the gut making sure that the bad stuff is not getting too far into our systems.
Brian Dixon:
Yeah, that’s exactly right, because we’re putting literally dirty food inside of our mouths. And so yeah, it’s been estimated that about 70 to 80% of our immune cells actually are living inside of our digestive track, and specifically towards the bottom end of our digestive track.
Ryan Goodwin:
Yeah. Me personally, it took me a while to really care about my digestive track, because number one, I’m an ectomorph, meaning I’ve just always been super, super skinny, which means basically I’ve got two metabolisms and both of them are the size of a horse, especially when I was younger. So it didn’t matter what I ate. I could 8,000 calories in a day and I would still be that 8% body fat that I was when I was a kid. I was 6’2″ and 124 pounds. So, and it seemed like however little I ate or however much I ate, I couldn’t really affect how I looked. And I felt pretty good all the time being a young kid, so it took me a while to realize that I should care. I think it was my 20s when I started seeing my metabolism change ever so slightly. Not that it changed radically, but just enough for me to start caring more about at least the food options I was making. But I wasn’t also thinking about, well how do I make sure that my digestive system itself is actually working?
Brian Dixon:
Yeah, that’s a fair point. And that sounds like a little humble brag about you being an ectomorph. But that’s great, embrace that. Embrace that as long as you can.
Ryan Goodwin:
I don’t know about that. I hated being skinny. When I was a kid I found out that it’s okay to make fun of the skinny kid all day long, but I think it was probably just as hurtful. And that’s maybe even more hurtful because everyone knew that you shouldn’t be shaming somebody about their body when they’re bigger, especially to their faces, but for the skinny kid, it was okay to shame them all day long. And it was hard for me.
Brian Dixon:
Yeah, fair. That’s a fair point for sure. And I’m the exact opposite. My body, it will latch on to every single calorie that I put into it. So I’ve got to be really careful with what I eat.
Ryan Goodwin:
Yeah. Well, my body’s evolved so I’ve got to be far more careful, because I care less about how I look, I care way more about how I feel. And so now I’m way more careful about the food that I eat so that I can feel better. But I think one of the most important parts about that, about even the food choices that I’m making, is that it’s supporting a healthy digestive system. And when it does, I tend to feel better.
Brian Dixon:
Yeah. Well I think that’s the exact right approach. I mean it is the quote unquote healthy approach. It’s healthy because you’re making healthy food choices, but then that’s also the healthy approach psychologically to be approaching food. I mean, all of these concerns around body image, whether you’re too skinny or maybe carrying on a few extra pounds. Those healthy approaches to body image, whether it’s the food we eat, how we’re exercising, that’s really how we have to go about it. So that word health is just relates to every aspect as we’re talking about digesting here.
Ryan Goodwin:
It’s totally. So why don’t we spend a little bit of time going over the different parts of the digestive tract, the main parts.
Brian Dixon:
Yeah, absolutely. So we already kind of talked about how even just the act of seeing food, smelling food, maybe even hearing food being prepared really starts to prime our bodies to be able to absorb the nutrients that it needs from the food. If you’ve ever been to a restaurant, this is a little trick that restaurants have employed, they’re really leveraging the science of digestion in offering appetizers. It’s a very interesting, probably very primitive mechanism that they’re feeding on literally to take advantage of us so that we’ll order more food inside of a restaurant. So, have you ever been in a scenario where you’ve been in a restaurant, you order appetizers, they tend not to be very big, they’re not meant to be filling you eat the appetizers and you’re even more hungry than when you came in the restaurant in the first place? I don’t know if anyone’s maybe experienced this in their own kitchens. Maybe they’re preparing their food, getting ready to eat, or maybe in my case my wife’s in the kitchen cooking dinner. I’ll come through and start to graze a little bit on her wonderful food, and it just makes me more hungry. And I hate myself for doing it and I wish I wouldn’t have put that first food into my body because then I’m just dying for dinner to come along. But that’s an interesting phenomenon, because it probably stems back to our very early days when we weren’t always sure that we were going to get a meal, breakfast, lunch, and …
Brian Dixon:
That we were going to get a meal, you know, breakfast, lunch and dinner and just, even think of a hundred years ago, at the turn of the 19 hundreds. We weren’t guaranteed that we were going to have breakfast, lunch, and dinner every single day.
Ryan Goodwin:
Yeah.
