Auto-transcribed and lightly edited for readability; speaker labels added by LIV3. Timestamps follow the player above. The views expressed are the speakers' own. Individual experiences described in the conversation are anecdotal, are not typical results, and have not been evaluated by the FDA.

00:24 Welcome and introduction

00:24Casey:Hello, and welcome to another episode of Boundless Body Radio. I'm your host, Casey Ruff, and today we have another amazing guest introduced to you now. Chris Mearns is the founder of LIV3 Health and the creator of the Fructose Model, a systems-based approach focused on how fructose metabolism may influence cellular energetics and contribute to chronic metabolic dysfunction. He is a primary author involved in the development of scientific literature advancing a broader model of metabolic health. His work integrates findings across biochemistry, physiology, and clinical research, with particular attention to fructose kinase activity, uric acid signaling, mitochondrial function, and cellular energy dynamics. This work aims to unify established concepts such as metabolic syndrome, mitochondrial dysfunction, inflammation, and neurodegeneration within a common energetic framework centered on cellular energy availability and recovery capacity. It also explores how this perspective may help reconcile existing models of metabolism while connecting survival pathways to the progression of chronic disease. Chris is known for bridging the gap between scientific research and real-world application. Through podcast appearances and on his YouTube channel, which is at the Fructose Model, he translates complex metabolic science into clear, usable insights for both general audiences and health professionals. Chris Mearns, what an absolute honor it is to welcome you to Boundless Body Radio.

01:43Chris:Likewise. Thank you so much for having me, Casey. I'm excited about this.

01:47Casey:It's an honor to host you. You're one of our friends from across the border. It's been a tough year for hockey around Vancouver and in Canada in general after the Olympics, an insane game in the men's and the women's and the Paralympic. And we know the Canucks are having a tough time right now. Sorry about that.

02:03Chris:Oh, thanks so much. It's been fun, though. We've had FIFA here. It's been a really busy, busy few months. So it's been an exciting city, actually.

02:15Casey:The World Cup looked amazing. Were you able to make it anywhere near the game?

02:20Chris:Not too far from us was kind of a watch party going on. And yeah, it was wild. It was relentless. There was so much activity going on and so much multicultural energy. It was really fun. It was a cool space, it looked amazing, and I was so glad that everybody who came here seemed to have a really good time. You got to see videos of fans from different countries partying together and learning their dances, the Norway guys doing the row and all that stuff. It was a super fun tournament.

02:52Casey:It's cool. It was right in your backyard.

02:53Chris:Yeah, it was really awesome.

02:57Casey:That's amazing. Question number one, my friend, we're going to get into your personal story, but before we do, we're going right for it.

03:00 Is fruit healthy?

03:00Casey:Is fruit healthy, my friend?

03:00Chris:That has got so much nuance to it, and I think that's the tricky part. I would say, of course, yes, it is. I'm not going to invalidate anything. I honestly think that fructose itself is not unhealthy, I just think context is super important. But that's a great question to throw at me to start, because yes, just like with anything, I have a feeling that too much of a good thing can turn into a bad thing. And fruit is great in most contexts. We've got blackberries ripe right outside our door right now, and every day we're going and getting dyed fingers and pricking ourselves, just harvesting them all because they're amazing. So I don't want to take away from that whatsoever, but too much of it can actually start pulling on a lever that I'm sure we're going to get into.

03:56Casey:We're going to get into that, that was a massive question, I just wanted to see how you reacted. We've got a lot of people listening who are carnivore diet enthusiasts, ketogenic diet enthusiasts, and they will say that because of the context, these things are unhealthy. I'm with you, I say the same. I've been on the carnivore diet for seven years, I've been coaching people on carnivore for years and years, and I do not tell people that fruit is inherently unhealthy, but there is a context there, and I think you do such a great job of explaining that, we'll definitely get into all of that. But before we get into the meat of that, will you describe what it was like growing up in Vancouver, what your professional career interests were, and how you ended up getting into fructose, because this doesn't seem like something that you've always been fascinated by.

04:38 From Vancouver tech career to the fructose model

04:38Chris:No, that's totally true. I grew up as a kid in the eighties, a typical childhood I would say, I had absolutely no concept of what was healthy or what wasn't. My mom was diving into the Best of Bridge cookbook, and I felt like it wasn't until I got married that I discovered what cheese really was. I got cheddar, that's pretty cool, but I think the first time I ate Havarti, it was like, whoa, what's going on here. So it was fun, just kind of the regular kid of the eighties situation. Eventually my career led me toward tech, my dad kind of told me, okay, this is where the world is going, you should be part of this space, and I was like, yeah, but I like art. So many years later, I found myself in this space where I was very involved with user experience, I kind of understood the tech side, but I was also trying to apply it to people's general experience in using technology. Eventually I found myself doing user research for VR headsets, kind of a weird twist on that. But it started tugging on this thing where I wanted to understand bigger problems, take a look at big challenges and try to identify how these matter to people. That was interesting when it comes to VR headsets, do they have a place, are they interesting, are they valuable, I don't think we still entirely solve that. But along that road I ended up becoming a parent, and that whole idea of having these big puzzles I wanted to figure out started pulling on me. It was like, okay, maybe health matters too, it wasn't something I looked at before. Now I have a little girl, and I was like, okay, I need to be healthy, and I'm already in my mid-thirties, I need to start thinking about that, because doing the math, I'm going to be a little older by the time she grows up, and I want to make sure I'm healthy for her. So I started reading different books and ended up diving into different metabolic literature, and it was like, okay, this is really interesting. Just like so many other people in the space right now, we're digging into stuff that probably we weren't really interested in many years ago. But the cool part is there's so much amazing research now, and it's still very siloed in its own spaces. With so many tools these days, we can start integrating them a lot better and start to see how they relate to each other, why metabolic dysfunctions cluster, why cognitive dysfunction and liver dysfunction travel together, or other things like that. When we start uncovering the biochemistry there, we start to see that there are a lot of things happening at the same time, and it's starting to reveal a bigger picture. So that's kind of where my background is.

