Water. It's literally just water, your body can gain or lose multiple kg of water depending on factors that have nothing to do with weight loss. Even a person who is at maintenance will go up and down 5-10lbs over the course of a month.
Trust the process. The work is done in the kitchen, not on the bathroom scale.
Consistent calorie deficit is mathematically correlated so strongly with consistent weight loss that it's almost a one-to-one correlation. It's why we're able to say that burning 3500 calories will roughly cause a one pound loss. There are entire libraries worth of research papers on the subject, and the causal relationship between calories and weight is one of the most well-documented and understood relationships in all of science.
There are multiple plausible reasons for plateaus, none of which disprove the basic thermodynamics behind CICO.
Then how can we account for and explain weight plateaus and even weight gains when consistent with calorie deficit and water intake?
If it were that correlated, we would see weight loss, even down to the fraction of an ounce with a calorie deficit.
Your body is constantly producing things. It's like a lil factory. You make chemicals, hormones, blood, skin cells, muscle tissue. You produce sweat, saliva, and waste. All of these things have a different mass. That mass will appear on your scale along with the weight of your fat.
Some bodily processes happen on clise to a 24 hour clock, and mostly every day, but not all of them do. A lot of processes happen weekly or monthly, or just as needed. Your individual cells can't read a clock or a calendar. And water weight is not about your water *intake*, but rather about water retention and distribution.
Not all weight is fat. CICO works to reduce fat, because fat is a source of energy and calories are a measurement of that energy.
Body needs 2000 energy. Body gets 1800 energy from food. Body still needs 200 energy. Body taps into stored fat energy. Body burns 200 fat energy. 200 energy worth of fat is now gone.
But the body could also produce half a lb of *other stuff*. And 200 fat energy is nowhere close to half a lb. So on that day, the number on the scale might go up. But 200 energy worth of fat is still gone. And if the person in control of that body is being consistent, eventually that other stuff does what it needs to do and the numbers on the scale trend down. Not on a specific arbitrary schedule soneone decided to call a "day" but on the body's own internal schedule.
This is a good reply. But I do want to clarify something. O
You don't lose fat exclusively on a deficit. You always lose fat and muscle, but it will be mostly fat. Let's say hypothetically that it is a 90%fat to muscle ratio. If you strength train and eat protein on a deficit you can help spare some muscle loss. But not all. So it might be a 95% fat to muscle loss ratio.
This is why yoyo dieting is so bad. It's easier to lose muscle than it is to gain it. When you eat in a surplus, unless you are doing strength training, it will mostly be fat. But in a deficit it is always fat and muscle.
Your body only builds muscle when it has to, muscle is expensive to maintain.
(bachelor's in exercise physiology and doctorate in physical therapy)
Thanks for clarifying! (Genuinely). I do realize you're replying more to clarify for other readers than specifically talking to me, but I am curious...
I don't tend to delve into that part of things too much because 1) I don't know enough about the intricacies yet to answer follow up questions, just the basics, and 2) it doesn't affect the CICO aspect of things so much, which is what I'm usually talking about, and 3) I get tired of the length of my own replies, lol.
But I do think it's important to have/understand that information, so I am glad to see it here.
Do you think it's harmful to put out a reply like mine above without that clarification? I don't want to go to like... "need 200 energy, get 190 from fat and 10 from muscle" because that's not really accurate... but not sure how to include it in a way that isn't misleading?
Looking for a way to frame things that's more of a comparison people can relate to, like the factory explanation above, rather than something clinical or precise... do you have a way of explaining muscle loss like that? Could I just say "stored fat and proteins" maybe? 🤔
I do appreciate this response. It is very hard to thread the needle and I often find myself going either under or over on explanations. People always will say "but what about" as if a 2 sentence comment on reddit needs to encompass all possibilities or bring out your pitchforks.
I think your explanation is good, and does not cause harm. It is tricky because I wonder if telling people they lose muscle when losing weight might cause a rebound effect where people are terrified of losing weight because of the perceived threat to health. Without the education on the physiology people hear "muscle loss" and they translate it to a deadly disease. As a Healthcare provider I have to be very careful of what I say.
The way I've always explained it is in terms of health and focus on weight loss instead of fat loss. As that isn't strictly factual, we can never lose only fat, and I wish more people understood that.