Brian Dixon:
So our bodies have this mechanism built in that when we’re around food man, we try to eat just as much food as we can to try to bridge us through those periods of starvation. It’s no different than maybe a lion on the planes in Africa. When they get a kill, they just sit there and eat and eat and eat literally until they can’t move anymore. Go a few yards or meters away, lay in the grass and take a big nap while they’re digesting their food. So they’re trying to eat to make sure they can get to the next kill. And we have that exact same primitive mechanism that’s built into our brains.
Brian Dixon:
So be careful of that appetizer trick. Be careful of grazing too soon before dinner. It will encourage you to eat too much.
Ryan Goodwin:
Is that called premature grazing?
Brian Dixon:
Premature grazing.
Ryan Goodwin:
Sneaky. Those sneaky restauranteers.
Brian Dixon:
Science is clever. You got to give it to them. I appreciate anywhere I see science incorporated in everyday life. But you can also combat against it when you’re armed with knowledge and you know that’s exactly what’s going on.
Ryan Goodwin:
Yeah, absolutely. So what are the other major parts of the digestive tract?
Brian Dixon:
Yeah. So as we start to actually sit down for our meal, you know, I think most of us think that digestion really starts to begin in the mouth and you’d be absolutely right. So as we put food into our mouths, our bodies have already started secreting saliva. And saliva is rich in enzymes and it’s particularly rich in an enzyme called amylase. And amylase is designed to start to break down more complex carbohydrates so starches and other complex carbohydrates. This amylase enzyme that’s found in our saliva starts to begin to break down our food. But then we also have the mechanical act of chewing that’s also breaking those larger bits of food down into smaller pieces. And the more we can chew our food, we are one, mixing around that saliva through the food, helping with that digestive process. But then we’re also ultimately putting smaller pieces of food down into our lower digestive system where really the business of digestion really happens.
Ryan Goodwin:
I am a horrible masticator man. I don’t chew enough. I don’t chew enough. I’m just going too fast.
Brian Dixon:
Well, that’s one thing that’s been proposed. If you want to maybe reduce the number of calories that you’re eating in a meal, make yourself chew your food 10 times, 20 times, 50 times. I even hear people that will chew their food a hundred times before they swallow. So what you’re doing is lengthening the amount of time that you’re sitting down eating and you get more full before you’ve eaten a lot calories. So it’s one little trick people can do to maybe reduce the number of calories they’re eating every day.
Ryan Goodwin:
That’s interesting. And that’s also, I assume, going to make the food that you did eat more bioavailable, if you will, or just more efficient at getting the good stuff in.
Brian Dixon:
Yeah, you’re going to increase the efficiency of those enzymes working and yeah, it’s going to increase the efficiency of the absorption.
Ryan Goodwin:
I got to imagine that’s one step that is highly overlooked.
Brian Dixon:
For sure. Again, I think it’s primitive. Again, this will come back to lions on the plains of Africa. It’s literally a competition. It’s a competition between the rest of the pride to eat whatever that kill might be, but it’s not just within the family unit. It’s the vultures that are coming in. It’s the hyenas. There’s all these other animals that are racing in to eat food. So they’re literally not chewing. They’re just breaking off huge bits and just swallowing, just trying to get food down so they can get the calories they need to survive. And I think that’s why, especially my 10 year old boy, how I got to remind him 10 times every meal, chew your food, chew your food to your food. But it’s too hard to fault him because I do think it’s a very primitive instinct.
Ryan Goodwin:
Yeah, yeah. That primitive instinct is really strong with me. I’m like Jedi level non-chewer.
Brian Dixon:
That’s great, but you’re right. But the other thing, you know, chew your food more. It’s a great little tip to really manage the amount of calories you’re eating. But I think it makes you also be more mindful of the food that you’re eating, right? So if you’re really sitting down, you’re chewing your food, you’re really trying to experience how that food is tasting, how does it feel in your mouth. You know, it just makes you more mindful of what you’re eating and particularly how much you’re eating. It’s a great approach.
Ryan Goodwin:
So if you are spending more time thinking about chewing, right, is there any benefit there to the next step once it gets to the stomach? Both at the speed that you’re swallowing and then like is there something else that might be going on to get the stomach all primed?
Brian Dixon:
Yeah, absolutely. So once we’ve really kind of thoroughly chewed our food, right, it goes down the esophagus, a little tube that you can feel on the front of your throat there. And interesting to me, it takes about eight seconds for your food to go down that tube. So it’s not just a-
Ryan Goodwin:
Does it really?
