5 ms·

> “Calorie is a calorie” is thermodynamically correct, but not true when it comes to diet. It’s like saying “it doesn’t matter if you drink booze or beer as lon

> “Calorie is a calorie” is thermodynamically correct, but not true when it comes to diet. It’s like saying “it doesn’t matter if you drink booze or beer as long as you get the same amount of alcohol”. Alcohol intake is much easier to regulate with mild beverages. The same applies to energy intake with low-glycemic-index products. While I have serious concerns about most nutritional/exercise studies the underwhelming number that point to low carb/low fat/etc. as the end-all-be-all even controlled for calories is still mind-blowing. It's all calories at the end of the day, you should do whatever satisfies your micro and macro needs while helping you to stick to the diet.

ravenstine 3y ago
I think we would both agree that a theoretically imperfect diet that improves health is preferable to a perfect diet that doesn't maintain health in practice. However, it's not "all calories" at the end of the day. If all we cared about was losing or maintaining weight, then calories might approach being a tool for it. Yet it's not actually the weight we care about when we say we want to lose weight; it's the body fat we care about, and probably muscle maintenance, which is why CICO falls apart. Diets composed of different macro ratios can have drastically different outcomes, and what's funny about that is most camps ranging from vegans to carnivores implicitly agree on this, yet many still choose to elevate theoretical physics above physiology. A lump of coal has measurable "calories" when burned in a bomb calorimeter. That doesn't mean that a human will oxidize a lump of coal and produce calories. A human can eat carbs or fat, but they result in different outcomes because those things are fundamentally metabolized and utilized differently. Even different types of carbs and different types of fat have different effects from each other, regardless of caloric value. In terms of a person's health status, calories are hardly relevant. Also, most people don't even come close to measuring their "calories." When they lose weight counting calories, they are getting lucky by figuring out how much it takes to under eat, which can also mean unnecessary muscle loss when they don't take into account the composition of what they are eating. Many people who count calories either struggle to lose that weight or lose a ton of muscle because they believe that a calorie is a calorie and that therefore they can eat crap and "run it off." In either case, they're not really measuring what they think they're measuring because calorie counts on food are allowed to be as far off as 20%, and virtually nobody weighs their feces to estimate how many consumed "calories" didn't actually get used.
- JohnMakin 3y ago
  When you're at a caloric deficit your body will begin to burn fat. It doesn't make a difference what kind of calories you're intaking - your body literally does not know. What you're speaking to wrt fat loss vs weight loss is a much more complicated subject than just eating the right foods and having a calorie deficit.
  - ravenstine 3y ago
    There's no "caloric deficit." Your body stores and oxidizes fat because it needs to get the appropriate mass from somewhere. If the body has fat to oxidize, then there's no deficit of anything. > It doesn't make a difference what kind of calories you're intaking - your body literally does not know. You're conflating a few things here. Fundamentally, you're saying that the body doesn't contain an internal calorie counter. In that sense, you are absolutely correct. The human body, and pretty much all organisms performing respiration, does not keep track of calories in any capacity or measure mass. The only thing the body can do is delegate different kinds of mass to the places in different cells where their presence would be of benefit to the survival of the system. That's really it, though it's a bit of an oversimplification. However, if we correct "kind of calories" to "kind of mass", and drop the whole idea of the body "knowing" something, then what you are saying is fundamentally untrue. It is not controversial in any way that the cells in the human body, and all creatures for that matter, treat macronutrients differently and prioritize them in ways that are not equivalent. Yes, it's more complicated, but food composition is way up there in terms of importance.
  - vlod 3y ago
    >When you're at a caloric deficit your body will begin to burn fat. It doesn't make a difference what kind of calories you're intaking Of course it matters. Here's an experiment. Drink only 12 cans of soda (~140 cals each) spread over the day (so 1680 cals total). Assuming a BMR of 2000 cals (standard male), you're at a deficit. Assuming you start drinking as soon as you get up and last one just before you got to sleep, will you lose weight? No.. because your insulin is constantly spiked throughout the day which inhibits fat burn. Now try it with broccoli (or even just fat).
JohnMakin 3y ago
Came here to say this. There was a pretty funny study some researcher did a long time ago where he ate nothing but twinkies and water for a month and lost a ton of weight by restricting calories. Was he probably miserable and hungry? Sure. But, your body doesn't really differentiate too much when it comes to calories in vs calories out. Proteins/Fiber/etc. are only good diet options because they are very filling for the amount of calories they have. Additionally, certain macros like protein help to build muscle, which can raise your TDEE (total daily energy expenditure). But you're right, a calorie definitely is a calorie - even in a diet.
- ravenstine 3y ago