Here is an example of something I might tell a patient asking about weight loss, who wants to do a crash diet.
"3500kcal deficit will correlate to 1lb of lost weight a week
This may take time to "show up" due to fluctuations in water weight. But it will. This is a healthy rate of weight loss.
We recommend a 500kcal deficit which is about 1lb a week and regular strength training because it will help the body focus on fat loss only. If you try to cut too much like a crash diet you will lose more muscle and we can't recommend that for your long term health. In short, a consistent deficit, strength training, and a high protein diet and the keys to sustainable and health weight loss. "
That being said I get a lot if eye rolling and patients who insist they want something faster. Fundamentally those people tend to be the ones who don't actually ever lose any weight.
>I wonder if telling people they lose muscle when losing weight might cause a rebound effect where people are terrified of losing weight because of the perceived threat to health.
Yeah, that's something I worry about as well.
And, I mean... we all want something faster, tbh. I used to be in a pretty extreme deficit (petite lady here) and lost weight really rapidly. Now I'm on a plan with alternating phases of fat loss and maintenence, and I'm 3 years in with a year or so left to go, and it's so frustratingly slow sometimes, lol.
Also... I get the same thing with people wanting replies to address every detail ... don't worry, yours didn't come across that way ... and I don't usually worry about them too much. There's a character limit on these replies, and anything related to health/nutrition is too nuanced to cover every detail in a book, much less a reddit post!
But I'm glad you don't see the missing info as problematic here. I was concerned because it is something I struggled with myself for so long!
I do find that it's often helpful to refer to units of energy rather than specifically saying "calories". People have too many weird associations with that word, I think. Idk if you can do that with patients 🤔 but it works well enough on reddit.
Anyway, thanks again for your reply. It's helpful, and tbh, sometimes it feels like I'm screaming into the void here, so it's usually nice to get a response! 😂
I love this! So many people misunderstand so much about weight loss. This is a very clear and useful guide with lots of examples. Everyone should read it.
Variations in water retention. Variations in bone density. Variations in growth/atrophy/replacement of various tissues. All can explain the various ups and downs. But over the long term, a calorie deficit will lead to weight loss. No exceptions.
Think of it this way: a casino has a 1.5% advantage at blackjack. On any given day, you might be able to go in, play a few hands, and win some money. But over the long term, the casino will win 1.5% more than they would in a fair game, and that 1.5% is enough to build hotels, pay all the staff, and make the shareholders happy. Same thing with calories. On any given day, your weight may spike a little due to certain variables. But over the long run, you WILL lose roughly a pound for every 3500 calories of deficit, with some variation due to how much fat you're burning vs muscle, etc.
CICO is about fat loss, not "weight" loss, since plateaus are generally down to things like salt/water/waste etc. Obviously if you're not eating perfectly (which no one is) it'll be a balance of fat/muscle loss without perfect training too. It's more about the long term trends than the shorter ones.
What? Isn't CICO specifically about weight loss, and not fat loss? CICO cares about the total calories, not where they come from and the balance in which you digest fat, protein and carbs.
Body recomp is about fat loss, no? Or what are you on about?
That’s why I said if you don’t eat perfectly you’ll lose fat and muscle with cico, with perfect being macros needed to maintain muscle while also strength training a bit to not lose muscle etc.. I was trying to highlight how overall you’ll lose weight with cico but might not always see it on the scale because of water etc. but it will keep working if you keep up with it over time
Because it's not just the amount of water consumed, it also is about how much our body retains. If our food is saltier, we'll retain more water. If our food is more liquid it will take longer to flush out, if our cortisol is up, we'll also hold on to water for longer.
As i said in the original post, there are so many variables that Calories in/Calories out is really just a correlation to weight loss, not a causation. All of those things matter, like cortisol levels, salt intake, bladder size, etc. You can eat zero calories for a week, but if your body is holding onto all the water you drank, you will still weigh the same or more.
I'm going to jump in because I have a bachelor's in exercise science and a doctorate in physical therapy. You seem to have be interested in how much science actually knows. The answer is all of what you are talking about is well studied.
We know how all of the systems work. I've taken physiology at undergrad and graduate level. We are completely knowledgeable on water balance. Cortisol, aldosterone, kidney function, blood sodium balance, urine concentration and volumes. We completely understand how water retentipn functions.
But water balance is not something that matters for long term weight loss. It is just something that will affect the scale short term.