Brian Dixon:
Yeah, it’s not just a little slip and slide where food’s just scooting right down there. You’ve probably seen pictures of it. It’s pretty bumpy, so it’s not really a smooth pipe. It’s also lined with muscles to help one, control the food going down, making sure it’s getting into the stomach and maybe not into the lungs. It also, it takes muscle contractions to squeeze that food down through the esophagus. So it takes on average about eight seconds for a swallow to actually get down into the stomach. So maybe something else to think about as you’re chewing your food.
Ryan Goodwin:
That’s crazy. I hadn’t thought about that.
Brian Dixon:
But yeah, then the food gets down to the bottom of the esophagus and it runs into an interesting muscle. It’s a muscle that’s really kind of the shape of a ring. They’re called sphincter muscles. So that muscle opens up and it allows that food to get into the stomach. And that’s sphincter muscle is really important. It’s really important to really lock the contents of your stomach in place so that it doesn’t come up. I mean, that’s why we can do headstands or handstands and we don’t have all this food just pouring back out of our mouth. So this muscle really controls what gets in. But then importantly, controlling what’s in not getting back out.
Brian Dixon:
So once that food gets through that first sphincter muscle, it gets in actually into the stomach. And just some interesting fun facts about the stomach, when it’s empty, it’s only about 75 milliliters in volume or about 2.5 ounces. But what else is very interesting is after we’ve eaten, it can expand by about 10 times. So about 750 milliliters or about 25 ounces in size. And so your stomach has a couple of different jobs. It’s one, allowing for very quick storage of food. So we tend to eat our food in a matter of minutes and it can store this big bolus of food and really kind of regulate the slower digestion that’s happening in the rest of our digestive system.
Brian Dixon:
But more than just kind of serving as this first storage compartment for the food that we’ve eaten, a lot of digestion really starts to begin inside of the stomach. I think a lot of people know that our stomach is just completely full of very harsh acid. In fact, hydrochloric acid, if you’re familiar, that means anything and you know not to get too grotesque, but you know, maybe you’ve had that occasional awkward burp and it tastes really sour and bitter. Well, that’s exactly the acid that’s kind of coming back up where it shouldn’t up into your mouth.
Brian Dixon:
So the stomach is holding the food. A lot of digestion is happening. That acid is incredibly important for a number of reasons. It starts to chemically break down, especially fats and proteins in our diet. But that hydrochloric acid down around a pH of two, it’s also serving as kind of a sterilization checkpoint. So not a lot of things that we eat can actually survive being dropped into a VAT of acid. So it kind of also serves as a first kind of cleaning facility for the rest of the digestive system.
Brian Dixon:
The stomach’s also lined with a whole bunch of muscle, so it’s not just a bag that’s sitting there, but it’s this really active moving bag. It goes through a process called [inaudible 00:00:18:49]. So it’s just kind of moving and massaging that food around that we’ve just ate. So it’s serving to mix the saliva further into the food that we’ve eaten, but also that acid to get more contact with those bits of food to start that initial digestive process.
Ryan Goodwin:
So it’s constantly kneading the dough down there.
Brian Dixon:
That’s a perfect way to put it, kneading the dough, kneading the food that we just ate. Well, and then I guess we’ll move kind of down into getting into the small intestine. So the small intestine would be the next big major step in our digestive process. But again, just like we’re controlling the food getting into our stomach with these sphincter muscles, there’s another sphincter muscle at the bottom that’s also controlling the release of that food into the small intestine. It’s slowly releasing food because the digestion process doesn’t actually happen that quick. I mean, it can take hours, many hours to even a couple of days for things to be fully digested in that small intestine. And the small intestine really is where the vast majority of our digestion, so breaking that food down further, but also the absorption of those nutrients that we ultimately want to liberate from our food occurs. Some fun facts about-
Brian Dixon:
From our food occurs. Some fun facts about the small intestine. It never made sense for me in biology or anatomy class, having to learn all these terms, but they call it the small intestine. They call it small because of its diameter, but it’s actually incredibly long in length. So listen to this, just you know, inside of your stomach, just below your stomach, kind of right around your belly button, you’ve got your small intestine that’s just wound up in this massive coil. And that coil’s around 22 feet long or seven meters long, just wound back on itself. And really what we’re trying to do is maximize the surface area of our intestinal absorption area to maximize the absorption of nutrients. So more than just being incredibly long in length, if you were to pull out somebody’s small intestine and hold it out and actually look through it, it wouldn’t be, again, just a smooth tube that you’re looking through.