  I found articles about this experiment, but it doesn't appear that an actual study was performed or formal paper published about it. Although that person was (perhaps still is) a professor in nutrition, this Twinkie story remains an anecdote. Anecdotes are worth something, but what that means is we're missing a bunch of variables, especially what he was eating prior to the experiment and whether eating nothing but Twinkies and other snack foods also lead to muscle loss. It's also totally unclear, from what I'm reading, how much exercise he was performing and what is TDEE was prior to and after the weight loss. A month is not a lot of time to understand the long term sustainability of a diet like that. If a person finds that a Twinkie diet works to help them cut fat in a short period of time, there's really not much to object to. Asserting that it's OK to just eat food that is classically categorized as "junk" as long as you don't eat too many calories is fallacious and ignores the poisonous nature of the things we eat. > But you're right, a calorie definitely is a calorie - even in a diet. It's not that calories aren't what they are, or that they don't have some use. The core objection is that they aren't an appropriate measure for human health. At best, they are a very imperfect proxy for mass measurement. If you want to lose weight, don't eat more anhydrous mass than you eliminate. When you measure calories to the exclusion of nutrient composition, not only is one ignoring a mode of optimization (that could lead to longer term successful outcomes), but they are relying on very inaccurate tools. Calorie counts on packaging are allowed to be as inaccurate as 20%, and the tools people use to count their "calories" really aren't accurate enough for that purpose (researchers still use respiratory gas analysis for that reason). Obviously, someone can maintain or lose weight by counting "calories." That does not mean what they are doing is optimal or sustainable in the long term, or that anyone is a fool for taking the exact opposite approach. The many people out there who do not count calories, eat as much as they want of a specific diet, incidentally eat more in "calories", and still lose weight throw a wrench into the whole "it's just calories in, calories out" hypothesis.
InSteady 3y ago
Furthermore, "a calorie is a calorie" ignores the incredibly complex relationships in our microbiome between bacteria, fungi, and yes even viruses (which apparently can and do absorb nutrients when they are in a host cell), that constitute a significant portion of the metabolism going on in our bodies. Dietary changes can alter the microbiome dramatically in relatively short periods of time, with some studies showing measurable microbiome composition shifts in as little as 3 weeks! [0] (note that while most of the examples in this review are on mice, there are human studies included further down that also demonstrate this rapid shift) Processed carbs, and especially refined sugar, is rapidly absorbed in the upper GI, bypassing most of the beneficial microbes that 'preprocess' much of our raw food intake (especially complex carbs, like the prebiotic fibers and such) into more beneficial metabolites. Including bacterial metabolites that are essential to health and cellular energy. Consider processed fructose vs fructose from a fruit, eaten whole. The former starts entering the bloodstream directly upon consumption, where it then must be processed by our own liver at some metabolic expense. Some people refer to fructose as "toxic" for reasons such as this: >fructose induces a number of proinflammatory, fibrogenic, and oncogenic signaling pathways that explain its deleterious effects in the body, especially in the liver. [1] Furthermore, when there is excess free fructose in the upper intestines, more than the body can rapidly absorb, it is also metabolically expensive simply to clear it from the gut to get it into the liver. This process can lead to ATP depletion in the GI tract. [1] Thus it robs us of that magical substance that powers all of our cellular activity, from muscle firing to nerve impulse activation (both of which are critical to optimum digestive function) and beyond. On the other hand, when fructose is bound up in in complex carbs (fruit), it gets farther down into the intestines where fructose loving bacteria such as F. prausnitzi can ferment it for us. [2] In addition to sparing our ATP reserves in the gut and sparing our liver the trouble of processing fructose, F. prausnitzi produces an incredibly beneficial nutrient, butyrate, in the process. Butyrate has protective effects on the gut and intestinal barrier, and it is also a key building block of that lovely neurotransmitter GABA, that helps keep all of our other neurotransmitters in check (which is why it is called the "calming neurotransmitter"). Finally, on a hunch, I went ahead and googled "butyrate and satiety" which immediately returned this: > Fermentation of fiber in the gut generates short-chain fatty acids (SCFA), such as butyrate, which decrease food intake and promote weight loss in rodent models. SCFA have been shown to enhance secretion of the gut satiety hormone peptide YY (PYY). [3] Further investigation shows that this peptide is also active in humans, reducing hunger signals in the brain. [4] All of this is to say, while the popular phrase "a calorie is a calorie" can help people to understand diet and weight loss in terms of an energy budget, the reality is far, far more complex than that. And we have truly only scratched the surface of all the complexity going on in the microbiome as it relates to diet and cellular functions throughout the body. Especially our immune system, which appears to borrow many critical metabolites from bacterial activity on the foods we choose to eat. It will be exciting to see how far down this rabbit hole we get in the coming years. For now, whenever we hear "a calorie is a calorie," it is useful to remember that things are not nearly so simple, and this sometimes helpful simplification can lead us astray quickly if we are not judicious in how we apply it. [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8398149/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8398149/ [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8267750/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8267750/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7697676/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7697676/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6818935/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6818935/ [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516703 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516703