07:54Casey:Fascinating. If you're in this world for long enough and you say the F word, fructose, there's kind of one name that really comes to mind, one researcher who's done a ton of work in this field. He must have been incredibly influential to you.

08:04 Dr. Richard Johnson and Nature Wants Us to Be Fat

08:04Chris:I'm sure you're talking about Dr. Richard Johnson, of course, and it was his book that really got me into this rabbit hole. That was about five years ago or so, I read Nature Wants Us to Be Fat, and it just blew my mind. It was like, okay, we're looking at sugar in a different way here, not just in its biochemistry, but in its role as activating a survival program. And do we want that, do we need that today? Why would we be running a program that tells our body to conserve when we're surrounded by abundance all the time in the modern world? So that book was definitely the beginning of my rabbit hole, clear as day. But I also didn't find it completely actionable. It was like, okay, I need to cut sugar, maybe raise my vitamin C, and I kind of sat on that for like two years where I wasn't really sure what to do besides having a really restricted diet. I started experimenting with keto diets, carnivore for a while, cutting alcohol, and it started to say that all of these different ideas we've had of diet camps and everything else all kind of map back to this whole system. And that's great, but it's also not actionable. So it was a couple years later, when I started digging deeper, that I started to realize there are perhaps ways we can make this more actionable in the short term, just by digging deeper into the literature. But I don't want to jump too far ahead, so maybe we should talk about that later.

09:41Casey:Yeah, let's do it. I found this book fascinating, I remember exactly where I was listening to it when he was explaining that fructose drives aggressive behavior in animals, for example, and I was like, I've never considered that, that's incredible. And the thing I like about it, as much as I love the low-carb space, the keto space, the insulin model, there seems to be little holes here and there and little questions of things we haven't fully understood. And what I appreciate about his work, and what I really appreciate about your work, because it is more actionable, is that it's very unifying. We mentioned that in the introduction, it kind of plugs those holes. And I've found that the more unifying something is, the more true it tends to be over time, the more we can go toward that direction and have much clearer explanations. That's what your work in particular reminds me of, we can take ideas of calories and insulin and all this stuff, but it's more complete the way that you explain it.

10:41Chris:I love that you say that, because I don't want to take credit for it, but I think it's absolutely fascinating. You've got, for example, the caloric model, we know that's a thing, you eat more calories, you're going to put them somewhere. But is a calorie a calorie everywhere? Is that ignoring the fact that fructose is seemingly not as much of a calorie as it is a signal? Because if it's telling your body to conserve those calories, that's a big deal, that's like adding an extra layer to the calorie model, where calories are super important, but now you're throwing an extra weight on every one of those calories that you're eating. That seems to be a big deal. Or insulin resistance, I know the insulin model is largely validated, we've got insulin resistance in so many different tissues, in so many preclinical states of so many metabolic dysfunctions. And yet I have to ask, is that the problem, or is that a response to something else, an adaptation? When you look at it from this lens, if fructose is causing a bottleneck in your cell, reducing the capacity of converting fuel into energy, then it almost starts to make insulin resistance look like an adaptation. If the cell is obviously starving, it wants more energy, but if it can't handle it and we're constantly trying to cram more energy into that little bottleneck cell, then you'd be adding substrate into a system that would basically become toxic, because you've got all this extra that you just can't handle, and it would eventually kill that entire system. So maybe insulin resistance is the pushback, saying if you were to actually push too much of that into me, it's going to be maladaptive. That insulin resistance is trying to protect you starts to make a whole lot more sense too, and it reveals that energy handling might be at the root, where our mitochondria, inflammation inside the cell, all of those things might be one layer deeper, informing all these other ideas.

13:10Casey:I love that, so well explained. I think it was Gary Taubes who explained, if you want to get rich, you need to earn more money than you spend. That's not wrong, but it doesn't explain hardly anything, like how do I get money anyway. Tell us what fructose is.

13:28 What fructose is: traditional and modern sources

13:28Casey:What are the traditional sources of fructose, and what are some of the more modern sources of fructose?

13:41Chris:Love that question. Okay, breaking it down: fructose is a simple sugar, and we usually encounter it in sucrose, table sugar. Sucrose is 50% glucose, 50% fructose. High fructose corn syrup just bumps that up to about 55% fructose, changes the form to a more bioavailable liquid form, but it's still roughly that fifty-fifty split. So that's where we encounter most of our fructose. Really, the question is, what do they do? Well, we know glucose is fuel, and our brain would quickly have trouble if we didn't have enough glucose, with the exception of ketones. But basically, glucose is the body's preferred fuel, and that's one half of it. The other half is seemingly sending a message of what to do with that fuel. Fructose is basically saying, down-regulate your fuel usage so that fuel can be conserved as much as possible, because we have this little bit of abundance, and sending that message along with it could actually be useful. I've got all this sugar available, that's a pretty cool opportunity for me as an animal, and I should probably hold onto that as much as possible instead of just burning it all immediately. So even though those are seemingly contradictory messages, fuel and fuel conservation, it actually kind of makes sense. That's where we get most of our fructose from, sugar these days. But most of us will also appreciate that it's very abundant in fruit, and that might be where the story gets more complicated, because most people appreciate fruit as healthy.

