Jay Feldman  0:05  
Everything you think you know about calories in, calories out, is probably wrong. I'll explain why that is in today's episode of the energy balance podcast, a Podcast where we explore health and nutrition from the bioenergetic view and teach you how to maximize your cellular energy, to maximize your health. In today's episode, we'll be going over whether calories in calories out is actually physiologically accurate. We'll go over the many misconceptions related to calories in calories out. We'll discuss why a calorie deficit is not required for fat loss. We'll discuss why calories in calories out does not mean that eat less and exercise more is good advice for fat loss. And we'll also discuss what most people miss when it comes to calories in, calories out, as always. To check out the show notes for today's episode. We're all linked to the studies and articles and anything else that I go over head over to Jay Feldman wellness.com/podcast, and with that, let's get started.

All right, so this is going to be a bit of a unique episode, or probably a two part series, for a couple of reasons. For one, this is going to be a solo episode with just me. And also, I'm going to be doing this in more of a presentation style, which, of course, is not typically how we do these podcasts, but it seemed to lend itself well to answering the question or these questions that we'll be going over related to calories in, calories out. It's just much easier to visualize and have graphics and kind of go through it all step by step. So that's what we'll be doing today. Of course. Let me know what you think. Let me know if you guys enjoy this styled episode? And you know, with that, let's jump right in. So basically, we're going to be going over a number of questions today related to calories in, calories out. And I wanted to do this for a couple of reasons. For one, I think most of the arguments out there on both sides are pretty surface level, pretty weak. I don't think people are really digging in below the surface and trying to understand both sides to the extent that one can, and really try to get down to the bottom of what we're even asking here, and then what the value is of these kinds of equations, you know, the calories in, calories out, equation that we'll get to. You know whether it's important for understanding what's going on in terms of body composition, whether it's helpful supportive of any certain modality or strategy. So we'll be talking about all those things, and in particular, I'm just going to list out some of the questions we'll be going over here. So the first question that we're going to be looking to try to answer is whether calories in, calories out accurately reflects physiology, and there's a lot that will that will dig into there, of course, when, and you'll see what I mean. But when I'm talking about calories and calories out here, I'm not going to be talking about it in the way that most people do, but we'll get into that. Next question we'll be trying to answer is whether calories and calories out is a helpful framework for conceptualizing fat gain or fat loss as well as energy balance, and is it the best framework? So, A, is it helpful? B, is it the best framework? And of course, this is a really important question. You know, second most important question to is it accurately reflecting life and physiology? And that's because, if it's not helpful, what is the value to it, or how much value does it have. And then we'll also be discussing what the alternative might be to the calories and calories out equation. Now a few disclaimers here before we dig in. So for one, I'm going to be steel Manning calories and calories calories out to a pretty extreme sense. I've never really seen anybody describe it in this way? So we're really going to be getting into the weeds and trying to create the best possible way to represent calories and calories out. This is very different from the way that most people conceptualize and apply it. And as we'll kind of start off with early on here, the way that most people describe calories and calories out, or try to explain it or or even thinking about it is really entirely false, and we're going to be digging beyond that to really give it a better shot at accurately representing physiology. Secondly, I will be criticizing many aspects of calories and calories out, but I want to disclaim here, because this is always one of the first things that people are kind of triggered to respond with. But what I'm not while I am going to be criticizing various aspects of calories in, calories out, this does not mean that. I'm saying that the amount of food that you eat does not matter. Those are two entirely different questions, of course, the related ones, and we'll be kind of parsing that all out as we go. But just want to get that out of the way. You know, in the beginning here, I'm not saying that the amount of food that you eat does not matter. All right. Second last disclaimer is that I'm going to be using various measurements and equations and estimations throughout the kind of presentation here, and that's really just to help illustrate the point. You know, it's really helpful to put numbers to you. You know, to the kind of more abstract things that will be going over here. But in order to do that, there's a lot of assumptions that are built into those calculations. And it's really impossible not to have assumptions built in, because, as you'll see, the kinds of estimations that we use get really in depth. So a lot of that is kind of estimated, to, you know, to a degree that still should be representative of what's going on, to, you know, a large extent. But they are still estimations. There's no way really for them to be exact. That's also part of the issue here, but I'll get to that. Lastly, is that the goal here is to discuss different conceptual frameworks, or basically changes in body composition, for fat, gain fat loss, for energy balance. And their relevance to physiology on a logical basis, right? Are these accurately representing physiology on a logical basis? Are they helpful on a logical basis? This is not some as much. We're not really going to be going over particular studies or mechanisms that are involved with different strategies here, that's really not as much what this episode is about. Prior on the podcast, we've done a few episodes talking about weight loss, various weight loss strategies and and ways to think about it, different things to consider, in terms of diet, lifestyle, sleep, you know, exercise, everything. And so I would go ahead and take a listen back to those. I'll link to those in the show notes if you're interested in more of the you know best strategies for losing weight, you know, losing body fat. But here we're really just focusing on calories in, calories out, and an alternative in terms of their value as conceptual frameworks. Again, just to the kind of last thing I want to mention here is that there's a lot of with, with, like with most things in health, whether it's, should we be eating carbs? Should we be eating animal foods? Should we be eating vegetable foods? You know, people get very defensive, and there's a lot of religiosity when it comes to certain ideas in the health sphere. This is definitely one of them, and we're really trying to look at this objectively. We're trying to keep our, you know, the emotional side out of it, and really just be open to looking at things as objectively as possible, and identifying whether they're really a accurate and B helping us or not.

All right, so let's begin, firstly, with the question of what is a calorie. So, very simply, a calorie is a measure of energy, and it has a very particular it's equivalent to a very particular amount of energy. It's this particular measure. And to be really specific, it's the amount of heat needed to raise one gram of water one degree Celsius. This is the definition of one calorie. Typically, when we're talking about calories in food, we're talking about kilocalories. So these are 1000 calories. That's what we're going to be using throughout the rest of you know these episodes is, you know, anytime we're referring to calories, it's in terms of kilocalories. And so we're just talking about a unit of measurement of energy, or, yeah, just a measurement of energy. We're not It's not anything beyond that, as we'll get to in a second. And it's worth noting that when we're talking about the calories, about the calories in food, specifically, these are just potential energy. This doesn't dictate anything about what happens with that potential energy once it comes into our body, doesn't determine whether it will be used to produce energy that we actually use, physiologically usable energy, which we typically call ATP, or whether its fate will be anything else, whether it's going to be used to produce muscle or bone or brain tissue, or it's just going to be excreted. The fact that there's a certain number of calories in the food does not dictate any of those other things. It is solely just a measure of potential energy. And it's also worth noting that that's not potential energy that we can extract all of so we can never extract all of the potential energy to food, because there's that's kind of the nature of any physical processes. There's a there's a loss of efficiency. The efficiency is not 100% and especially in the human body, it's not 100% so there's always loss as heat. There's always certain amount of material that we that as humans, we can't do anything with. We'll be talking about that too. So these are just measures of potential energy. Does not dictate what's going to happen with that potential energy. This is why we need to consider all those physiological processes that are involved when we're talking about calories in, calories out, just as a really kind of clear example here to drive the point home, if we look at this graphic as an example, the amount of calories and five pounds of spaghetti is enough energy. There's enough potential energy in there to brew a pot of coffee. Obviously you cannot put spaghetti into a coffee machine to brew coffee. The coffee machine cannot use that potential energy. But that is equivalent, right? These are equivalent in terms of calories. Same thing with one piece of cherry cheesecake that's enough to light bulbs for one and a half hours. Is a 60 watt bulb. It looks like, I don't know if that's actually, you know, accurate, or if it would be a lower wattage, not really the point again. Same thing with the Big Mac here, 217 Big Macs could dry, you know, have the same potential energy. Or the amount of energy required to drive a car, 88 miles, obviously, regardless of how many Big Macs you put in the fuel tank of your car, it will never work. It will never actually be usable energy for the car. And the same thing is true when we think about it in the other terms, in terms of what's going on in our bodies. So if we consume a liter of gasoline, that is the equivalent amount of energy as is in two pounds of body fat. But no matter how much gasoline you drink, that will never become body fat, right? Doesn't matter how many potential calorie or potential energy is in there, how many calories are in there, it's never going to become body fat. Same with grass, and grass is something that some animals do use to produce energy. Typically it's going to be, you know, ruminant animals that, you know, consume the grass and then it gets fermented in the in the intestines, or for them, they've, you know, multiple kind of chambers, and that produces short chain fatty acids, which are then absorbed and used for any sort of metabolic processes. But in our case, we could, can, you know, the equivalent amount of energy for one pound of muscle is contained in five pounds of fresh grass, even if we consume five pounds of fresh grass or 50 pounds, that will never become one pound of human muscle, because we can't use that potential energy in the grass. Now, as I'm getting at here, there's a large difference between the potential energy in a food and what's actually going to happen with it, whether we can use it or not. And that's definitely going to be coming into play here, because, just because, you know, we can kind of switch up the images here, but just because we consume a certain amount of Big Macs and it's the same amount of calories as a certain amount of body fat, doesn't mean it's automatically going to become body fat, same with muscle or any other human tissue or energy, right? There's no guarantee that the food that we consume is automatically going to become energy, all right, so the ways that most people use calories in, calories out, are not physiologically accurate. We're going to talk about a way that is at least close to physiologically accurate, or physiologically accurate. I don't want to spoil it, but we'll get there. But there are the way that the vast majority of people are thinking about it is very clearly not accurate. And so I just want to talk through some of those very obvious misapplications of calories in, calories out. We're going to touch on them here in some research that basically, very clearly illustrates that these are applications, that these are not accurate, these are not physiologically relevant, but people still say these things all the time as if they are true. So people will say things like, you know, the factors outside of how many calories you eat, your BMR, which is your basal metabolic rate and exercise, don't matter in terms of energy balance. Basically, these are the only things that really matter in terms of determining how much body fat you're going to gain or lose, or whether you're going to put on muscle, or anything else in terms of the question of energy balance, these are the only three factors that matter. This is obviously not true. There are tons of other factors that have massive implications here. We'll be talking about those. Another one is that the type of food doesn't matter only how many