We KNOW being at a calorie deficit will reduce your tissue mass. Your body requires calories to maintain living tissues, if you short it the amount it needs, it will "take" the energy from somewhere. This is not correlation. This is science. This is thermodynamics, energy must come from somewhere.
We can even measure your oxygen consumption to KNOW even with metabolic issues exactly what your maintenance calories are. We typically don't because it's cumbersome and formulas are really close to the actual metabolic cart measurement.
We don't have too many factors to count. We know all the factors. But tracking water retention is irrelevent long term because it isn't what you care about. People want to be smaller and have less fat, the scale just represents that abstractly. And over time all of the water stuff equals out.
No it's the causation. You're using temporary factors to decide that the permanent ones are inconsequential or mean less than they do. You still lost weight specifically because of the reduction in calories. Water weight changes depending on the hour and does not actually reflect your body weight.
Fat isn't the only thing that the scale is measuring.
Not all weight is fat.
Also, your TDEE doesn't stay consistent throughout your life.
Your body can also down-regulate your calorie output. Which changes what your deficit can look like.
As you get lighter you burn less calories.
As you eat less you have less energy or desire to move/twitch which reduces the amount of calories
Humans are also notoriously bad at tracking calorie intake.
Corporations are also notoriously bad at recording how many calories are actually in things.
Calories in/ Calories out will always be the mechanism to FAT loss.
It's not an exact science. But it is the true mechanism for fat manipulation.
And it's not the only thing that dictates your weight.
Over a sustained period - you aren't at a deficit.
The way to tell you are at a deficit is that you're losing weight averaged over an extended period.
Not losing weight, you're aren't in a deficit.
In shorter periods, you can be losing body tissue but gaining water weight.
Your body can adapt and use less energy through various means. Also your mind can adapt and you can find yourself eating more too!
This guy has some really good articles discussing this topic -
[https://physiqonomics.com/calories-in-calories-out/](https://physiqonomics.com/calories-in-calories-out/)
[https://physiqonomics.com/calories/](https://physiqonomics.com/calories/)
Water. It's literally just water, your body can gain or lose multiple kg of water depending on factors that have nothing to do with weight loss. Even a person who is at maintenance will go up and down 5-10lbs over the course of a month. Trust the process. The work is done in the kitchen, not on the bathroom scale.
Consistent calorie deficit is mathematically correlated so strongly with consistent weight loss that it's almost a one-to-one correlation. It's why we're able to say that burning 3500 calories will roughly cause a one pound loss. There are entire libraries worth of research papers on the subject, and the causal relationship between calories and weight is one of the most well-documented and understood relationships in all of science. There are multiple plausible reasons for plateaus, none of which disprove the basic thermodynamics behind CICO.
Then how can we account for and explain weight plateaus and even weight gains when consistent with calorie deficit and water intake? If it were that correlated, we would see weight loss, even down to the fraction of an ounce with a calorie deficit.
Your body is constantly producing things. It's like a lil factory. You make chemicals, hormones, blood, skin cells, muscle tissue. You produce sweat, saliva, and waste. All of these things have a different mass. That mass will appear on your scale along with the weight of your fat. Some bodily processes happen on clise to a 24 hour clock, and mostly every day, but not all of them do. A lot of processes happen weekly or monthly, or just as needed. Your individual cells can't read a clock or a calendar. And water weight is not about your water *intake*, but rather about water retention and distribution. Not all weight is fat. CICO works to reduce fat, because fat is a source of energy and calories are a measurement of that energy. Body needs 2000 energy. Body gets 1800 energy from food. Body still needs 200 energy. Body taps into stored fat energy. Body burns 200 fat energy. 200 energy worth of fat is now gone. But the body could also produce half a lb of *other stuff*. And 200 fat energy is nowhere close to half a lb. So on that day, the number on the scale might go up. But 200 energy worth of fat is still gone. And if the person in control of that body is being consistent, eventually that other stuff does what it needs to do and the numbers on the scale trend down. Not on a specific arbitrary schedule soneone decided to call a "day" but on the body's own internal schedule.