15:30 How fruit ripens: from fat-burning to conservation signal

15:30Chris:If you want to talk about fruit for a minute, the complexity of fruit really tells an interesting story. When fruit is unripe, it's dull, it's hard, it's fibrous, it's sour, it's not bright in color, it doesn't smell like anything interesting, and that's protective. But the process of ripening, and this is different from vegetables, which are basically immediately available from the start, fruit actually goes through this very interesting process where it starts with fat-burning properties and basically replaces them all with fructose, which then sends that ripened conservation signal. That's useful for the plant, because the plant is basically trying to encourage us as an animal to eat the fruit, poop out the seeds, distribute them: I had babies, I'm a happy plant. So it matches up with our biology in this bit of a symbiotic relationship, where as an animal I don't want to eat a fat-burning compound, I want to eat a compound that will help me survive longer. So I prefer the ripe fruit that is sweet, that is bright in color, that smells good, that is juicy and soft and delicious, and the more ripened that fruit becomes, the more of that signal comes with it. That seems to be why we prefer sweet, ripe fruit, and if you take that to the extreme, you juice it, you dry it, you put sugar into your food, because it's those properties we seem to be attracted to. A typical ripe fruit is not the biggest deal, it's a natural product that's got so much nuance to it, even as it ripens on the counter. But when we take it to the extreme, we're sending more and more of that conservation signal, which can eventually start disrupting how our body behaves.

17:45 Blackberries, tomatoes, and hyper-seasonal fructose

17:45Casey:Okay, you and your backyard, you've got the blackberries, me in Salt Lake City, I've got the tomatoes, we do awesome tomatoes around here. I don't do gardening myself, it's so much work and you get so little out of it, but we have community gardens all over where I live, and if somebody moves or doesn't take care of their garden, those tomatoes will just fall on the ground, and I'll have one or two of them, and they're absolutely delicious, they taste nothing like what you can get at a store. I'll never eat a store tomato because it grows, and I've used this example many times before: it'll start to be maybe this time of year, August, September, October, and we'll have a hard freeze at some point, and all the tomatoes will be gone. I still want tomatoes on that day. The problem is, I don't have them, and I'm not going to go to the store and buy gross, cardboard-tasting tomatoes. I could want the tomatoes as much as possible, they're not available to me for another ten months. Is that kind of the way we should be thinking about fructose, that this is a very hyper-local and hyper-seasonal kind of thing historically? And now, you live in Vancouver, you can go buy mangoes and pineapples any month of the year. Is that a different way to look at it?

19:06Chris:I think it's exactly the way to look at it, because if you think about the animal outside the door, they have this ebb and flow of availability. In summertime, going into early fall, we have these opportunities where it makes sense with the timing. Ahead of wintertime, when things are going to get really hard, I want to pack on what will help me survive that season of scarcity. That's what Dr. Johnson suggests, that this is a survival mechanism where during scarcity, or ahead of scarcity, homeostasis breaks a little bit, and this little survival system that's activated by fructose can help your body conserve. In summer, when that opportunity is there, it's going to switch on to help your body conserve. In wintertime, it's also going to switch on, because now that scarcity has arrived, and because of dehydration, because of an availability of certain stress signals effectively, it also snaps on so we can conserve what we already have. And then suddenly the biology of a bear makes a lot of sense, where they're binging like crazy in summertime, and then they don't eat or drink for six months. That's crazy, but it works really well for them.

20:11 Why bears and whales never need to drink water

20:30Casey:It blew my mind. This was not very long ago that I learned this, I never even thought about this. Exactly what you said, a bear won't eat, I knew that, but then somebody said that they also don't need to drink, and I was like, oh, that's super weird, how can you go that long without drinking any water? And you're right, the fat breakdown gives them the water that they need to not die.

20:46Chris:Exactly, exactly. We maybe don't appreciate that much, but the body is holding water in fat, and it's not until it's unlocked that it allows the body access. You may think of a whale, also really fascinating. A whale lives in salt water, it doesn't drink water. The only way it actually gets the water it needs, because it certainly does, is through its fat stores. So another crazy example, it doesn't drink water ever. The body is fascinating, it's pretty amazing how it uses all of these systems in a coordinated way in order to make sure it has what it needs, and some of it's going to mean conserving and managing those resources. Fructose seems to be at the linchpin of how those resources are managed.

21:40Casey:In what ways will the body become more economical? I would see it in my past life career, measuring people's metabolic rate using a metabolic cart. And sure enough, if somebody had done some type of calorie-restricted diet combined with lots of exercise, we would see that economical mode in the way they were breathing, and they just weren't burning very many calories. One example I give is I measured a woman who had just participated in, and got kicked off of, the Biggest Loser contest. Based on her demographic, her age, height, weight, and gender, her resting metabolic rate, the number of calories she should have been burning at rest was about 2000 calories, and we measured it at 1000 calories. So through doing the contest, which was notorious for tons of exercise and not eating very much, she lost a bunch of weight, but of course she gained it all back when her metabolism dropped. In what ways does the body become more economical?

21:40 Metabolic rate, economical mode, and mitochondrial fission

22:34Chris:That's a great question. From what I'm seeing, I think those data are a little bit tricky, because am I already in a conserving state when I'm starting to induce a change in my metabolism? I love that you're saying the metabolism is variable, because I think that's something we naturally know but also sort of push aside. Until I was about 25, when I got married at 22, I think I weighed like 135 pounds, and I was asking everyone at the gym, what do I do, I don't want to look like I'm drowning in my suit, I couldn't gain weight. That changes though. As I got a little older over the next five years, I think I gained like 30 pounds or more, not muscle, but it was just that things changed in the way I ate, what I ate didn't work with my biology anymore, everything slowed down. So I think that concept, that metabolism is variable, is super important to this. What Dr. Johnson's research seems to suggest is that mitochondrial fission occurs, and this is a concept I didn't really understand before. We will always appreciate mitochondria as little beans, that shape, but this is suggesting that a really healthy mitochondrial network, they elongate and start fusing to each other, into a network, and that little bit of extra allows them to work really coordinated and efficiently. They're pulling in all of that fuel, glucose primarily, and creating ATP in an amazing fashion.