calories it has. Hear this all the time, you know, it's just calories in, calories out. So all that matters is how many calories you consume, and you have this set amount of how much you expend, and if you consume more than that number, you gain weight. If you consume less, you lose weight. That is an oversimplification to the point where it is entirely inaccurate. We'll be going through many clear examples and some studies about that as well. Next one, when and how you eat doesn't matter. Only the number of calories does. Again, the timing of when we eat has physiological implications. It will affect the outcome here, it will affect other aspects of the calories and calories out equation. And so if someone is saying that again, that is a misapplication of calories and calories out. Hormones don't matter when it comes to calories and calories out again, this one is, I think, a pretty obviously, a pretty obvious one, but hormones will have a huge impact on what is going on physiologically, what will happen with the potential energy in those calories, and will definitely matter, will definitely have an impact on this equation. So we'll dig into that as well. Sleep, nutrients, stress, etc, don't matter when it comes to calories and calories out this is another one that you know kind of was alluding to earlier. These things are all going to have a massive effect on all three sides of the calories and calories out equation. So if someone is acting as though they don't, they're and citing calories and calories out, they're definitely misapplying it or probably not thinking about it too in depth. Next one here, calories out is really only affected by exercise or activity. That one is definitely not true. There are a couple other very clear factors that are that fit on the calories outside that we'll be discussing here a few others, as far as obvious misapplications of calories and calories out, if you calculate your calories in and your calories out, you can determine the outcome this one, I'll kind of bookmark. We'll come back to it later. But the short. Answer is, even if you were to Cal to calculate both accurately, which is nearly impossible, but even if, even if you did, still doesn't mean you can determine the outcome. We'll discuss why that is next one. Here is an example of an application or a way that people will say calories in, calories out. They'll say calories in minus calories out equals weight gain or weight loss or a change in weight, this one is definitely not true, considering that weight in calories are not equivalent. Calories are a measure of potential energy, whereas weight is a function of mass and gravity, and they're not equivalent. As an example, one pound of pure protein is just over 1800 calories. One pound of pure fat is just over 4000 calories, and a pound of pure water is zero calories. So you could, you know, have the exact same calories in, calories out, and then drink, you know, one pound worth of water, and your weight will be higher despite the fact that, you know, that quote shouldn't be happening from the number of calories in or number of calories out. Again, you could argue that you had, you know, 18 and 18 under calorie surplus, and that still doesn't determine anything about weight gain or loss, because that could be one pound of pure protein gained, which is kind of irrelevant, because we don't store things as pure protein, but let's say we did, or it could be less than half a pound of pure muscle, or, Sorry, of pure fat. So those are two different weights, but those are equivalent in terms of calories. So again, anyone is saying that, you know, calories in minus minus calories out equals change in weight. That's very obviously not true. You know, we'll be digging in quite a bit deeper than that. Then sometimes we'll also equate it with body fat instead of just weight. So they might say, you know, calories in minus calories out equals a change in body fat. And then they'll kind of use other extrapolations, by saying things like, if you eat an extra 3500 calories, you'll gain one pound of body fat. Or they'll say something else, like, if you eat 500 extra calories a day for seven days, you'll gain a pound of body fat. If you gain an extra or if you eat an extra five calories a day for 700 days, you'll gain a pound of body fat. While it would be nice if it was that simple, I suppose, I guess I'm kind of glad it's not, but we'll talk about that. But it's, we'll just leave it at that is definitely not accurate, and it's that's pretty obvious, if you dig in a little bit to the research, but also just the conceptual frameworks that we will today, some other misapplications of calories in calories out.

So as I was saying, this one is calories in minus calories out equals a change in body fat, or really anything other than calories in minus calories out equals a net change in calories or a calorie surplus, calorie deficit. We'll be talking about why this is the only way that calories in calories out could be considered accurate is if it's said in this way that calories in minus calories out equals a net change of calories. We'll also talk about why it's not really saying all that much. It's it's kind of a circular statement, but that is the extent to which you can go if you're if anything else is placed in place of net changing calories, if it's weight, body, fat, muscle, anything else, there it is basically a misapplication of of a of calories and calories out. Now even the idea that a calorie deficit is needed for fat loss, or that a calorie surplus is needed for fat gain, is a misapplication of calories in calories out, and we'll explain why that is as well. That one will require that we get a little bit deeper. All right, so before we get into some of the research, basically going over the really obvious issues with calories in, calories out, as it's normally applied. You know, a lot of the things that we just kind of went over, but we're going to go through some research supporting it. I'm sure, if you're listening to this, you might be looking for some answers as far as fat loss goes. And it's also worth mentioning, as if it's not clear now, it definitely will be that what you eat matters, not just how much, not just the number of calories, and so when it comes to eating the right foods for weight loss or for fat loss, there's a lot of conflicting information out there. That's why I've created the energy balance Food Guide. This energy balance food guide helps you determine exactly what to eat, to optimally support your metabolism and help you lose weight, improve your digestion, get amazing sleep, boost your energy and so much more. The energy balance Food Guide is a one page infographic that organizes foods on a spectrum based on how effectively they support your metabolism, and it also has a separate spectrum that helps to adjust the scale for you in the case that you're dealing with various digestive symptoms, the food guide makes it extremely easy to get started with a bioenergetic approach to optimizing your health. So head over to Jay Feldman wellness.com/guide to download your free energy balance Food Guide. All right, so let's dig into some of the research going through the general issues with calories in, calories out as it's typically applied. We're gonna start with the basics in terms of human physiology and bioenergetics, which might not sound particularly. Really basic, but we'll break it down here. In this first quote, they state, it is increasingly clear that the idea that a calorie is a calorie is misleading. Different diets lead to different biochemical pathways due to the hormonal and enzymatic changes that are not equivalent when correctly compared through the laws of thermodynamics, unless one measures heat and the biomolecules synthesized using ATP. It is inappropriate to assume that the only thing that counts in terms of food consumption and energy balance is the intake of dietary calories and weight storage. So we will be exploring all of these concepts in more detail. But what they point out here some really important things, a that different biochemical pathways are not equivalent when corrected, compared through the laws of thermodynamics. So whether we're using different substrates, you know, carbs or fats or protein to produce muscle, to produce skin, to produce energy, these are not equivalent pathways. We don't use all these things with the equivalent efficiency. They're, as they said, different hormonal impacts, enzymatic differences, and all of these fall within the umbrella of thermodynamics. Some people will cite just thermodynamics as support for calories in, calories out, but all of these things fall under that umbrella and need to be considered as they kind of stay here, unless someone measures heat and the biomolecule is synthesized using ATP, it's inappropriate to assume that the only thing counts is the dietary intake of dietary calories and weight storage. We'll be talking about that and and why. This is one of the really, one of the things that's really ignored when it comes to calories, and calories out one of the things that people don't really discuss, and that's because it makes it a lot more complex and basically inapplicable, really hard to measure, really hard to use to tell us anything. And but in any case, it really needs to be considered if we're going to talk about it accurately. Next quote here states a review of simple thermo thermodynamic principles shows that weight change on isocaloric diets is not expected to be independent of path. By path, they mean the metabolism of macronutrients, and indeed, such a general principle would be a violation of the second law of thermodynamics. The second law of thermodynamics says that variation of efficiency for different metabolic pathways is to be expected. Thus, ironically, the dictum that a calorie is a calorie violates the second law of thermodynamics as a matter of principle. Again, saying something very similar to that first quote that we have where, essentially we need to consider the difference in efficiency with which we can use the potential energy in the food, considering that we're talking about all this happening inside of human physiology, as opposed to just, you know, inside of a bomb calorimeter, and that this is something that basically is dictated by the second law of thermodynamics. So we need to be considering this. These things all right. Then lastly, ingestion of the particular so this was a this was a study looking at processed food versus whole food diet, and they say injection of the particular processed food meal tested in this study, decreases postprandial energy expenditure by nearly 50% compared with the ISO energetic whole food meal. This reduction in daily energy expenditure has potential implications for diets comprised heavily of processed foods and their associations with obesity. So we have an example here discussing the impact of the same number of calories on, in this case, calories out, so to speak, on energy expenditure. And that's something we'll be talking about quite a bit, but it's an example, basically, you know of these first two quotes, and in this case, they're not even talking about differences in macronutrients or anything like that, just whole food versus processed food, keeping it isO energetic, ISO caloric and showing major differences in other parts of the calories and calories out equation. So again, this is why the way that most people are applying calories in, calories out, it's really irrelevant, and this is also why we need to be considering a lot more factors if we want to talk about it in a way that's physiologically accurate. All right. So moving on here. A couple other quotes, things to consider when it comes to human physiology, bioenergetics and thermodynamics. This quote states asymmetric nutrient energy partitioning describes the context dependent cell specific competition for calories that determines the partitioning of nutrient energy to oxidation and ableism and or storage. Just to pause there, what we're talking about here is that is a, you know, they're describing the fact that there's a likelihood for calories to, you know, potential energy and food, which is not just energy, but this, but basically the components of the food to be used for building structure or to be stored or to be used for fuel, you know, to produce energy. And there's a difference. It's they describe it as being asymmetric, both in terms of the types of tissues that will take up the components of the food, but also in terms of the likelihood of certain components of food to go toward something like anabolism versus oxidation. Yeah. They go on to say and effective calorie intake, which describes the number of calories available, available to constrain energy intake via the inhibition of the sensory, motor, appetitive cells and the liver and the brain that govern ingestive behaviors. So we'll be coming back to this a bit later on, talking about the relationship between how many calories we eat and energy production and hunger. But what they're saying here is they're they're describing, or they're kind of coining a term of effective calorie intake, which is basically describing the the particular calories, or the amount of calories that's actually going to help to inhibit appetite, to actually help and reduce our hunger when we eat it, which is not all of the calories, certain calories are more likely to do that than others, is essentially what they're getting at. And they go on to say, we posit that the availability of nutrient energy to each cell is constrained not only by ingestive behaviors and total energy intake, but also by the context dependent asymmetric competition between individual cells. Thus, when energy sensing appetitive cells in the liver and brain are out competed by other cell types, like fat and or muscle cells, the effective calorie intake of a meal is diminished, and total energy intake will be increased to compensate for the deficit.