Brian Dixon:
It actually looks like a big, wavy surface. So it’s on a microscopic level. We have all of these different wavy structures that go down our small intestine. And the whole reason we have these wavy structures is to increase the surface area, so maybe you could think of it as the coastline of Ireland or the coastline of New Zealand, or maybe if Catalina Island off the California coast. So you just have all these inlets and outlets, inlets, outlets that just really increased the surface area. Again, to maximize the surface area where we can absorb as many nutrients as possible, but more than that on the cells and our small intestines, there’s little hairs as well that kind of flutter around out there. That one helps move the food around, but it’s also aiding in the digestive process, so trying to maximize the content of the contact time of the food with the walls of our small intestines.
Brian Dixon:
So food gets moving along there. This is where we start to see some of the first digestive or healthy bacteria, probiotics, you’ve probably heard them called. We can start to find the first probiotics down in our small intestine. There’s not a ton of them there. Most of them live in the large intestine actually, but these probiotics or healthy bacteria are actually incredibly important to help us aid in the digestive process. They’re actually excreting enzymes that are helping us break down, particularly fats and proteins. So things like lipases and proteases. So they’re further helping us help ourselves by helping us digest our food.
Brian Dixon:
So as we get down through that 22 feet or seven meters of small intestine, we basically have done all of the absorption that we need, all the digestion, and really we’ve given our bodies the opportunity to absorb all of the nutrients that it needs.
Ryan Goodwin:
Yeah, it sounds like they misnamed the small intestine, first of all. Why wouldn’t they just call it the long intestine?
Brian Dixon:
Well, coming from a scientist who has spent a lot of time in science school, scientists don’t make anything easy. They’ve got to make everything as hard as possible for sure.
Ryan Goodwin:
When I was a kid, we called that the Ninja way. A Ninja never takes the easy way or he always takes a hard way.
Brian Dixon:
Absolutely.
Ryan Goodwin:
So scientists are ninjas or that’s what you’re telling me.
Brian Dixon:
That makes me feel way better.
Ryan Goodwin:
Yep. Scientists are ninjas. So just one quick question though. Is there any microbiome in the stomach then or at all? Or is that all killed by the acids and it really starts a little bit in the small intestine and then mostly in the large intestine?
Brian Dixon:
There might be exceptions of some probiotics that might be living in the stomach, but the general consensus is that even if there are these healthy bacteria living in our stomach, they’re probably not playing a massive role. And especially our digestive process. It would also, you know, it’s still to be determined really, it’s really hard to culture bacteria that would be living in that type of environment.
Brian Dixon:
But the general consensus is that if there is these healthy probiotics in your stomach they’re there at a really low concentration and probably not having a huge impact on especially digestion.
Ryan Goodwin:
Sounds like bacteria ghosts stuck in between worlds.
Brian Dixon:
Yeah. And again, it’s that harsh environment. We want the stomach to do all that sterilization.
Ryan Goodwin:
Yeah, yeah, yeah. So, so most of the absorption of all the nutrients is happening in the small intestine. Is there any absorption in the large intestine? There is a little bit of additional absorption that happens in the large intestine. So as we get down to the bottom of the small intestine, we move into this structure called the large intestine. A lot of people also refer to it as the colon. You can really use them interchangeably, but the colon’s job-
Brian Dixon:
Or the short intestine.
Ryan Goodwin:
Or the short intestine. Yeah, the large short intestine.
Ryan Goodwin:
But yeah, the job though mostly of the large intestine is to really start to package up the food that we’ve ate and really the waste products that we couldn’t absorb. So all the undigested food, you know, fiber is something that we have a hard time, that insoluble fiber is something we have a hard time digesting. So a lot of fiber will start to back up there. But really for the most part, it’s the large intestine’s job to start to package up this undigested food, the fiber, even water makes it through the process, package it up and get it ready to get out of the body.
Ryan Goodwin:
But that said, a lot of the microbiome that’s happening there, those healthy bacteria and other organisms living in our large intestine, and by the way, where the largest quantity of these healthy microbes are living, they are still helping us digest some food and we do have some absorption that’s going on. More of those proteases or enzymes that degrade proteins are excreted. More of these lipases or enzymes that help us digest fat are also excreted. So a little bit is happening there, but by far the vast majority of absorption’s happening in the small intestine.