23:38 Mitochondrial fission: a healthy network versus a stressed one

23:38Chris:The problem is that when we start introducing inflammation into the cell, and other things, especially through fructose, because that's sort of what this all chains up to, mitochondrial fission occurs, where they start breaking apart and don't work quite so coordinated. It's not saying it kills the cell, but it drops the baseline energy, maybe 20% or so. It's not going to say, okay, let's start doing autophagy and eating our body, devouring our muscle. But it's probably going to send enough of a signal to the brain that we need more fuel here, we're running a little lower than baseline. With that little drop in energy, suddenly we start consuming more, we activate cravings, and that whole experience of feeling tired and inflamed and craving becomes part of this puzzle, where our experience once our metabolism slows down is very easily explained.

25:24Casey:Yeah, it is. We could recognize it too, even before somebody ran a test, like a woman who would be wearing a jacket in July, always chronically cold, especially in the extremities. Somebody in that depleted state, the body is activating cravings, why, because it wants more energy, it's not getting the energy it needs. That body is also going to run cold, it's not burning all kinds of energy to make the body warm anymore. Or reproductively, there could be some changes. Can you talk about that as well?

26:02 PCOS reframed as PMOS

26:02Chris:Yeah, I find that one fascinating. I've been diving into low testosterone and PCOS, or PMOS, as it's been relabeled now, and it's really fascinating because it seems to be pointing to energy regulation again. If there are certain programs in the brain that I would call expensive, not necessarily survival-driven, like we need vision, otherwise we won't eat again as an animal, we need motor control, otherwise we won't eat again as an animal, those things need to be preserved. Even in Alzheimer's patients, they can still move, they can still see generally, but expensive programs begin to degrade, like short-term memory, or higher reasoning, or reproduction. That makes sense too, because if we don't have sex for a year, we'll probably survive, but it's not preferable, and this is maybe part of the same program, where if there's an energy disruption in the brain, we're going to triage how energy is allocated within the brain. That seems to be what's happening. When we have, for example, kisspeptin neurons that largely regulate reproduction, and those start to get a muddier signal of energy availability, it would make sense why downstream, maybe testosterone would drop off, or the confusion state of hormone dysfunction in PCOS would show up. If you're not getting that steady signal of hormones, the cycle of what's necessary to complete ovulation won't proceed the same way, you'll start getting an intermittent signal where maybe follicles won't completely mature, and then you start getting other challenges that come with hormone disruption for women. It seems to resolve a bunch of things at the same time. And of course, if this is an energy problem, it starts to explain the metabolic challenges that often correlate with that, where reframing PCOS as PMOS is really just saying this is also a metabolic challenge, not just hormonal. It starts to say, maybe this makes sense if energy is being triaged, not just in the brain, but across the body as well.

28:47Casey:Very unifying, like I said earlier. Thank you for explaining that. I maybe should have asked this question a little earlier in this conversation, but can you tell us the difference between how glucose gets in the body, how fructose gets in the body, where it goes, what it does? Why is it that we have continuous glucose monitors but we don't have continuous fructose monitors, that kind of thing?

28:47 Glucose in, fructose out

29:13Chris:That's a great question. Back to what we were talking about, if glucose is fuel, it's the body's preferred fuel. Typically what happens is it's bound up in glycogen, so it attaches a few molecules of water to it, and it's sort of stored temporarily. I like to think of it like the fridge, you just easily reach in and grab whatever you want, that's sort of circulating within the body. I think we can hold up to about 10 pounds of that, in the sense of the water weight we'd normally have to lose first. So that's easily used by the body. It's when that runs out that the body turns to ketosis and says, okay, I don't have glycogen around, I'm going to start breaking down fat to get energy out of that. I kind of like that frame, because then it starts to think of fat as the deep freeze, I need to melt it in order to use it.

30:04 Fructokinase, ATP, and the sugar crash

30:04Chris:On the other hand, fructose, when it's metabolized, not digested in the gut but when the cells go to use it, it's first broken down by an enzyme called fructokinase. What that does is it basically attaches a phosphate to the fructose, and that basically depletes your ATP. So whereas you get a little boost from the glucose with your ATP, you start to get a transient drop in ATP with fructose, which sort of explains why you get the high and then the low, the sugar crash from eating sugar: the glucose gives you the bump, and the fructose drops it. Suddenly you have less, kind of cool, so it's resolving how that works. Then what happens is that ATP, instead of otherwise being rechargeable, which is what your mitochondria do, boosting your ATP back up like a rechargeable battery would, what happens with this little deletion of a phosphate is the ATP degrades into ADP, into AMP, a diphosphate to a monophosphate, and then eventually into uric acid, where it's no longer rechargeable, it's now just a waste product that causes cellular stress. And it's that cellular stress that then downregulates your mitochondria, starts causing that mitochondrial fission to occur. None of that happens too quickly, it's not like there's this immediate, I'm going to eat fructose and suddenly my cells don't work as well. This is going to take time, load matters, and flux matters, and time matters, where if you send that signal enough, then it's not just a little drop in energy, but it starts to restructure the mitochondria downstream, and then suddenly everything starts running slower. That's partly why I think fructose has kind of gone under the radar, that timing does matter a lot. We've done studies where you give an animal a high fructose diet, and in a month it's like, yeah, nothing happened, but the same thing tested out for six months, a year, and suddenly they've got major metabolic dysfunction that started occurring. So there's a very different signal, the timing matters. When we look at it from our modern diet, if we're eating sugar all the time, constantly exposed to this low dose of a conservation signal where our mitochondria are downshifting, then suddenly everything starts to make a lot more sense, where the pathology is a natural reaction. You've got a fragile cell that can't support the system it's responsible for, like your liver, and suddenly the liver starts acting not so great anymore. We get fatty liver, it's not doing its job, and suddenly that starts to be labeled as disease.