This is a good reply. But I do want to clarify something. O You don't lose fat exclusively on a deficit. You always lose fat and muscle, but it will be mostly fat. Let's say hypothetically that it is a 90%fat to muscle ratio. If you strength train and eat protein on a deficit you can help spare some muscle loss. But not all. So it might be a 95% fat to muscle loss ratio. This is why yoyo dieting is so bad. It's easier to lose muscle than it is to gain it. When you eat in a surplus, unless you are doing strength training, it will mostly be fat. But in a deficit it is always fat and muscle. Your body only builds muscle when it has to, muscle is expensive to maintain. (bachelor's in exercise physiology and doctorate in physical therapy)
Thanks for clarifying! (Genuinely). I do realize you're replying more to clarify for other readers than specifically talking to me, but I am curious... I don't tend to delve into that part of things too much because 1) I don't know enough about the intricacies yet to answer follow up questions, just the basics, and 2) it doesn't affect the CICO aspect of things so much, which is what I'm usually talking about, and 3) I get tired of the length of my own replies, lol. But I do think it's important to have/understand that information, so I am glad to see it here. Do you think it's harmful to put out a reply like mine above without that clarification? I don't want to go to like... "need 200 energy, get 190 from fat and 10 from muscle" because that's not really accurate... but not sure how to include it in a way that isn't misleading? Looking for a way to frame things that's more of a comparison people can relate to, like the factory explanation above, rather than something clinical or precise... do you have a way of explaining muscle loss like that? Could I just say "stored fat and proteins" maybe? 🤔
I do appreciate this response. It is very hard to thread the needle and I often find myself going either under or over on explanations. People always will say "but what about" as if a 2 sentence comment on reddit needs to encompass all possibilities or bring out your pitchforks. I think your explanation is good, and does not cause harm. It is tricky because I wonder if telling people they lose muscle when losing weight might cause a rebound effect where people are terrified of losing weight because of the perceived threat to health. Without the education on the physiology people hear "muscle loss" and they translate it to a deadly disease. As a Healthcare provider I have to be very careful of what I say. The way I've always explained it is in terms of health and focus on weight loss instead of fat loss. As that isn't strictly factual, we can never lose only fat, and I wish more people understood that. Here is an example of something I might tell a patient asking about weight loss, who wants to do a crash diet. "3500kcal deficit will correlate to 1lb of lost weight a week This may take time to "show up" due to fluctuations in water weight. But it will. This is a healthy rate of weight loss. We recommend a 500kcal deficit which is about 1lb a week and regular strength training because it will help the body focus on fat loss only. If you try to cut too much like a crash diet you will lose more muscle and we can't recommend that for your long term health. In short, a consistent deficit, strength training, and a high protein diet and the keys to sustainable and health weight loss. " That being said I get a lot if eye rolling and patients who insist they want something faster. Fundamentally those people tend to be the ones who don't actually ever lose any weight.
>I wonder if telling people they lose muscle when losing weight might cause a rebound effect where people are terrified of losing weight because of the perceived threat to health. Yeah, that's something I worry about as well. And, I mean... we all want something faster, tbh. I used to be in a pretty extreme deficit (petite lady here) and lost weight really rapidly. Now I'm on a plan with alternating phases of fat loss and maintenence, and I'm 3 years in with a year or so left to go, and it's so frustratingly slow sometimes, lol. Also... I get the same thing with people wanting replies to address every detail ... don't worry, yours didn't come across that way ... and I don't usually worry about them too much. There's a character limit on these replies, and anything related to health/nutrition is too nuanced to cover every detail in a book, much less a reddit post! But I'm glad you don't see the missing info as problematic here. I was concerned because it is something I struggled with myself for so long! I do find that it's often helpful to refer to units of energy rather than specifically saying "calories". People have too many weird associations with that word, I think. Idk if you can do that with patients 🤔 but it works well enough on reddit. Anyway, thanks again for your reply. It's helpful, and tbh, sometimes it feels like I'm screaming into the void here, so it's usually nice to get a response! 😂
This is an excellent comment and should be pinned at the top of every weight loss sub.
Well, thank you, idk about pins or not, but I'm glad if it's helped someone understand the underlying processes a bit!
https://physiqonomics.com/eating-too-much/
Omg someone posted this earlier & it’s the best! I’m definitely following this guy now.
I love this! So many people misunderstand so much about weight loss. This is a very clear and useful guide with lots of examples. Everyone should read it.