Brian Dixon:
So would you say that’s like a 95% type of the digestion is actually happening or the nutrients are coming in through the small intestine and then another like 5% in the …
Ryan Goodwin:
Yeah, you’ll have to forgive me. I don’t, I don’t know the exact numbers off the top of my head, but if I had to guess, I’d probably put it maybe 90, 10 or 95, five happening in the small and large intestine, respectively.
Brian Dixon:
So we’re seeing and hearing more and more about gut health, and it may seem obvious, but why is digestive or gut health so important to us?
Brian Dixon:
Well, maybe the best way to think about quote unquote gut health is, let’s just use the skin as an analogy. So like I said, the skin cells are very similar to the cells that are lining our entire digestive system. And so yeah, we have to think about the health of our, of our digestive cells or those epithelial cells as well. You know, we want those cells to form incredibly tight junctions. I mean, think if you were to put your hand into maybe a bucket of mud or something, you wouldn’t want things being absorbed through there that you didn’t want. So the first function of those epithelial cells in our digestive track is to keep that outside world out. And a lot of the things that we want absorbed out of our food are actually very deliberately and actively transported across those cell membranes and then get pushed through ultimately and into our bloodstream.
Brian Dixon:
So we want nice, tight junctions where our bodies can regulate, right? Those cells can regulate exactly what’s coming across them, what’s making it into our system, and then ultimately into the bloodstream and circulated everywhere else. So you have to think, just like you think about the health of your skin cells. I think you also need to think about the health of these epithelial cells or these cells lining the digestive tract. And it’s really not rocket science. A lot of the things we talk about for healthy hearts, healthy brains, healthy skin, are exactly the same things we should be considering when we’re talking about healthy digestive cells. Because the problem can arise where if you don’t have healthy cells, maybe they don’t have these really tight junctions, just like if you had a cut on your hand, you’re going to start to let things into, especially your bloodstream that you don’t want and there can be some pretty harsh consequences as a result.
Brian Dixon:
But again, analogous to skincare, it’s not just the healthy nutrients that we want to be putting into our body, but what’s actually physically touching the skin. So maybe we want healthy skin care for our skin cells, but we also want to think about the healthy diet that we’re eating because there’s direct contact with that food and those cells. So we want to make sure we’re eating nutrient rich foods so we can directly nourish those cells. But even just the simple act of eating food that’s high in fiber, there’s literally a scrubbing effect of this fiber that’s happening against these epithelial cells. So as these fibers that we can’t digest are moving through there, you can almost think of them as little brushes moving down the digestive system and kind of scrubbing and cleaning the inside of our digestive tract as we’re digesting our food.
Brian Dixon:
So being really cognizant of what we’re eating, both from a nutritional point of view, but also from a fiber point of view, is also going to have a direct effect on the health of those digestive cells.
Ryan Goodwin:
Totally, totally. And something that I found out is that the gut brain index that some people call it is vastly important. And before I understood that the things that I ate could really affect how I felt and how my brain performed today, it didn’t occur to me that they were connected at all. But over time it became really apparent to me that the daily decisions of what I put on my plate had the biggest impact-
Ryan Goodwin:
Daily decisions of what I put on my plate had the biggest impact on how my brain was going to perform today and tomorrow than anything else that I could possibly do. That gut-brain index I think is one of the most fascinating topics on the planet right now.
Brian Dixon:
At first it was proposed, I’ll just… Forgive me for being rude, but there was some kooky people that were just saying, “Oh, the gut and the brain are talking,” but now there’s definitely really hard scientific evidence that… Quite frankly, that your gut is your second brain. It’s quite often referred to as your second brain.
Ryan Goodwin:
Second brain.
Brian Dixon:
There’s different words for it. The gut-brain axis is another word that I’ve heard, but literally, your gut, believe it or not, is actually communicating with your brain and your brain is communicating with your gut, and this is happening in a number of ways. It’s happening with direct connections with nerves, so you have nerves that run down and are directly linked to your digestive system. It’s also happening with hormonal signals. So your lower digestive system is actually excreting hormones, for example, telling you that you’re full.