So what they're saying here is that depending on your physiological state, your the fuel that's coming in might be more likely to go to, let's say, the fat cells, and in that case, if the liver and brain aren't getting the feel that they need, you're going to remain hungry because they're not getting that, they're not producing enough energy. And that's really what they what they need from the food that's coming in. And there's a lot of physiological principles that will determine whether the food that's coming in is going to be really likely to be stored as body fat, instead of, let's say, going to the brain to produce energy. And we need to consider those things. It's essentially what they're saying here is, any you know, if we're going to have an equation or a conceptual framework for considering body composition changes, we need to consider consider things like this. How likely you know would certain you know, fuel types or components of food be to produce energy versus be stored as as body fat, versus going to the muscles and being used for energy there. So those are things that we would need to consider and make sure that we're encapsulating or encompassing in any framework. And then the last quote here, they state, the folk belief that overeating causes obesity has influenced clinical thinking with remarkable tenacity, despite two fatal flaws in the theory. First, the proposition is logically vacant. In as much as the definition of overeating is circular, only if one is fat can one be said to have overeated. So we'll just pause there. What we're talking about here is the idea that we've, you know, if we're gaining body fat, we must have just been eating too much. This is something that people will say, and then they'll cite calories in, calories out. And one of the, you know, one thing that's being pointed out this quote, is that the there's, there's, I mean, they describe it as being logically vacant, which I think is a great way to describe it. There's basically it, you're there's a circular definition here. It doesn't actually mean anything to say that you've overeated If you've gained body fat. So if you've gained body fat, you've overeated. You would need to be able to define these things independently. You'd have to have another way to define overeating, instead of just saying that it is defined by the fact that you've gained body fat. And this happens a lot. When people discuss calories and calories out, as they'll basically say, if you gained body fat, you were in a calorie surplus, or if you're in a calorie surplus, then you can gain body fat. But it is nowhere near that simple, and there's basically a lack of of value to those statements. They don't have they don't hold any any logical value. They then go on to say, second, whenever the proposition has been reframed so as to have meaning and then tested in a well designed experiment, eating behavior has appeared to be the dependent variable rather than the independent variable. So what they basically described here is that when they try to test the effects of of overeating on or the amount that you eat on body composition, what they essentially bind is that they they'll see a change in weight and then say that then the person was overeating, as opposed to being able to define that someone overeat, and then see the change in body fat. All right, so let's continue with some other general issues with calories in, calories out, as it's typically implied, and these come down to measuring calorie intake, absorption, digestion and excretion. So these are things that are often not considered, but are pretty significant issues that we want to be thinking about. So in this first quote, they state the present study analyzing 350 samples comprising 70 different products for nutritional compounds, declare that on label is the first larger attempt to quantify the precision and nutrition labeling of food products on the Australian market, the significant discrepancy between actual and declared values was detected with an average variation in precision of minus 13% to plus 61% for individual nutritional components. There is no tolerance limit established in the Australian food legislation. Million but a 20% discrepancy is allowed in some countries and others have separate upper and lower limits and allow maximum discrepancy of minus 20% for beneficial nutritional compounds and plus 20% for unfavorable compounds. Only 16% of the 70 products in this study would fully comply should a leeway of plus or minus 20% be introduced for any nutritional compound on the label. So in this study, we're talking about basically the differences between what's on a nutrition label and what's actually in the food. So we might think that we're doing an amazing job of counting our calories, and we copy it right from the label to our food, but there can actually be massive differences, and in this study, they're looking at all different nutritional components, not just calories, but calories are one of those, and they can be off by quite a bit. And as they described in most countries, they can be off by as much as 20% without, you know, while still falling within the kind of legal bounds like that that's still allowed legally. And of course, that doesn't mean that the companies are staying within those legal bounds, but that's what the what the legislation dictates. So you might be saying that you know, you might measure every single calorie you take in from your nutrition label, but it could be off by 510, 15 or 20% at least. So that's something else to consider when it comes to calories in, calories out and in this next one, this next quote, we'll be looking at something similar, where they state the energy content of almonds of the humans diet. In the human diet, was found to be 4.6 plus or minus point eight kilocalories per gram, which is equivalent to 129 calories per 28 gram serving. This is significantly less than the energy density of six to 6.1 calories per gram as determined by that water factors, which is equivalent to an energy content of 168 to 170 kilocalories per serving. The Atwater factors, when applied to almonds, resulted in a 32% overestimation of their measured energy content. So the Atwater factors are basically what we use currently to estimate calories in a food based on the assumption that, you know, every gram of carbohydrates is about four calories, every gram of protein is about four calories. Every gram of fat is about nine calories. And there's, you know, small variation there. But what they're saying is even using that assumption, that basically equation or assumption built, you know, in by various calculations, that there's a 32% overestimation for almonds, so the label on the food might be even considered to be correct based on the legislation, because the legislation would be using the Atwater factors. But that water factor is used could be totally off, in this case, by as much as 30% which is a massive, massive amount. So even if you're weighing the amount of almonds that you have, and you put it in on a tracking app, and it tells you you have this many grams of, you know, carbs, fat and protein, and it gives you a certain number of calories, that could be a 30% overestimation of the number of calories that are actually in there. So these are, we're not talking about little even, you know, even a couple percentage points would matter here, because over the long run, that could be a huge difference. But these are not small differences. These are massive, massive issues when it comes to calories out in practice, of course, not necessarily in in cons, you know, in terms of its conceptual framework. But we'll get to that. Alright. So next up is talking about some other aspects here that do need to be considered when, you know, just thinking about calories and calories and calories out conceptually in terms of absorption, digestion and excretion. Here they state, the human body, however, is not a perfect engine, and thus the thermodynamics may not be so pure. It is now known that the energy liberated from the combustion of a food is not identical to the energy available to the body from consumption of that food. This is the concept of metabolizable energy, or the difference between the gross energy as measured by bond calorimetry of consumed food and the energy contained in feces and urine, also measured by bond calorie calorimetry, others have since found that the Atwater general factors overestimate the measured metabolizable energy of mixed diets, especially those high in dietary fiber, by a mean of 6.7 plus or minus 4.4% with a range of 1.2 to 18.1% so essentially, because there's the excretion of a significant portion of of potential energy from the food in the stool and in the urine, there's a pretty significant overestimation of The, basically the amount of usable calories in food. So you could be thinking you're eating 2000 calories and expending exactly 2000 but of the 2000 you're eating, you could be only absorbing 1900 there. And that would put you hypothetically in a 100 calorie deficit that over, you know, every month would could lead to a nearly a pound loss of of body fat. So these are, again, some pretty significant factors that need to be considered when we're thinking about calories in calories out. Conceptually, it is also one of those factors that adds to the complications of actually applying calories in calories out. Here's the next quote, which states there was a large inter individual range for the percentage of calories lost at stools between 2.1 and 9.2 Percent on a 2400 calorie diet and between 1.6 and 7.6% on a 3400 calorie diet. In addition, calories in urine were not different between lean and obese subjects when expressed as the percentage of adjusted calories with either the 2400 calorie diet, where the percentage was about 3.2% for Lean compared with 3.5% with obese subjects, or the 3400 calorie diet, which was 2.8% compared with 2.9% so we're talking about here is basically that not only is there a lack of of consideration for the amount of calories excreted or lost in stool or in urine, but also there's inter individual difference. So you might excrete, let's say, 8% of your calories in your stool versus someone else might excrete 3% that's a difference of 6% which is a massive percent of total calories, you know, massive, massive amount of calories that we're talking about here on a day to day basis. When it comes to urine, they found that on average, was about 3% excreted, and there wasn't too much variability in the subjects that they measured.