ravenstine 3y ago

I think we would both agree that a theoretically imperfect diet that improves health is preferable to a perfect diet that doesn't maintain health in practice. However, it's not "all calories" at the end of the day. If all we cared about was losing or maintaining weight, then calories might approach being a tool for it. Yet it's not actually the weight we care about when we say we want to lose weight; it's the body fat we care about, and probably muscle maintenance, which is why CICO falls apart. Diets composed of different macro ratios can have drastically different outcomes, and what's funny about that is most camps ranging from vegans to carnivores implicitly agree on this, yet many still choose to elevate theoretical physics above physiology. A lump of coal has measurable "calories" when burned in a bomb calorimeter. That doesn't mean that a human will oxidize a lump of coal and produce calories. A human can eat carbs or fat, but they result in different outcomes because those things are fundamentally metabolized and utilized differently. Even different types of carbs and different types of fat have different effects from each other, regardless of caloric value. In terms of a person's health status, calories are hardly relevant. Also, most people don't even come close to measuring their "calories." When they lose weight counting calories, they are getting lucky by figuring out how much it takes to under eat, which can also mean unnecessary muscle loss when they don't take into account the composition of what they are eating. Many people who count calories either struggle to lose that weight or lose a ton of muscle because they believe that a calorie is a calorie and that therefore they can eat crap and "run it off." In either case, they're not really measuring what they think they're measuring because calorie counts on food are allowed to be as far off as 20%, and virtually nobody weighs their feces to estimate how many consumed "calories" didn't actually get used.

JohnMakin 3y ago
When you're at a caloric deficit your body will begin to burn fat. It doesn't make a difference what kind of calories you're intaking - your body literally does not know. What you're speaking to wrt fat loss vs weight loss is a much more complicated subject than just eating the right foods and having a calorie deficit.
- ravenstine 3y ago
  There's no "caloric deficit." Your body stores and oxidizes fat because it needs to get the appropriate mass from somewhere. If the body has fat to oxidize, then there's no deficit of anything. > It doesn't make a difference what kind of calories you're intaking - your body literally does not know. You're conflating a few things here. Fundamentally, you're saying that the body doesn't contain an internal calorie counter. In that sense, you are absolutely correct. The human body, and pretty much all organisms performing respiration, does not keep track of calories in any capacity or measure mass. The only thing the body can do is delegate different kinds of mass to the places in different cells where their presence would be of benefit to the survival of the system. That's really it, though it's a bit of an oversimplification. However, if we correct "kind of calories" to "kind of mass", and drop the whole idea of the body "knowing" something, then what you are saying is fundamentally untrue. It is not controversial in any way that the cells in the human body, and all creatures for that matter, treat macronutrients differently and prioritize them in ways that are not equivalent. Yes, it's more complicated, but food composition is way up there in terms of importance.
- vlod 3y ago
  >When you're at a caloric deficit your body will begin to burn fat. It doesn't make a difference what kind of calories you're intaking Of course it matters. Here's an experiment. Drink only 12 cans of soda (~140 cals each) spread over the day (so 1680 cals total). Assuming a BMR of 2000 cals (standard male), you're at a deficit. Assuming you start drinking as soon as you get up and last one just before you got to sleep, will you lose weight? No.. because your insulin is constantly spiked throughout the day which inhibits fat burn. Now try it with broccoli (or even just fat).

JohnMakin 3y ago

Came here to say this. There was a pretty funny study some researcher did a long time ago where he ate nothing but twinkies and water for a month and lost a ton of weight by restricting calories. Was he probably miserable and hungry? Sure. But, your body doesn't really differentiate too much when it comes to calories in vs calories out. Proteins/Fiber/etc. are only good diet options because they are very filling for the amount of calories they have. Additionally, certain macros like protein help to build muscle, which can raise your TDEE (total daily energy expenditure). But you're right, a calorie definitely is a calorie - even in a diet.