33:12Casey:Got it, I'm glad you mentioned the liver, I was going to ask you that next. Before I do, just as you're explaining that, again, the seasonality of all of this stuff just makes so much sense, that yes, you can handle a lot of this for a short period of time, weeks, months. I know animal metabolism is a little bit different than human metabolism, but at least it points in that direction, that having a high amount of this for a month is really not that big of a deal if you then have a time where maybe you're getting a lot less or none of it. Can you go into greater detail and explain the connection between fructose and fatty liver disease, and why we're noticing so many people who are not drinking that are getting liver disease, at very young ages as well?

33:52 Why the liver is the first casualty

33:52Chris:Certainly. The most recent research is basically suggesting that non-alcoholic fatty liver disease and fatty liver, it's the same thing. In fact, Dr. Johnson's team released a paper in November that identified why it's the same thing, that alcohol is doing the same thing as fructose, which we've kind of had some indication of. There's research on this from about 15 years ago that basically, I think the headline was, fructose is alcohol by another name. But we didn't really understand the mechanism there. It appears to be driven by dehydration. Let's get back to that, because basically the takeaway is that the body makes fructose as well, so it's not just sugar that's the problem. But back to the liver: the liver basically soaks up, I think it's about 80% or so, of dietary fructose that makes it past the gut. So that's one of the reasons flux matters so much. If we're eating a big load of fructose, the gut is not going to handle it all, and it's going to go through the portal vein and basically encounter the liver, where that energy regulation signal is going to occur first. So that makes sense as to why fatty liver becomes the first casualty in this entire conversation: fatty liver is going to start appearing, all of that visceral fat is going to start appearing, and we start seeing the pathology. Then there's the downstream stuff of what happens after that, where the rest of the body starts to have the same encounter with fructose, but that's more of a downstream effect.

35:42 Other sweeteners and the taste-versus-energy split

35:42Casey:Do we know if any other sweeteners, whatever you want to call them, natural or artificial, do they also act in this way, or is fructose pretty unique as far as that goes? We've had Richard Johnson on our show, but we hosted him so he could promote allulose as this amazing sweetener, so there's some controversy there, not everybody agrees with him. What do you think about other sweeteners, do they act the same, or are they unique?

36:08Chris:I'm a big fan of allulose, I love it, I think it's fantastic, and I do think it's metabolically beneficial, which is actually the interesting part there. It's not just an inert, is this a good sugar or not sugar kind of conversation. I think what's here is implying that all of these things, not even just synthetic but alternative sugars, are they good for you or not, I think it's a good question. Ultimately my focus is on fructose itself, and I think there's a lot of nuance, maybe they'll do all these other things, maybe there's some slight toxicity that will be part of it, or a correlation with something. But I kind of would argue that most of that is noise. The question really is, is it sending my body a signal to conserve or not, because I think that's the big elephant in the room. If my body's not conserving, then I'm going to have the capacity to handle a lot more that's thrown at it. So I drink Coke Zero, I think it's delicious, I'm not afraid of it, I don't find that it gives me cravings, because that's a different question. Recently, Dr. Johnson just really beautifully explained that they did research that separated the cravings that come from your taste receptors and kind of the sweetness dopamine thing from the cravings that come from your liver, or from that energy-depleted metabolic state. It was pretty fascinating, because he basically gave, if I understand this correctly, rodent models a sweetness blocker or a fructokinase blocker, and they both still had cravings, but there was a very big difference: the sweetness part was basically identified as a preference, we like sweet foods, that's not going to change, but it's also not going to take away my agency, where I can still say no to sweet foods. Can't tell a rat to, but we can make that decision. But when the craving is coming from an energy depletion signal, that's more like an alarm the body doesn't have as much agency over. I can't really say no when my body thinks it's starving. So then the cravings, where we go and raid the cupboard late at night, start to resolve a little bit, where I can have super amazing discipline with 90% of my life, I can work out, I can get a lot done at work, I can make all these great decisions, but then with this thing, I have absolutely no control, I can't help but reach for the cookie.

38:52Casey:Well, you're mentioning cravings, and however you want to think about food addiction or whatever, you can't really think about food noise or cravings without talking about GLP. How does GLP fit into all of this?

39:06 GLP-1 drugs through the fuel-trailer analogy

39:06Chris:That's a great question. In my mind, GLP-1 medications are great, but I think they're kind of pulling on a lower lever. If the body can't help but refuel all the time, we're adding stress to the system, but I also don't think that fuel is what's wrong with your car. If your car doesn't run, I don't blame having too much gas in the tank. I think it would cause too much stress if I'm trying to pull a huge fuel trailer behind me as a little car, that ain't great. So I think removing the burden is going to make a big difference, but I kind of see that as being the role, and it explains why the weight regain happens so quickly when we go off those medications. It's kind of arguing, is the problem the fuel, or is the problem the engine, the mitochondria? If the mitochondria are repaired, if they run at a faster rate, then you're going to consume more fuel, and you're not going to be trying to refuel as often. So it resolves a little bit. I think it's great, I think it's taking a lot of pressure off the system, and even many of the effects we're seeing, I expected them, I kind of thought, yeah, this is going to start pulling on addiction, the craving kind of thing, and that's what it's showing, because it's taking pressure off, but it's not in a direct way, in the same way as fructose seems to be doing directly.