But you know, this is something that needs to be considered with the conceptual framework. Again, makes it nearly impossible to measure calories and calories out, or apply calories and calories out. So that brings us to metabolic adaptation, behavioral compensation and the constrained energy model, and these are factors that will affect more of the calories outside of the equation when there are changes in calories in so again, we have this idea that you just manipulate the calories in calories out is going to stay the same based on how much you exercise or what else you do in a day, and then there will be this clear difference in calorie in the net change in calories, right? You had 300 calories fewer that day. Your calories out say the same. So now we're at a net deficit of 300 calories. But the reality is very far from that, and that's because the differences in calories in will then affect the calories out pretty dramatically. This is, again, we're not talking about small numbers here. Here's an example where they state that overfeeding studies indicate 96% less weight gain than expected if no compensation occurred. Dietary restriction and exercise studies may result in up to 12 to 24 sorry, 12 to 44% and 55 to 64% less weight loss than expected, respectively, under an assumption of no behavioral compensation. So this first quote here is just talking about behavioral compensation, compensation, which is basically that if you eat more, your body is more likely to move more. And this is voluntary movement, like you might be more likely to go for a walk or do some exercise, but also involuntary movement, which is just the small movements that you make when you're, you know, sitting at your desk or standing and tapping, anything like that, there is such dramatic behavioral compensation that, as they say in overfeeding studies, where you're eating more calories, you're trying to increase your calories to see weight gain. Let's say you increase your calories, just for the sake of it, by 3500 calories, thinking that you'll create one pound of body fat. Those studies indicate 96% less weight gain than expected if no compensation occurred. So basically, if you consume that same 30, 3500 calories, instead of that becoming one pound of body body fat, it becomes point 04, pounds of body fat, 96% less, just based on behavioral compensation. And then on the other side, in terms of lowering calories in or increasing exercise, they find that there's way less weight loss than expected. Let's round it to kind of 50% basically, they say, well, in terms of the dietary restriction, when they say 12 to 44% so even if we called it 25 you know, just kind of on the on the lower end there, that's still massive, right? So we reduce our calories by, let's say, 400 calories. So we think we're in a 400 calorie deficit, but because we then move less throughout the day, it actually becomes a 300 calorie deficit. And then, in terms of exercise studies, what they find is that you exercise more, and let's say you created a 400 calorie deficit, but the our bodies compensate by then moving less the rest of the day, which, if we rounded this to, let's say, 60% now we're at what 180 calorie deficit, give or take, is not exactly that, but less than 200 calorie deficit instead of a 400 calorie deficit. So massive changes in terms of the calorie outside due to just behavioral compensation. And then this next quote, they go on to say a common rule of thumb used for decades to predict weight change outcomes is that losing or gaining one pound of fat requires a deficit of 3500 calories of energy. This rule does not consider that human energy balance is a dynamic and adaptable system, or that lean and fat mass is lost during negative energy balance, and this leads to an underestimation of the change in energy intake or energy expenditure needed to produce weight change. So what they're bringing here in addition to the behavioral compensation, and then we'll get into metabolic adaptation in a moment. But in addition to that, when there's a change in body composition that also affects the amount of energy expenditure, because. If you have less muscle mass, it's going to reduce the amount of, you know, fuel that your muscles use on a day to day basis. So maybe, you know, you lose the first pound of of of mass, relatively easy, but some portion of that is muscle, and as that goes on, your calories outside of the equation continues to decrease. So that's one thing that they're discussing here as well. But there are also factors in terms of metabolic adaptation that go that are kind of independent of the behavioral compensation or change in body mass, and they describe that here. They say key factors of this problem are an adaptation of energy metabolism, especially resting metabolic rate, non exercise thermogenesis and diet induced thermogenesis, the extremely high failure rate of over 80% to keep the reduced weight after successful weight loss, is due to adaptation, sorry, is due to adaptation processes of the body to maintain body energy stores. This, so called adaptive thermogenesis, is defined as a smaller than predicted change of energy expenditure in response to changes in energy balance, a reduction in body weight of more than 10% regardless of whether in obese or slim individuals, is accompanied by a drop in total energy expenditure over 24 hours of approximately 20 to 25% this actual drop in 24 hour total energy expenditure is therefore twice as high as The theoretically expected value which results from the changes in fat mass and lean body mass would result. So what they're saying here is that if you lost 10% of your body weight, you might expect that your, you know, the calories outside the energy expenditure side, so to speak, decreases by 10% what they actually find is it decreases by more like 20 to 25% so over two times as much as is expected. This is due to certain, basically, metabolic effects of the weight loss, effects on thyroid and hormones, stress hormones, things like that, as well as the change in mass, as well as behavioral compensation. These are all things that would need to be considered in calories and calories out. And very, very rarely are and not to mention they're nearly impossible to account for. You know, it's nearly impossible to estimate these things accurately. So moving on here, we have basically an example of this, looking at weight loss in rats. And this is an incredibly telling study. And what they state here in this quote, is that there were three groups of adult male sprag dolly rats, Chow controls is the first group. This was a normal weight control group fed Chow throughout. The second group is an obese control group. These are animals fed a high fat diet throughout. And third is an obese cycling group. So these are obese animals that were cycled through two bouts of calorie restriction and refeeding so they lost weight, regained it, lost it, regained it. The cycled animals showed significant increases in food efficiency, meaning the amount of weight gains per calorie of food taken in and the second restriction and refeeding periods compared to the first IE, weight loss occurred at half the rate and regain at three times the rate in the second cycle, several physiological changes were associated with the cycling effect at the end of the experiment. At the end of the experiment, cycled animals had a four fold increase in food efficiency compared to obese animals of the same weight who had not cycled. So the numbers here that we're talking about are staggering. Again, just to repeat them, they were talking about how the animals that had cycled increased the amount of weight gain per calorie taken in and also basically lost weight slow slower, so they regained it faster. Lost it slower. The weight loss occurred at half the rate and the regain at three times the rate in the second cycle. So after one cycle of losing a lot of weight and regaining it the next time with the same calorie deficit, the weight loss occurred at half the rate. So basically, it required double the calorie deficit for the same amount of weight loss, and the regain of weight occurred at three times the rate. So it required 1/3 as much of a calorie surplus to regain the same amount of weight. This is like the these numbers were, again, we're not talking about a couple percent here or there, which according to the calories and calories out zealots who say, you know, 50 calories here and 10 here. And then you add it up, and you're, you've gained, you know, 50 pounds over 10 years, or whatever it is. The the people who are talking about those small amounts here and there are typically completely ignoring things like this as to how likely we are to store body fat based on what's going on metabolically, what's going on physiologically. And these things are entirely ignored by the vast majority of people when it comes to calories in, calories out, basically, they treat it as though there is this, you know, the calories in is basically fixed at whatever you ate, as if we could even measure that accurately calories out is fixed based on your energy expenditure, your exercise, whatever, and then there's just this pure net change in calories, and that determines exactly what's going to happen in terms of your body fat. And what we're finding as we dig deeper and deeper here is that it is way more complex than that.