ravenstine 3y ago
I found articles about this experiment, but it doesn't appear that an actual study was performed or formal paper published about it. Although that person was (perhaps still is) a professor in nutrition, this Twinkie story remains an anecdote. Anecdotes are worth something, but what that means is we're missing a bunch of variables, especially what he was eating prior to the experiment and whether eating nothing but Twinkies and other snack foods also lead to muscle loss. It's also totally unclear, from what I'm reading, how much exercise he was performing and what is TDEE was prior to and after the weight loss. A month is not a lot of time to understand the long term sustainability of a diet like that. If a person finds that a Twinkie diet works to help them cut fat in a short period of time, there's really not much to object to. Asserting that it's OK to just eat food that is classically categorized as "junk" as long as you don't eat too many calories is fallacious and ignores the poisonous nature of the things we eat. > But you're right, a calorie definitely is a calorie - even in a diet. It's not that calories aren't what they are, or that they don't have some use. The core objection is that they aren't an appropriate measure for human health. At best, they are a very imperfect proxy for mass measurement. If you want to lose weight, don't eat more anhydrous mass than you eliminate. When you measure calories to the exclusion of nutrient composition, not only is one ignoring a mode of optimization (that could lead to longer term successful outcomes), but they are relying on very inaccurate tools. Calorie counts on packaging are allowed to be as inaccurate as 20%, and the tools people use to count their "calories" really aren't accurate enough for that purpose (researchers still use respiratory gas analysis for that reason). Obviously, someone can maintain or lose weight by counting "calories." That does not mean what they are doing is optimal or sustainable in the long term, or that anyone is a fool for taking the exact opposite approach. The many people out there who do not count calories, eat as much as they want of a specific diet, incidentally eat more in "calories", and still lose weight throw a wrench into the whole "it's just calories in, calories out" hypothesis.

InSteady 3y ago

Furthermore, "a calorie is a calorie" ignores the incredibly complex relationships in our microbiome between bacteria, fungi, and yes even viruses (which apparently can and do absorb nutrients when they are in a host cell), that constitute a significant portion of the metabolism going on in our bodies. Dietary changes can alter the microbiome dramatically in relatively short periods of time, with some studies showing measurable microbiome composition shifts in as little as 3 weeks! [0] (note that while most of the examples in this review are on mice, there are human studies included further down that also demonstrate this rapid shift) Processed carbs, and especially refined sugar, is rapidly absorbed in the upper GI, bypassing most of the beneficial microbes that 'preprocess' much of our raw food intake (especially complex carbs, like the prebiotic fibers and such) into more beneficial metabolites. Including bacterial metabolites that are essential to health and cellular energy. Consider processed fructose vs fructose from a fruit, eaten whole. The former starts entering the bloodstream directly upon consumption, where it then must be processed by our own liver at some metabolic expense. Some people refer to fructose as "toxic" for reasons such as this: >fructose induces a number of proinflammatory, fibrogenic, and oncogenic signaling pathways that explain its deleterious effects in the body, especially in the liver. [1] Furthermore, when there is excess free fructose in the upper intestines, more than the body can rapidly absorb, it is also metabolically expensive simply to clear it from the gut to get it into the liver. This process can lead to ATP depletion in the GI tract. [1] Thus it robs us of that magical substance that powers all of our cellular activity, from muscle firing to nerve impulse activation (both of which are critical to optimum digestive function) and beyond. On the other hand, when fructose is bound up in in complex carbs (fruit), it gets farther down into the intestines where fructose loving bacteria such as F. prausnitzi can ferment it for us. [2] In addition to sparing our ATP reserves in the gut and sparing our liver the trouble of processing fructose, F. prausnitzi produces an incredibly beneficial nutrient, butyrate, in the process. Butyrate has protective effects on the gut and intestinal barrier, and it is also a key building block of that lovely neurotransmitter GABA, that helps keep all of our other neurotransmitters in check (which is why it is called the "calming neurotransmitter"). Finally, on a hunch, I went ahead and googled "butyrate and satiety" which immediately returned this: > Fermentation of fiber in the gut generates short-chain fatty acids (SCFA), such as butyrate, which decrease food intake and promote weight loss in rodent models. SCFA have been shown to enhance secretion of the gut satiety hormone peptide YY (PYY). [3] Further investigation shows that this peptide is also active in humans, reducing hunger signals in the brain. [4] All of this is to say, while the popular phrase "a calorie is a calorie" can help people to understand diet and weight loss in terms of an energy budget, the reality is far, far more complex than that. And we have truly only scratched the surface of all the complexity going on in the microbiome as it relates to diet and cellular functions throughout the body. Especially our immune system, which appears to borrow many critical metabolites from bacterial activity on the foods we choose to eat. It will be exciting to see how far down this rabbit hole we get in the coming years. For now, whenever we hear "a calorie is a calorie," it is useful to remember that things are not nearly so simple, and this sometimes helpful simplification can lead us astray quickly if we are not judicious in how we apply it. [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8398149/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8398149/ [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8267750/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8267750/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7697676/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7697676/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6818935/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6818935/ [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516703 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516703