40:45Casey:I like that point of view, I'm glad you explained it that way. Is there anything else we need to talk about before we talk about potential solutions to all of this?

40:49 Endogenous fructose and the polyol pathway

40:49Chris:I think we covered a lot. I think probably the big one is talking about endogenous fructose, because the body makes fructose, so we can't just villainize sugar and say that's the only problem here. The body makes fructose in many of the ways that we kind of already are careful with. It uses osmolality, for example, to activate fructose metabolism, and that is basically going to be dehydration or too much salt. I know I shouldn't need too much salt, I know I should be well hydrated. If our blood senses that hydration is a problem by means of those things, it activates fructose metabolism, and in doing so, it starts messing with our nitric oxide in our blood, it makes our blood vessels tighter and less flexible, and suddenly hypertension starts to become a natural kind of endpoint of this. But the way that it does, anyway, no matter what, endogenous fructose is activated through the polyol pathway, and it needs carbohydrates to do that. So that's where your question about glucose monitors comes back into the story: anytime blood glucose spikes, that extra bit of fuel can be converted into fructose. It makes sense from a logical perspective, because if I've got extra fuel, I should store some, I should save it for later. So when that fuel level pops up, glucose is converted into sorbitol, and sorbitol into fructose, and then conservation appears, so we start storing some of that. So then high-glycemic carbs become part of this conversation as well, where the slow carbs might not be so much of a problem, but too much high-glycemic carbs starts to become a problem. It also becomes very relevant to the brain. Fructose doesn't make it through the blood-brain barrier, but glucose does, so how are they measuring fructose in the brain? It's obviously through the synthesis of fructose through high glucose levels. So suddenly you have this big picture where high-glycemic carbs matter, and salt matters, and dehydration matters, and even stress states matter, like hypoxia, where that will also activate endogenous fructose. And then you end up with an individual who is obese, who has persistently high glucose levels, who's chronically dehydrated because their glycogen stores are maxed out, and who starts to get hypoxia because they have sleep apnea, because they have too much weight on their chest. Suddenly they're a fructose-generating machine, and it keeps the body held in a conservation state even when they're really, really trying hard to moderate their diet and eat really healthy. So we get locked into these things where what I was doing before doesn't work anymore, because we've started activating the system from multiple angles, like an alarm system would be.

44:22 Keto and carnivore diets through the fructose lens

44:22Casey:Well, it's so fascinating that you explain that, because there's plenty of people who do what I choose to do, which is skip the whole thing, I'm going to have a very low to no amount of carbohydrate in my diet. I can make what I need to play my hockey games, I don't suffer performance-wise, I feel better just eating fat and meat and protein, having a very minimal amount of carbohydrates. But what you're describing, there's many different things in there that could impact somebody who's doing a carnivore diet, a ketogenic diet, that they should be absolutely mindful of.

44:52Chris:It's true, but I hope that gives an extra bit of validation to your approach, because if fructose is activated either through dietary fructose, which I imagine you're avoiding, you're not trying to eat too much sugar, or through high-glycemic carbs, a keto diet informs it very well: whether it's dietary or endogenous fructose, a keto diet seems to be a really solid way of pushing back on it. If you're going to take a dietary approach to this, that's a great one to handle. Unfortunately, most people can't live in ketosis for a really long time, it becomes very challenging, so I don't want to invalidate that either, but it's a smart approach to this. I hope it gives a new lens as to why this might be really effective for so many people.

45:42Casey:Sure, but again, the way you explained it, it could also explain why some people do stall on a carnivore diet. I know a lot of people who do carnivore, including myself, we don't get super shredded, we are generally healthy, but we don't get down to like 6, 8 percent body fat, so there's other components. The body starts pushing back and saying, okay, I want to hang onto this now, I'm hitting my max, this is the safe area.

46:03Chris:Yeah, absolutely. Some people do report they bring some fruit back into their diet and they feel a lot better, and it helps with hormones and all this other stuff. So again, a lot of context, a lot of nuance.

46:17Casey:You already mentioned the con to doing something like a ketogenic diet or carnivore diet, it's hard, it's just hard for a lot of people. I find it to be fairly easy at this point, I know what my food is and it's not that bad, but for a lot of people out there it's really challenging to do what most people would consider to be a very restrictive diet. So tell us about your product, tell us about your company and your product, what are the solutions you help people out with? I've got some right here next to me, your SugarShield product, we'll talk about it, but tell us how you found a way to add value for people and provide an answer to that particular problem.