All right, so another quote. Consider here coming back to the weight cycling, they state the physiological changes associated with weight cycling, such as energy expenditure, metabolism and fuel utilization, have been documented using a rat model. McLean and colleagues have documented the physiological alterations occurring in obesity prone rats that contribute to the rapid, efficient regain during relapse following weight loss and maintenance, the focus had been on the energy gap created during a period of calorie of caloric restriction that is characterized by decreased energy expenditure and an increased drive to eat. They found that in addition to changes in energy intake, alterations in metabolic efficiency and fuel utilization, factoring carbohydrate favoring carbohydrate oxidation, may significantly affect the propensity to regain weight. For instance, in the 16 weeks following moderate weight loss, weight loss of 14% of body weight, food efficiency was increased tenfold upon the first day of a 56 day refeeding in weight cycle rats compared to rats with established obesity. While this dramatic rise was reduced, was reduced within several days. Food efficiency remained elevated above levels in obese mice for the first four weeks of relapse. The most dramatic changes occurred during the first week of relapse, a time when nearly 40% of lost weight, which was primarily fat, fat mass, was regained. Researchers also noted that as the length of maintenance increased, the amount of weight regained, the amount of weight regained upon relapse also increased. Furthermore, regain was accompanied by a 30% increase in adipocyte concentration per fat pad. So a ton of things to get into here, but the short of it being that basically, after having lost weight, you'll see things like and they aren't talking about this specifically, but we have many, many podcast episodes, you'll see things like decreased metabolic rate via lower thyroid hormone activity, increased stress hormones, massively reduced efficiency of energy production, increased storage of of food coming in as body fat, massively increased appetite. We talked about these things in those previous weight loss episodes. We talked about in terms of the Minnesota starvation experiment, which was very clear about this, there's tons and tons of examples about this. And so if someone is taking the kind of oversimplified, clearly inaccurate version of calories in, calories out, and they're telling you, it doesn't matter whether you have just lost 50 pounds, or what diet you were on, or, you know what, whether, like, where your thyroids are or your hormones are at. If none of those things matter, we just need to look at your current calories out and look at your calories in, and create a deficit. And, you know, 500 calorie deficit a day, and in a week, you've lost a pound of body fat. If they're saying that, they're ignoring all the research, basically. And, you know, that's, that's basically what they're showing here. That's the short of it. And one thing that's notable is that they did mention that, what was it that, you know, some people would think if you keep the weight off for longer, you won't be so prone to the regain but they actually found that not to be the case, that when they where was the line? Researchers also noted that as the length of maintenance increased, the amount of weight regained upon relapse also increased. So basically, when they maintained the lower weight for longer, they actually regained even more weight when they relapsed. So again, the opposite of what many of us are told by the people, in favor of calories in, calories out. These things absolutely have to be considered anytime we're talking about body composition or having any conversation about these things. All right, so to continue on a little bit here, as far as these other issues with calories and calories out goes, we have or go we have the constrained energy model. This was popularized by Herman pontzer. We've talked about it in a couple of episodes previously, so I'll link to those. But we have a nice graphic here, graphs basically depicting it, which is basically that on the left we have what's called the additive model of energy expenditure. This is what most of us are told, which is that if we increase our exercise calories, let's say our normal calories out is 2000 and we increase our exercise by 500 calories, well then we burn 2500 calories. And if our normal metabolic rate is 2000 and we exercise for 1000 calories, then we burn 3500 calories, or, sorry, 3000 calories. But that's not actually what we find. Instead, what we find is is what's explained here in the constrained model of energy expenditure, which is basically that as you exercise more, not only is there behavioral compensation causing you to reduce activity, but there's also less energy used for other factors of our physiology, like maintaining the structure of, let's say, our skin or our immune function or digestion. Basically, instead of this additive model where we just burn more and more calories our bodies basically recognize that this is not a sustainable way to function, that this is going to cause major, major issues. Are basically going to starve. So we need to turn down our metabolic rate. We need to turn down the amount of energy that we put toward all of our other functions. And so those all get turned down. And, you know, we've increased. Our exercise, let's say, by 1000 calories. But instead of burning 3000 we only burn 2500 and that other 500 calories. Instead of going 2000 to 3000 we go 2000 to 2500 those other 500 calories are coming from other what I call internal demands. We'll talk about this a bit later. But essentially, these are coming from our organ functions and other regeneration that we need, and our cognitive function and things like that, where basically our body turns down those other things by lowering its metabolic rate, kind of going into a hibernation state in the extreme version, and that way it doesn't continue to expend more and more calories. So that's the constrained energy model. And here's another example, kind of describing it here and showing a relationship between how much activity someone has and the amount of calories it actually leads to in terms of total energy expenditure. And what they state here is that energy balance models focusing solely on the effect of physical activity on total energy expenditure, while ignoring the interdependent and dynamic role of other organ systems, will miss a large portion of the variation in daily energy requirements and may provide a biased measure of total energy expenditure, as shown here, additive total energy expenditure approaches will tend to underestimate the effect of physical activity total energy expenditure at low to moderate levels of activity and overestimate the effect of physical activity at higher levels, at higher activity levels, and so we basically see that pretty well depicted in both of these in the top one, what we're seeing is that as physical activity increases along the x axis, the total energy expenditure along the y axis does not increase at the same rate. It starts to level off. You know, that part was kind of shown a little bit clearer here in this prior figure. But then on the bottom here, we have the CPM per day, which is basically a measure of the amount of physical activity. And as the physical activity increases, the actual amount of expenditure decreases per amount of activity. So at very low rates, we actually increase our energy expenditure considerably. But as our as we exercise more and more the the amount that that increases, our total energy expenditure decreases massively. And that's because it starts to, kind of cuts into, starts to cut into those other organ systems, as was described here in the quote. So to summarize all this research and put it into an equation that includes calories and calories out and accurately represents physiology, we're going to do that now it is possible. It doesn't mean it's relevant. Doesn't mean it's helpful, but it is actually possible to incorporate all of the possible factors that we discussed and put it into a, quote, calories in, calories out, equation that does accurately represent physiology, does accurately represent everything that we discussed.

So in order to do this, a the equation would have to be calories in, minus calories out, equals net change in calories, as we described earlier, and we'll continue to describe this doesn't mean anything in terms of weight, body fat. It just means there's a net change in calories. And there's a lot of things we have to consider. So when it comes to calories in we're going to put this out in some in some numbers here, just as an example, so that we can kind of conceptualize all the things that have to be considered. So we're going to assume that we consumed 2200 calories, but then we have to consider that of those calories, 200 did not get absorbed. So we only have 2000 calories of actually absorbed food. We're going to put those calories, you know, we're going to associate them with macronutrients. So we're going to, we're going to say we have 500 calories of protein, 750 of fat and 750 of carbs. Now, one thing I didn't include here, and this is just one example of something else in the calories and equation that wasn't mentioned in any of those studies, is that if we are consuming fiber at all, and it's feeding bacteria, those bacteria can produce short chain fatty acids that we can then absorb. Those short chain fatty acids count as calories in I don't know anybody who is measuring the amount of short chain fatty acids that they produce and absorb every day and putting that in their calories inside of the equation, but if you wanted to do this, you would absolutely have to include that there. And there's some other ways that we could absorb small amounts of calories as well, like through the skin. If you're putting fat on your skin, it wouldn't be a lot, but you would absorb some, and that would count as calories in so there are some other things that would need to be considered, but we're even going to keep it at a simplified version here.

So then we have the calories outside, and let's say that we had a total of 2300 calories out. And of the 220 300 calories, the way we got to this is we considered all of the possible factors that we could, like the 200 calories that were not absorbed, and instead were excreted via the urine, breath and stool. So that's how we went from the calories in 2200 to 2000 those two 200 calories, those fall into category the calories out side. In addition, we would need to know our exact basal metabolic rate, and this would have to account for all the factors we described. So this would have to account for metabolic adaptation or hormonal status or sleep stress, whether we had previously been losing weight, uh. You know, what age we are, all sorts of things. And it would need, and this could fluctuate on a day to day basis. It can fluctuate based on the type of food that's coming in, how much is coming in. So we would need to somehow, obviously, this is impossible, or nearly impossible, definitely impossible for the average person without tons of equipment. But we need to be able to know exactly what the basal metabolic rate is, considering how much exercise we did, how much food we had, the types of foods we had, the macronutrient breakdown of the food we had, how well we slept the night before, our hormonal status, and on and on and on. But let's say we did that and then we knew that we burned 200 calories of exercise, which you could say is maybe this is an easy one to measure, but it's really not if you think your Fitbit, or, you know, Apple Watch or whatever, you know, there's tons of different ones. They're not particularly accurate when it comes to measuring your your calorie expenditure during exercise. They can be off by massive amounts. But let's just pretend that we were able to measure the exact amount of calories out during that point, and then we were also somehow able to measure our neat, our non exercise activity. Basically, you know, the twitching, the fidgeting, the small movements, you know, 200 calories there. And of course, that varies based on how much exercise we do, based on how many calories we consume, on and on and on. But let's say we measured that and we came out to 200 calories. And then we would have to account for miscellaneous things like the thermic effect of food changes in ambient temperature. You know, we went into a cold room, and then we went to a warm room, and then we stepped outside, and then we had some stressful event happened, happen. And then we also would have to consider, here in the calories outside, any energy required to break down tissue that's lost in this case due to a deficit. So we're pretending here that we've we know that there's a deficit going on of what will be 100 calories, right? Because at the top, we have 2300 calories out total, versus the 2200 consumed. And so we're going to assume that there's 100 calorie deficit. Well, in the process of breaking down tissue that requires some amount of calories. So that has to be added in here. We don't just get three 100 calories out of nowhere. We have to liberate that from our fat stores or from our muscle or wherever else. So that would also have to be considered here, obviously impossible to measure, but we would, let's say we've considered all these things. And you know, we know that we had 2300 calories out, and again, just to make it clear here, we'll get to the net changing calories in a moment. But in case it's not obvious, most people, when they're describing calories in calories out, they're making it seem as though calories in and calories out are just determined first, and then at the end, your body has a calculator, and it calculates all these things out, and it comes up, in this case, with a 100 calorie deficit. But we also need to consider that these things are all happening on a second to second momentary basis. We're constantly in a dynamic flux of fat coming out of the fat stores, fat coming in, muscle being broken down, muscle being recreated and synthesized, as well as every other tissue right? Our our skin has to be regenerated. Our red blood cells have to be regenerated. Our liver cells have to be regenerated. Everything's in a constant flux. And so if we're in a deficit in the morning, and then a surplus midday, and you know, those things are all going to affect the hormones throughout the day, which will affect our basal metabolic rate, and also will, you know, affect our needs and our eating behavior and on and on from there. So this is even here. I'm