Brian Dixon:
When you get hungry or you see food, you get hormone releases that get down and start to prepare your digestive tract to absorb these foods. But where it gets really interesting in this gut-brain axis is these molecules that are made, not just from the food that we’ve eaten, that digestive process, but it turns out a lot of those healthy bacteria that are living, especially at the very bottom of our digestive system. And again, if you think about that, they’re really trying to just clean up the scraps that we can’t absorb. It’s, again, a beautiful system, this mutualistic relationship that’s going on. So they’re really cleaning up our scraps that we can’t eat. And in the process of them metabolizing the food that we can’t digest, they actually make a number of very healthy compounds… Metabolites as a result of their metabolism that ultimately end up getting into our bloodstream. They’re going into circulation and so they’re affecting literally every organ in our body. And then there’s some very direct evidence that those molecules are acting like signaling molecules and having effects on brain function.
Ryan Goodwin:
Right, and if I understand properly, a lot of the hormones… People call them feel good hormones, but things that are obviously important for brain function… The vast majority is actually coming from the gut.
Brian Dixon:
Yeah, that’s absolutely very true. So things like serotonin, dopamine. They can also be produced by these healthy bacteria.
Ryan Goodwin:
Yeah. So over the next couple of weeks, we’re going to get more detailed on both the microbiome, prebiotics, and probiotics. But if there was one thing you wanted our listeners to both understand and start doing in order to optimize their healthy digestive system, what do you think that would be?
Brian Dixon:
Well, you got to choose healthy foods… I mean, I wish there was something sexier to say. I wish there was a quick fix or a magic bullet, but dang it, it just… Comes back to what our grandmas were telling us. Eat fruits and vegetables, eat fruits and vegetables. It’s so important because they’re nutrient dense, so you’re going to give your cells all the essential nutrients that they need, but they’re also especially rich in fiber, so you literally cannot eat too much fiber. The more fiber you consume, the better the health benefit. So choose foods that are tough to chew… They’re natural, they’re healthy, they’re hopefully full of bright colors. So eat healthy foods. If you want to supplement your diet, there are fiber supplements that are out there, so insoluble fiber, soluble fibers. And then another thing we can do in addition to just eating right, making sure we’re getting plenty of fiber is… think about those healthy bacteria that are living in your stomach.
Brian Dixon:
I know we’re going to be talking about this in future episodes, but quite frankly, your microbiome and those bacteria that are living in our digestive system are very reactive to the food that we eat. So they’re literally adapting and changing to the different diets. So if we’re meat eaters, we’re going to have a completely different population of these healthy bacteria living in our lower digestive system versus if we were a vegetarian, a completely different set of bugs, if you will, living inside of our digestive system. So eating right, one, is going to encourage the healthy bacteria that we want there that are going to make these healthy compounds that have effects literally throughout our body. But you can also tip the balance in your favor. And of course there’s a number of probiotic supplements that are on the market that are trying to help facilitate the growth of these healthy bacteria.
Ryan Goodwin:
Yeah, totally. Well, that’s solid advice and advice I definitely try to live by. What I’ve also found is that the first little bit was a little bit hard as I gave up foods that weren’t as healthy for me, but I really enjoyed… But over time as I purposely looked to make better decisions of food that went on my plate, I found that I started craving those things more and more and more. So it’s less likely that I crave that pizza that I was craving a few years ago and more likely that in a couple of hours I’m going to start craving a big plate of vegetables.
Brian Dixon:
That’s funny. That’s an interesting point. I was going to say the same thing. You can actually train your cravings. If you keep feeding the cravings with… Let’s say maybe you’re craving potato chips or chocolate. I mean if you’re just craving these things and you keep feeding it, you get this reinforcement that happens and it’s happening by hitting the exact sensor mechanisms in our brain that cigarettes, alcohol, drugs are hitting. So you’re really reinforcing that whole craving cycle. But you can break that chain and you can teach yourself to ultimately crave healthy foods. And I think it’s maybe a little bit different biochemistry that’s happening in the brain, but as your body starts to feel better and better and better, you find yourself reaching for those foods more often. And maybe another good tip for the listeners… I like to break my choices down into a binary decision. So this or that. And if you’re choosing the healthier option of those two options, more often than not, you’re going to start to drive yourself to choosing those healthier options.
Ryan Goodwin:
Yep. I couldn’t agree more. Well, thanks again for being on this episode and to the listeners, I hope you enjoyed this episode. We’re going to be talking more about the microbiome, prebiotics, and probiotics, so be looking for our next episode of Flip the Switch.
The views expressed in this podcast are those of the authors and do not necessarily reflect the official policy or position of LifeVantage or any other agency, organization, employer or company.