46:56 SugarShield: finding luteolin and building the product

46:56Chris:Rewinding back then, remember, I read Dr. Johnson's book, and I was like, it's super cool, I'm going to take more vitamin C and try to restrict my diet, see if I can move the lever that way. It was about two years later that I basically came across more research where they started digging into the enzyme that is at the linchpin of fructose metabolism. You've got all this noise that's going to activate it, sugar, high-glycemic carbs, salt, all of it, it all depends on this one enzyme, fructokinase, in order to activate the signal. That's the enzyme that causes the uric acid in the cell that downshifts your mitochondria. Dr. Johnson's team is quietly really focused on finding and identifying a fructokinase inhibitor, because in the most recent podcast I saw with him, he suggested that's going to be probably the first prevention for Alzheimer's disease, the first real treatment, just as an example. If it's creating a conservation state, all downstream metabolic things are going to matter, right, if the body stops conserving, it's going to start using energy properly again across the board, whether it's the brain, the vascular system, the liver, all of it. So fructokinase becomes highly relevant. And of course, pharmaceutical trials take a long time, but one thing they do start with is an assay of botanicals, to figure out does any of this stuff actually move the lever. This is basically where I went back into the research and said, oh my goodness, this could be interesting, and I saw luteolin in there, which was identified as a potent fructokinase inhibitor in animal models. That was interesting to me because luteolin is already available as a supplement, it's a polyphenol, we've been taking it for, well, it's been part of our food for thousands of years, it's in celery and thyme and parsley and artichokes, and so much of the food we eat. And now we can buy it, it's not popular, but it's there. So I basically started experimenting with it myself, and it was pretty wild, within about three weeks I started noticing that energy rocketed and cravings dropped almost simultaneously. The same thing happened to my wife, and then the same thing happened to my in-laws, and I was like, okay, this is a really cool experiment, I want to see if this starts changing things for my friends. It went more and more from there, and it basically validated that it does seem to be pulling on the same lever in humans as the animal research was suggesting, and in a safe way, because it's three or four years later, and I feel fantastic still, that initial bump in energy is still there, I can have full agency over the food that I eat, my health has improved significantly. That's my experience, I'm not saying it's treating anything, but it's just really cool to see that it seems to be pulling on that lever of controlling fructokinase.

50:26Casey:Okay, so does it work in the way that you have better food control, and you're not choosing to eat foods with a lot of fructose in them that you may have eaten before, or is it that it allows you to have more of the fructose that you want and you're just not absorbing it?

50:38Chris:That's a good question. I think a parallel is that a lot of people will do a really restrictive sugar-free diet where they just won't eat sugar, and most of them don't last very long, but the ones that do, they start to notice the exact same things that I did. That was the really cool part, the inflammation in your face drops away, the inflammation in your body drops away, and you get more energy and start having more agency over your food choices. So I think all of that's very important. For a long time I tried to use it to enable a sugar-free diet, and then I started to realize I didn't need to. I eat sugar again, I don't intentionally restrict it, I eat healthy, I don't want it anymore, that's the cool part. Suddenly cake is often too sweet, I can't handle it. I noticed that with a number of people, after a few months your taste preferences seem to change, a strawberry blows your mind it's so good, and then cake or otherwise sweetened foods are just unpalatable, they're gross. So that was the cool part, it felt very liberating in a way, where I had this defense up against the effect of sugar, and I could sort of moderate in a way that almost seemed healthy again, where I didn't have to be so obsessive. That was the exciting part for me, that was my experience. Am I going to say that's the same for everyone? I do think there's value in both, I think using it in combination seems to be the right path, where this will take the load off, give you agency back so you can make better food choices, and you can probably have a bit of a caloric restriction that you can handle, so your body slowly gets toward a healthy state.

52:40Casey:Got it, I think there's power in both and using them together. I like that. So in that way, somebody could take your product for a temporary amount of time, maybe two or three months, cut sugar, and kind of slowly get off of it and see how they do, or is it something that people are going to want to take more long-term, and it sounds like it requires a bit of time for it to really start working.

53:10Chris:I think that's a really smart way to put it, yes. I think three weeks to a month seems to be on average what people will see as an effect, but I say give it three months, just because it seems inevitable that effects will come, that perceived effects will come, it just depends on your metabolic state. If I'd been burdening my body with fructose unknowingly for my whole life, and my mitochondria are basically running at a persistent low energy state, this is not going to stimulate something, this is going to hopefully take some of the burden off so that bit of restoration can happen on its own. Once it does, you're going to feel it, but that's going to take time, and it's going to be different for everybody. A few different people I've worked with have reported back like day one, oh my goodness, I slept so much better, I feel so much clearer cognitively, their experience was almost immediate, that's really cool. That's not going to be everybody, but it says a lot about how close you are to feeling really strong. I think it's just going to take a little more time for different people.

54:23Casey:Got it, okay, that's great. Have you talked to enough people who consume a diet like I do, that just doesn't have very much fructose in it, do they also notice quite a bit of benefit?

54:31Chris:I do think so, I think it sort of depends upon whether that system is being activated through a side door in a way. Some people that have a keto diet still are high in uric acid, which is an interesting thing, so it's coming from somewhere. I think this is suggesting that uric acid plays a very important role in this whole system, because that's causing the stress that's going to cause your mitochondria to slow down, which is why in our product we don't just have luteolin, but we also pair it with tart cherry extract, because it's been documented to help clear out some of the uric acid, to help the body flush it. That's going to speed up the restoration theoretically. I've got some friends that are basically performance athletes, and they take it more because they're curious to see whether they can improve their performance, the idea being the faster your mitochondria, the more glucose utilization you're going to have, the better performance you're going to have. So even from that level, it seems to be maybe doing some good stuff, where it's just going to make everything run more efficiently with a little bit of added defense.

55:52 A quick detour into resistance training

55:52Casey:Amazing. My bottle is still sealed, I didn't think it would be helpful for me since I didn't need any, so I am going to give it a try. I really appreciate that, that was very well explained, and thank you in advance for all the hate mail I get from all my carnivore friends for mentioning things like celery and cherry extract, I'm really going to pay the price in my inbox for that. This has been a fascinating conversation. I do have one more really selfish question to ask you, a little bit unrelated, but I find it interesting. You found in the past that you had a different body type, I would consider it like a hard gainer, or somebody that's really difficult to lift weights, you had some limitations with lifting weights, but you did find a way to do resistance training that wasn't as mainstream, and it actually worked really well. Can you tell us about that?