presenting it as if we kind of calculated both sides up and we came up with 100 calorie deficit, but the net change is happening on a constant basis, and it's not just today. It's affected by yesterday and last night and every moment. So these things are extremely dynamic, and it's very, very hard to try to account for any of that in a simplified equation, even as complex and we've, as we've made it here, so just wanted to mention that. But let's assume that we're, you know, our bodies are calculators. At the end of the day, we came up with 100 calorie deficit, and we, our bodies, have to make up for that somehow, right? So this 100 calorie deficit has to be coming from some liberated tissue. Now we can get 100 calories from 1/35 of a pound of body fat. That's one way. Another way is 1/5 of a pound of muscle. We'll talk about this in a second. But as I alluded to earlier, a pound of each in a weight and calories are not equivalent, and a pound of muscle actually doesn't have that many calories. It's only about 500 give or take, which will which we'll come back to, whereas a pound of body fat is much more dense, has about 3500 calories. This could also be a loss of 1/11 of a pound of skin. Nothing to say that our skin isn't, you know, some amount of skin isn't broken down to make up for the calories that we need could be bone as well. People do lose bone, especially with aging, but especially if they're not getting enough certain minerals and enough protein, enough, you know, weight bearing, movement, things like that. And so 1/9 of a pound of bone would also supply 100 calories. So these are all possibilities that could result from, you know, our. Net change of 100 calorie deficit. So let's this is, you know, a pretty in depth wave characterizing calories in, calories out. It is still not complete. There's still some important things missing here. So we're going to dig into some of those. But first we're just going to simplify a little bit, just to make it a little easier to conceptualize what we're talking about here. So if we take this equation of calories in, minus calories out, equals a net change of calories, what we're really saying is on the calories inside that this is just the potential energy in the food consumed. So in total of all the food we've consumed, and really it should go on beyond food, it's everything coming into our bodies, whether it's through our skin, whether it's through our lungs, whether it's through the food that we're eating, whether it's coming from our gut, right from the bacteria in our gut, that what we're really talking about with calories in is all of the input of potential energy. When we're talking about calories out, what we're really talking about is all of the energy that's created, right? We're taking potential energy and creating usable energy from it, like ATP we're talking about, as well as that the heat that's produced. And this is an important one, because, again, one that's not really discussed, but no physiological or no physical process is 100% efficient, which means that some energy has to be lost, typically in the form of heat. And that is absolutely the case for us humans, we actually there's a huge amount, or at least, produce a huge amount of heat in the process of creating energy. It's not wasted. We use that heat. It's important. But a huge percentage of the of the potential energy in food actually just goes to heat. And then we also need to consider the amount of potential energy excreted. This could be excreted through urine, through stool, through skin, it could be breathed out as well. So that's what we're saying when it comes to calories out, those three things, energy created, heat produced and potential energy excreted. Again, to make it clear, calories out is not just the calories burned, so to speak, which is really a meaningless statement. And if someone is saying calories out, it's just calories burned, definitely not considering everything here. And then what our net change of calories is it really just the net change of potential energy. So we had a certain amount of potential energy to start. We used it for heat energy, or we just kind of excreted it. We got rid of it. And here's the amount that's left, here's the net change. That's really all that we're saying when it comes to calories out, as we'll get at I mean, if it's not already obvious, this is not particularly meaningful, not to not particularly applicable, but this is what we get from the calories in calories out equation.

Can't really get anything more than that, and we can't simplify it a little bit further, if we wanted to kind of exemplify this, we're basically talking about the potential energy coming in. That's the calories. And so we have potential energy minus the used energy or lost energy equals potential energy left over to be stored. Or we could say the potential energy that's come in minus the used or lost energy equals potential energy to be taken from other stored potential energy. Either we have extra potential energy to store as body fat or muscle or skin or whatever it is, or we have a lack of potential energy because we didn't get enough in relative to what we used or lost. And we have to take that from our stores. We have to take it from the stores of potential energy. That's really the extent of what calories in, calories out, dictates. And this is, I would say, in kind of nearly the most complex view of it that you can have. This is the extent of our of our conclusions that we can take from it. A couple of conceptual examples that kind of illustrate how little this is telling us if you were to drink 2000 calories of gasoline in a day. And of course, it didn't kill you. You're still alive, but you drank that gasoline, and all that gasoline was then excreted, let's say just went white right there your digestive system and out the other side. And let's just say, for the sake of ease of calculation, you didn't have any metabolic processes going on, you would have had 2000 calories in, 2000 calories out, and no net change in calories, no calorie surplus, no calorie deficit, went in and out. That's the extent of what we can say from something like this, calories and calories out equation. Another example, if you ate 2000 calories in one day, and you just had a storage pouch inside where they just sat in there and they didn't do anything. You just you ate the food and it went into a load of pouch inside. You didn't have any metabolic processes going on, you would have had 2000 calories in, no calories out. So you'd have had a 2000 calorie surplus. So essentially, obviously, our bodies don't have a little pouch where they're storing their surplus, but that's kind of the idea, is that we're talking about the potential that's come in certain amount gets used or lost, and there's a certain amount left over. Now, when we consider that, it's nearly impossible to measure the amount coming in and the amount that's used or lost, this doesn't really provide as much value. All it can really say is that there was, well, all we can really say is that. If there was more potential energy coming in than was used or lost, then there was extra potential energy stored. If there was less potential energy coming in than was used or loss or lost, then there was potential energy taken from stores. That's all we can say. And that was, and that's just the net. There was a net amount taken from stores or a net amount put into storage. It's, it's really not telling us very much. It generally has to be looked at kind of backward. After some after we have some outcome. There's no way, and we'll talk about this, but there's no way that calories in, calories out, can determine what will happen. There's no it has no predictive value. It's just a way to kind of conceptualize what happened in a way that really doesn't provide much value. And we'll continue to to dig into that. And here are a few other misconceptions that I think are really important to mention right now. First is that calories are not equivalent to physiologically relevant energy. So we can have 100 calories of protein, we're actually going to assume it's just an amino acid, in this case, leucine. And the amount of energy that that can produce in terms of ATP, is about 3.8 moles. Moles moles is just a unit of measurement. It's a large number of molecules, essentially 100 calories of protein that's coming from aspartate, which is a different amino acid. So obviously the protein is comprised of many amino acids, but let's just say we had 100 calories of just aspartate, and that was converted to glucose and then used to produce energy that could produce as much as 2.2 moles of ATP. If we had 100 calories of fat that's pure palmitate, that could produce 4.7 moles of ATP, if we had 100 calories of carbohydrates from just glucose, that could provide 4.4 moles of ATP. So the amount of calories in the food doesn't say anything about the amount of ATP it can produce, because we can use different types of macronutrients more or less efficiency. Efficiently. It also doesn't say anything about the likelihood that we're going to be using any of these to produce energy versus storing it as fat. And that'll vary based on not only the macronutrient, but the type of food that it's coming with. Other polyphenols that are with it, potentially anti nutrients that are with it, other physiological or metabolic effects of the different fatty acids or of the different carbohydrates. Those things will all determine how likely it is to be used or stored. And so these are things that all would have to fit in calories and calories out somewhere, but are typically not at all considered. And that brings us to another misconception, which is that calories and weight are not equivalent, and so with that in mind, calories and tissue weight are not equivalent, we're often told that one pound of body fat equals 3500 calories. Here's where that comes from. The assumption is that there's about 85% of of the body fat is made up of triglycerides, which provides about 3450 calories, around two to 3% of the body fat is protein. So that provides 50 calories. 10% is water, so we get about 3500 calories. But that's not the case for all tissues, of course. So when we look at muscle, muscle actually only is comprised of about 500 calories, because it's about 72 73% water, some glycogen and mostly protein that's left, which is only about 20, you know, in the low 20s in terms of total percentage of composition of protein. So the idea that, you know, 3500 calorie deficit or surplus is needed for body fat, while that's still not true per se, I mean it, I guess. Okay, so I guess I'll say it this way, if you consider all the factors that we've considered so far, and some others, and you wanted to create one pound of body fat, you need to have 3500 calories worth of extra potential energy. That would be necessary, but that same amount of energy could be used to produce seven pounds of muscle. So just a massive difference here. I never hear anybody talk about but you know that, if you're you know, and by the same token, if we're talking about losing body fat versus losing muscle, if you have a 3500 calorie deficit, let's say over a week. That could be one pound of body fat, or it could be seven pounds of muscle. You could lose seven pounds of muscle or one pound of body fat, they're the exact same in terms of the caloric content there. So again, these are things that add to a lot of complication when you're trying to extrapolate out from anything within the calorie equation. This is also part of why all the calories and calories out can tell you is whether there's a net change in potential energy, but not what that changes could be muscle, could be fat, could be bone. And when you look at the amount of calories in bone, it's about 450 calories. We'll look at a few other skin comes out to about 550 again, these are all relative estimations. One pound of intestinal tissue comes out to 670 calories. And this is actually an important one. Again, speaking of things that aren't really considered. But for example, the intestinal lining of epithelium has a really rapid turnover. It's the most highly regenerative organ in the human body, and it renews its the entire amount, you know, estimations are in like four to five, four to six days, the entire epithelial lining is renewed. So. So on a daily basis, that leads to about 50 grams of renewed intestinal tissue daily. It's about 75 calories there, just for the lining of the epithelial or the epithelial lining of the intestines, when it comes to red blood cells, pound of red blood cells ends up being about 635 calories. And with white blood cells and platelets, it ends up being about 565 calories. Now, again, red blood cells and platelets also have a pretty short lifespan and are renewed quite a bit. So, you know, on a day to day basis, you could be using as much as 3030, to 50 calories on, you know, the renewal of red and white blood cells and platelets, which doesn't sound like a lot, but again, remember, if we're talking about 50 calories here or there, that could be pound of muscle, pound of body fat, whatever it is. So these are all things that all should be floating around in our minds when we're trying to think of things in terms of calories and calories out. And of course, there's also a lot of inter individual variation, where one person might maybe, because their metabolism is more turned down, they're much less likely to renew some of these tissues, whereas if someone is in a much better state metabolically, they might be renewing some of these tissues to at a much faster rate. So these things would all be quote factored into the or factored into the quote basal metabolic rate, but could fluctuate considerably. Now, another thing to consider here is that while the calories are not equal to the tissue weight, they're also not equal to the tissue weight creation. So we know that one pound of body fat is about 3500 calories, and in order to create one pound of body fat, if you had 3500 calories of fat, that would be about what you would need to produce the pound of body fat, since that body fat is mostly made up of triglycerides, and this is mostly triglycerides, so you don't really have to do anything. It just automatically. I mean, more or less, it doesn't take too much energy to convert that into, you know, break it all the way down, and then turn it back into the fat. Of course, it takes some and it's kind of hard to estimate that, but we're going to kind of forget that. But let's say we wanted to take glucose and convert that to fatty acids and then triglycerides. You know, we have to convert the glucose to the fatty acids and then to glycerol.