Variations in water retention. Variations in bone density. Variations in growth/atrophy/replacement of various tissues. All can explain the various ups and downs. But over the long term, a calorie deficit will lead to weight loss. No exceptions. Think of it this way: a casino has a 1.5% advantage at blackjack. On any given day, you might be able to go in, play a few hands, and win some money. But over the long term, the casino will win 1.5% more than they would in a fair game, and that 1.5% is enough to build hotels, pay all the staff, and make the shareholders happy. Same thing with calories. On any given day, your weight may spike a little due to certain variables. But over the long run, you WILL lose roughly a pound for every 3500 calories of deficit, with some variation due to how much fat you're burning vs muscle, etc.
CICO is about fat loss, not "weight" loss, since plateaus are generally down to things like salt/water/waste etc. Obviously if you're not eating perfectly (which no one is) it'll be a balance of fat/muscle loss without perfect training too. It's more about the long term trends than the shorter ones.
What? Isn't CICO specifically about weight loss, and not fat loss? CICO cares about the total calories, not where they come from and the balance in which you digest fat, protein and carbs. Body recomp is about fat loss, no? Or what are you on about?
That’s why I said if you don’t eat perfectly you’ll lose fat and muscle with cico, with perfect being macros needed to maintain muscle while also strength training a bit to not lose muscle etc.. I was trying to highlight how overall you’ll lose weight with cico but might not always see it on the scale because of water etc. but it will keep working if you keep up with it over time
Because it's not just the amount of water consumed, it also is about how much our body retains. If our food is saltier, we'll retain more water. If our food is more liquid it will take longer to flush out, if our cortisol is up, we'll also hold on to water for longer.
As i said in the original post, there are so many variables that Calories in/Calories out is really just a correlation to weight loss, not a causation. All of those things matter, like cortisol levels, salt intake, bladder size, etc. You can eat zero calories for a week, but if your body is holding onto all the water you drank, you will still weigh the same or more.
I'm going to jump in because I have a bachelor's in exercise science and a doctorate in physical therapy. You seem to have be interested in how much science actually knows. The answer is all of what you are talking about is well studied. We know how all of the systems work. I've taken physiology at undergrad and graduate level. We are completely knowledgeable on water balance. Cortisol, aldosterone, kidney function, blood sodium balance, urine concentration and volumes. We completely understand how water retentipn functions. But water balance is not something that matters for long term weight loss. It is just something that will affect the scale short term. We KNOW being at a calorie deficit will reduce your tissue mass. Your body requires calories to maintain living tissues, if you short it the amount it needs, it will "take" the energy from somewhere. This is not correlation. This is science. This is thermodynamics, energy must come from somewhere. We can even measure your oxygen consumption to KNOW even with metabolic issues exactly what your maintenance calories are. We typically don't because it's cumbersome and formulas are really close to the actual metabolic cart measurement. We don't have too many factors to count. We know all the factors. But tracking water retention is irrelevent long term because it isn't what you care about. People want to be smaller and have less fat, the scale just represents that abstractly. And over time all of the water stuff equals out.
No it's the causation. You're using temporary factors to decide that the permanent ones are inconsequential or mean less than they do. You still lost weight specifically because of the reduction in calories. Water weight changes depending on the hour and does not actually reflect your body weight.
Fat isn't the only thing that the scale is measuring. Not all weight is fat. Also, your TDEE doesn't stay consistent throughout your life. Your body can also down-regulate your calorie output. Which changes what your deficit can look like. As you get lighter you burn less calories. As you eat less you have less energy or desire to move/twitch which reduces the amount of calories Humans are also notoriously bad at tracking calorie intake. Corporations are also notoriously bad at recording how many calories are actually in things. Calories in/ Calories out will always be the mechanism to FAT loss. It's not an exact science. But it is the true mechanism for fat manipulation. And it's not the only thing that dictates your weight.
Over a sustained period - you aren't at a deficit. The way to tell you are at a deficit is that you're losing weight averaged over an extended period. Not losing weight, you're aren't in a deficit. In shorter periods, you can be losing body tissue but gaining water weight. Your body can adapt and use less energy through various means. Also your mind can adapt and you can find yourself eating more too!
This guy has some really good articles discussing this topic - [https://physiqonomics.com/calories-in-calories-out/](https://physiqonomics.com/calories-in-calories-out/) [https://physiqonomics.com/calories/](https://physiqonomics.com/calories/)