56:34Chris:Yeah, cool, I didn't know you found that out. So my first little foray into biohacking wasn't even this. It was sort of like, I couldn't work out without getting too much tension, and it was like, well, great, now my neck doesn't work and I've got to take a break. It was just like falling off the wagon so many times, even with a personal trainer. So I found a system, and I don't think there's anything wrong with saying what it is, because I don't have any association with them whatsoever, but it was the X3 system, where it's basically a bar that uses really high resistant variable resistance bands, latex bands. The argument there is that the muscle's strength curve is variable, where at rest you've got to be careful with it because your tendons can get overloaded, and at maximum contraction there's about a seven times difference in strength, and that's actually where you're training. The argument is that static weights are really inefficient for this, because you're either overloading your tendon or underloading your muscle. So in order to solve that with a heavy variable resistance band, you can have that lightweight where you don't feel sore anymore, because it's actually tendon injury, and then you can actually train the top end, and you do that with the aid of a bar and a base plate just to protect your joints. It was like, oh my goodness, that just made a huge difference for me, where suddenly I can work out regularly and feel good and give my body the right kind of adaptation I was hoping for. I'm not saying I made any huge gains, that's probably a different story, but at the same time I feel great because I can work out and I actually have some muscle definition that works for me. I actually feel strong again.

58:45Casey:That's amazing, thank you for sharing that. I will train anybody using whatever equipment they have, I've got access to great gyms, people have dumbbells and barbells and all kinds of different stuff. But when I tell somebody that I can go over to your house with a little bag full of resistance bands and I can train you very effectively, the number of eye rolls I get, it's like, give me a break, these stupid resistance bands. No, just give me a few minutes, try this, it's totally different. And you think about the way you were explaining the strength curves, it's so important. People don't think about it: when you load up a deadlift, say with a barbell from the ground, you're going to engage that weight, and that weight is going to be exactly the same whether you're bent over or standing up and you have all your mechanical advantage in that position. So that actually gets a little bit dangerous when you're pulling directly from the ground, because you're lifting the same amount of weight throughout the entire movement in your most compromised position. A band will be completely unloaded and then will load as you go. It's a total game changer, I wish more people would understand that. And then you see the horror videos of people who actually pop their pecs because the tendon snaps, it's horrific. But really that's because you're overloading that really weak part, the tendons, where it's trying to just hold everything together as you get to the top.

60:06Chris:Yeah, it's really interesting, I'm really grateful that I found it.

60:12Casey:Yeah, good for you. I've used X3 before, I've used a similar one, they're both great. You can also get bars, you can get plates, or just get the bands themselves on Amazon for 30, 40 bucks, really awesome.

60:25Chris:I have a cheap version too.

60:26Casey:Perfect, there you go. Good. Last one from me: what have you learned about frequency of strength training?

60:32Chris:Oh, that's a good question. I don't claim to be an expert on that, but I feel like you do need rest so that the body can rebuild the muscle. I like to think of it like sending a signal to the brain, because the brain is going to be the thing that says, hey, I don't have enough muscle, I need to grow more. So you want to send that signal through fatigue, basically going until you can't go anymore, and then you need to give it the fuel that it needs to build. So I think every second day makes a lot of sense. I don't think it takes very long to send that signal, but you need the right ingredients. I work out every second day, different muscle groups each day, but basically every second day the same muscle gets worked hard, and I try to support it with creatine, with essential amino acids, trying to give it the fuel it needs to do its job. But again, I'm not an expert.

61:38Casey:You sound like an expert to me. If this whole LIV3 thing doesn't work out, you can come move to Utah, we'll get you a Utah Mammoth jersey, we'll hire you here at Boundless Body. That was perfectly explained, we'll get you some clients. Thank you for explaining that, so much lines up with my experience and the things I've noticed with my clients: it's almost always less frequently over time than people expect, you don't have to be in the gym six days a week for an hour each time, it's about the signal that you send, and that requires a lot less time. So again, I know that was kind of a diversion, but I really appreciate your very thoughtful answer, and you make a great personal trainer. Chris, this has been amazing, I really appreciate you and your time and all the consideration you brought to this conversation. I think it's going to benefit a lot of people, so thank you so very much. Where can people go to find you and connect with you and your work?

62:27 Where to find SugarShield and the fructose model challenge

62:27Chris:Our website is liv3health.com, and that's where you can find SugarShield if that's what you're interested in. I also have a YouTube channel called The Fructose Model, that tries to dive into the insane amount of nuance of fructose metabolism, because I like to think of it, if this plays this upstream role, then it means it informs almost everything about metabolism and our experiences and metabolic dysfunction and so much of this. It's not focused on SugarShield, it's basically just trying to identify, does fructose hold up under scrutiny. I can't break it. We call this a model, but I've been trying to break it actively for about five years, and there's a page on our website that's basically just challenging anyone to give us some contradictory evidence so that we can look at it, because we can't find it. That's really exciting to me, because if that's true, then this is a major lever in our health and it affects almost everything. That's the most exciting part, because if we can move that needle even just a tiny little bit, then that matters to our family members who are suffering, who can't handle the restricted diets, and who are suffering from metabolic dysfunction that's making their later years just horrible. So I'm really hoping that it does just a little bit there.

64:01Casey:That's amazing information, it's so cool that you put that challenge out there. But that's again just totally validating and shows how amazing your work is. So we'll link all of that in the show notes. Thank you so very much, Chris, we really appreciate you, thanks for coming on the show today, that was amazing.

64:14Chris:Thank you, Casey, it was a great chat.

64:16Casey:Absolutely, had a great time. And this has been another episode of Boundless Body Radio.