Well, that would require 4400 or 4471 calories of glucose to produce one pound of body fat. That's not really and again, it's really hard to kind of incorporate or consider, but that's not considering the energy required to convert the glucose to the fatty acids and to convert it to the glycer glycerol backbone, and then turn it into a pound of body fat. That's just structurally, the amount of calories of glucose it would take to basically the amount of potential energy in glucose that would be needed to convert it to a pound of body fat, the amount of potential energy in a pound of body fat in terms of converting the glucose from glucose to triglycerides, when it comes to amino acids, in this case, we'll use aspartate. It's even higher to convert the aspartate to triglycerides, enough to create one pound of body fat, it requires nearly 6000 calories. So coming back to our and we'll, we'll do this as an example here, but coming back to our net change in calories, we were saying, you know, it's kind of saying, before we'll get to this, but you could have a 3500 calorie surplus, but if that's coming from, if that's coming from triglycerides from fat, then that could be potentially an extra pound of body fat, but if it's coming from glucose, that wouldn't be enough to create a pound of body fat. So we're going to kind of apply this here, create some examples considering the differences in efficiency of ATP production, considering the differences in how many calories are comprised of each tissue, if we're breaking it down and using that in a deficit, as well as the differences in the efficiency of creating certain structures from a certain amount of calories. So if we had on our calories inside, we'll kind of skip through this quickly, because we already went through this as an example, but we had 2200 calories coming in. 2000 of those calories were absorbed, and we're going to assume we have 700 of absorbed calories of protein, and assuming that we have that we're able to produce about three moles of ATP per 100 calories of protein. This is an assumption because it would depend on the amino acids and things like that. But let's assume we would have the equivalent of about 21 moles of ATP potential from fat if we had 300 calories. So we kind of lower fat here, it would produce a potential of 14.1 moles of ATP. And if we had 1000 calories of carbs, it would produce a potential of about 44 moles of ATP. So in terms of producing energy alone, at most, we'd be able to produce about 79 moles of ATP. Let's consider this on the calories outside. So let's assume we have about 2500 total calories out. This includes everything, exercise, basal, metabolic rate, neat, all of that. We're going to assume that a percentage of of that 2500 is about 200 calories worth our excreted food. So we really only had 2300 that are available. Of that 2300 considering the efficiency of a. Production and and how well we are basically of all of our metabolic processes, we could use as much as 65% I mean, we could use more, but averages are normally around 65% of total calories that are just produced or just used for heat, basically potential energy that's just converted to heat. So we're going to assume that that leaves around 675, calories worth of need in terms of ATP, assuming that we've accounted for excretion and heat. Next thing we would need is energy. Here we're going to kind of leave it that simple. And if we know that for every one mole of ATP, it requires the equivalent of about seven calories, if we have, and this is basically the seven calories is the amount of energy equivalent in ATP, that if we're talking about 675, calories of ATP, this would be about 92 and a half moles of ATP. So we've created a deficit here in terms of, you could think of it in terms of potential energy, or in terms of our ATP needs, where we're only able to produce 79 despite the fact that we need 92 and a half. So if we consider this way, we're at a basically 13 and a half mole ATP equivalent deficit. Now it's impossible to know where we're going to get this ATP from. Are we going to produce? Are we going to break down body fat to produce this difference in ATP that we need? Are we going to break down muscle? Are we going to break down other tissues? We don't know, but let's, you know, do a couple of examples here. If we were breaking down body fat to produce ATP, this would be the equivalent of, you know, in order to produce 13 and a half moles of ATP, we would need 285 calories of fat. That'd be, point, oh, eight pounds of body fat. But if we wanted to create 13 and a half moles of ATP for muscle, this would be about 450, calories worth of protein, because the conversion of protein ATP is much less efficient. We don't produce anywhere near as much. This would be about point point eight, nine, nearly point nine pounds of muscle. So we have this small deficit here of about 300 calories, or 13 and a half moles of ATP. And we could be losing as much as point nine pounds of muscle or as little as point, oh, eight pounds of body fat. And any combination in between, right? We don't know or and again, we'll get to this. You could lose even more muscle and then gain body fat. But we'll come back to that. But the difference here just assuming it's either it's this simple and we lose just muscle or body fat. The difference here is over 1,000% it's basically an 11 times different in weight. You know, we can either lose basically nearly a pound of muscle or, point, oh, eight pounds of body fat, which is a massive, massive difference here. Now we're going to do the same thing here, but apply it in terms of a calorie surplus. So going through the same kind of order of operations, we have our calories in and same amount of protein, same amount of fat, same amount of carbs, same amount of potential. ATP 79 for the calories out, this time, we have much less calories out, only 1900 calories out. We have our assumption of 200 calories, that of the 22 that came in, the 2200 that are not absorbed. We have our assumption of 65% heat that leaves us with of all of our calories out, we need about 466 calories worth of ATP, which ends up being about 64 moles of ATP. So we have our basically surplus here of 15 moles of ATP equivalent. So of the 79 moles of ATP, 64 give or take, went to our calories out, went to our our energy expenditure. And 50, you know, 15 of those didn't get actually created. We have those as potential energy. Now it's impossible to know whether this equivalent would be left in protein, fat or carbs. We would probably assume that the most of it would be protein, because fat and carbs are more likely to be used to produce ATP relative to protein. But you know, the we would have to account for those assumptions somehow with the calories and calories out equation, which it can't so if we were to assume a few different possibilities, this could be either produced from 326, calories of fat, 348, calories of carbs, or 510, calories of protein. These are all the different places that we could be like. These are all the different surpluses that we could have, or it could be any combination of those three, it's impossible to know, then, what tissues the surplus would be used to produce. We could have 510, calories extra of protein going to muscle, or it could be going to body fat. We have, you know, same thing with carbs or fat. Those 326, calories of fat could be going toward, you know, producing, you know, to be stored as muscle or brain tissue, or whatever it is. Obviously there's a lot of conversion I would have to go on to produce muscle from it. But in any case, it's impossible to know how that surplus would be used, and we don't even know what the surplus is, which macronutrient it is, but let's assume that we were just going to be producing body fat from one of the three different macronutrients. Pounds. So if we had 326, extra calories of fat that was our surplus that could produce point 09, pounds of body fat.

If we had that 348, calories of carbs as our surplus, that would only produce 0.078, pounds of body fat. And for the protein, if we had an extra 510, calories of protein that could be used to produce, point 085, pounds of body fat. This is just assuming the number of calories and equilibrating them to the number of pounds of body fat, considering how this is also considering our estimations we had earlier of how many calories of each of each of the macronutrients would be needed to produce about a pound of body fat. So obviously, a lot of assumptions built in here. But then we could also have any combination there. But the difference here is as much as nearly 20% which is still a pretty big difference, or talking about a 20% difference in body fat gain relative to what it could be. So and again, no way to know which possibility it is, are we? Is our surplus purely of carbs, fat, protein, what tissues are being used to produce? No way to account for that in terms of calories in, calories out. All right, so let's summarize so far, as far as our calories in, calories out, issues on the calories inside, some issues we have. One is it's impossible to accurately measure the calories in even if we're wearing our food, even if we're using the nutrient label, you know, on all of the foods, it's impossible to do that accurately. Could be off by pretty significant percentages. Second is there's no way to account for the likelihood of any calories in to be converted to energy. This would, you know, affect the calories outside. Of course, there's no way to account for the efficiency of that conversion energy, are we producing more heat? Are we producing more ATP? Is it going to be the same between macronutrients, even within the same macronutrients? How different is it between different amino acids, different types of carbohydrates, different types of fats? How likely are they going to be to be converted to energy? How efficiently are they converted to energy? Those are all things that we can't really account for in terms of calories and calories out. On the calories outside, it's nearly impossible to estimate or calculate calories out, whether we're talking about the amount of food absorbed versus excreted, the amount of heat lost, our actual basal metabolic rate, which fluctuate, fluctuates constantly based on our exercise, based on our calories in the types of food, in whole food, processed food, right? We went through these studies before, hormonal state, tons of other things, even with detailed calculations, it's nearly impossible. Also, we would have to be able to account for, as I was getting at, things like metabolic adaptation, inter individual differences in absorption and excretion, differences based on the types and quantities of food consumed, then all of the extra expenditures that come into calories out, like changes in ambient temperature and stress, and even accurately measuring how many calories we used from exercise in a day, there is no really easy, accurate way to do that. So there's some issues on the calories outside, in terms of the net change in calories, there's no way for us to accurately calculate the difference between calories and calories out. So we can't even easily, or really at all, ever know the net change in calories. There's also no way to account for the likelihood that any ingested macronutrient or food or potential energy would be used to create a certain structure and then account for the difference in efficiency. So of course, as we're getting at the amount of potential energy required to produce body fat would depend on whether we're producing it from amino acids or from glucose or from fat. There's no way to account for that. There's also no way to account for the likelihood that any structure, this is, if we're in a deficit, so to speak, that any structure would be broken down to produce energy and then account for the difference in efficiency. So if we're in a quote, 500 calorie deficit, is that coming from a pound of muscle or 1/7 of a pound of fat, there's no way for us to actually know. And also, typically, when it comes to the net change in calories, this is used circularly, so kind of as an example, if you were to lose body fat, we would then say you were in a calorie deficit. But we can't use this predictively. There's no way to say that you were in a calorie deficit. So here's what would have happened. There's no way to know if you were in a calorie deficit until you saw some sort of outcome. And even then, there's no way to actually know the kind of net of what's gone on in that outcome, as well as we'll get to again. One other thing I mentioned earlier is that this is all it's not like we just have a calculator, or our bodies have a calculator, and at the end of the day, they tally everything up. They were just waiting. They had their calories out. We put down a credit card and we had our calories in. That was all of our money coming in. And now at the end of the day, we can decide how much money can we use to pay off the credit card, how much gets stored in the bank account? How much are we in debt? That doesn't happen. Everything is done on a momentary basis, right? How much energy do we need for the exercise right now? Well, if we're exercising, we're probably in a momentary calorie deficit. If we're we've just eaten, we're in a momentary calorie surplus. What determines what happens with those extra calories? Do they get stored as glycogen? Do they get stored as body fat? How much is this going to be released as glycogen or body fat later? What about muscle? You know, what's going on hormonally? So many factors that are impossible to consider in terms of calories and calories out, at least they would have to fit in here and it they aren't accounted for. There's nothing about calories and calories out that represents those or accounts for those. So to then point out another issue that we have here in terms of calories, calories calories in, calories out, when we're talking about the net change in calories, as we said, this really boils down to a net change in potential energy structure, tissue and net change. So we know at the end this is the amount extra lost, like in total that was lost in potential energy or gained in potential energy. But nothing about calories in, calories out dictates the exact structures that change, or the amounts, just the net change. All we see is like from the equation. All it tells us is the end of that balance sheet. Now again, let's forget for a moment that it's nearly impossible to measure calories in, calories out, changing calories. And let's just assume these things. So let's assume that we have 2200 calories in. Let's assume that we have 2700 calories out. So we have a 500 calorie deficit. Let's just assume that, well, this 500 calorie deficit could just be a loss of point one four pounds of body fat. That's 500 calories. So it could just be that, or the 500 calorie deficit could include a loss of 1.1 pounds of muscle as well as a gain of point one pounds of muscle. Maybe we lost one pound of muscle from our upper body, but we gained point one in our feet, our calves, our hand muscles. Maybe we lost a pound, half a pound of skin, and then we lost half a pound of bone, but then we also gained point one, four pounds of body fat. Well, if you calculate that all out, we're still at a 500 calorie deficit. All of that could fit into that 500 calorie deficit. When we say there's a 500 calorie deficit, it just tells us the net. It doesn't tell us if we lost your gain body fat. Doesn't tell us if we lost your gain muscle. We could have any combination of those things going on. We could have had less regeneration of our intestinal cells. We could have had less regeneration of our red blood cells, any number of things that could fit into that calorie deficit. So what we're getting at here is that a net change in calories alone says nothing about the gain or loss. Should say loss of body fat or muscle. That's what most people are using this calorie equation for. But the reality is that it says nothing about it. So in other words, you can be in a net calorie surplus and lose body fat as long as the net provides a gain. Maybe you've lost body fat and maybe you've gained muscle or gained other tissue. You can also gain muscle in a net calorie deficit. Maybe you've lost more total than you have gained, and so you could have gained muscle despite the fact that you're in a calorie deficit. And maybe also and maybe also lost body fat. You can also do either while being in calorie balance. So you can be in an entire calorie balance. Your net calorie balance is zero, but you've lost in calories the exact same amount in body fat as you've gained in muscle. So you've lost, let's say, 1/7 of a pound of body fat, and you've gained one pound of muscle. Let's say it's over a week. That could happen anywhere in 100% calorie balance. The you know, the calorie the net calorie change. The net change in calories says nothing about the change in tissue mass at all. So we're going to go through some takeaways here, as far as the all of the issues with calories and calories out. And then in the next episode, we'll go over an alternative that resolves a lot of these issues, doesn't have a lot of the same issues, and basically is a much, I would say, better representation, a much more helpful representation of changes in body composition and health as well, which certainly something that's missing from the calories and calories out equation. So some issues here, some some takeaways. Calories and calories out can be a way to accurately represent changes in energy, potential, energy, energy in humans over time. It can be in the way that we've described it here. It's really the only way it can be, if you're simplifying it in a way that doesn't account for these kinds of variables. It's really not going to be accurate. With that in mind, calories and calories out does not lend any support for eating less and exercising more. Nothing about this that we've described today suggests that eating less and exercising more is the solution for improving body composition, and we haven't talked about any you know how the fact that this doesn't tell us anything about our health, either nothing about calories out, calories and calories out dictates that, or suggests that, calories in calories out, is also not predictive. So there's no way to know ahead of time what's going to happen. It cannot determine an outcome ahead of time. You can't know that you're going to lose a certain amount of body fat or gain a certain amount of muscle or anything like that. You could hypothetically account for it after if after the week or after the day, you could go back and somehow find out your calories in and your calories out, you could then determine you're not changing calories, but you can't predict anything ahead of time. You can't know that, or at least in terms of body composition. Hypothetically, you could know, well, you really can't know a net change of calories, because the net change of calories also affects. Calories out. You know if, if you're building tissue, that's going to affect the calories out and then lead to less of a surplus.

So in addition, calories and calories out, cannot determine what mass is lost or gained. Have we lost muscle, lost skin, lost bone, gained any of those things. No way to account for that with calories and calories out or not. At least no way to determine that even if calories and calories out were accounted for accurately, it's nearly impossible to measure as such. It's really not something that's particularly helpful. Calories and calories out is generally reduced to completely inaccurate oversimplification. So the way that the vast majority of people regard calories and calories out is entirely inaccurate, the way that they try to apply it, the way that they act as though it is a hard truth and things like that, is generally clearly not the case. And most importantly here, calories in, calories out, does not tell us anything meaningful about how our dietary or other health choices affect our body composition. I should add in, it also doesn't tell us anything meaningful about how our dietary or other health choices affect our health. It doesn't tell us very much at all. It is a ptential way to count up what has happened, to account for what's happened, but it doesn't actually provide us much meaning or much benefit. And so that's I'm really going to wrap up with that. I know this is really in depth, very wordy, but I felt like this was kind of necessary to really get to the root of calories in, calories out, and really explain, in the deepest sense, the issues with it. And try again, try to steel man, to try to kind of provide it in a way, or expand it in a way that is most accurate, and in doing so, it really loses all all meaning. And if it's not done in that way, the meaning that it does create is just false. So I think that's really what we come to here. Now, in the next episode, in part two of this series, I'll go over an alternative framework for conceptually conceptualizing fat loss. I'll talk a bit more about why eating less and exercising more is not the best solution for fat loss. Also discuss why excess energy does not cause fat gain, and instead, it can actually lead to fat loss. So we'll get into that a little bit, and I'll also discuss how you can get stuck in the cycle of weight gain under eating and constant hunger, which are all directly interrelated, and how to get out of that cycle. If you did enjoy today's episode, please leave a like or comment, if you're watching on YouTube, if you're listening else or elsewhere, please leave a review or five star rating on iTunes. All of those things really do a lot to help support the podcast, and are very much appreciated. To check out the show notes for today's episode, where I'll link to the studies and articles and anything else that I referenced today. You can head over to Jay Feldman wellness.com/podcast and if you are looking to lose weight and you're looking for practical strategies to help you do so without simply cutting calories, or if you're looking to optimally support your metabolism, improve your digestion, get amazing sleep, rebalance your hormones, boost your energy and so much more with clear action steps and strategies along with personalized guidance from me, head over to Jay Feldman wellness.com/solution where you can find all the information for the energy balance Solution Program. This program includes customized health coaching. It also includes a video library, including a video specifically with strategies for how you can lose weight without destroying your metabolism, as well as videos on restoring gut health, regulating blood sugar, boosting your metabolism, getting amazing, restorative sleep, rebalancing hormones and tons more. It also includes resources like a sample meal plan, recipes and a supplement guide, as well as a private community so head over to Jay Feldman wellness.com/solution, to check out all the details, and with that, I'll see you on the next episode.