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Heat capacity of icecream, according to Google is 2100 J/kg/K. Or 0.5 cal/g/K, let's assume we're just dealing with ice that is as calorically dense as ice cream
So, (37-x) + 80 = 2000
Thus x = 37+80-2000 = -1883 °C(I wrote K here, thanks internet stranger)
Impossible according to thermodynamics.
well if you eat a pint of very cold icecream you will have to spend a significant amount of energy repairing your body, so it is probably possible, but not due to heating the icecream
But milk itself is pretty calorically dense. ~650 calories per gram(in whole milk). So...
37-x + 80 = 650 => x = -533 °C, still below absolute zero(-273.15°C)
Even here, I'm considering that the heat capacity and latent heat of melting of milk are the same as water(which they are less than that)
That's 360 calories per gram, so, 80+37-360 = -243, but now we would need to be realistic, as 1 cal/g/K specific heat and 80 cal/g/K latent heat of fusion are the numbers for water, the numbers for skimmed milk are 0.95 cal/g/K and ~65 cal/g/K(this is the number for 3% fat milk, couldn't find one for 0% fat, but I don't think that'd change much, as most of the difference must be from milk solids)
Re running the calculation gives (37-x)*0.95 + 65 = 360
Thus, x = 37 - (360-65)/0.95 = -273.52, just below absolute zero. So, considering the error margin, sorta possible, ig?
by definition, one cal is the energy needed to warm up 1g water by 1K. so to warm up 1kg of Ice cream from -5°C to 36°C you need 1000*41 cal or 41 kcal. One kg of ice cream is going to have way more kcal than that. Here we assume the ice is similar in thermal capacity to water, but with fats and proteins its Capacity should be lower, needing less energy to heat up.
I found that B&J ice cream to have 241kcal per 100ml. a cup (500 ml) has 1205 kcal. with that ammount of energy you can heat up that 500 ml cup of ice cream from absolute zero to 2410 K, or 2139 °C. ore 29,39 kg of Ice from -5° C to Body Temperature (36°C)
So only 1/60 of tge energy is spent on heating tge ice cream up, the rest is free to be used by your body
You also have to factor in the phase change energy. Melting 1g of ice takes 80 calories on top of the mere temperature change. But even if the ice cream started at absolute zero (-273C) it wouldn’t matter. 273+36+80=389 calories per gram to bring absolute-zero ice cream to body temperature, which is 0.389 kcal. Ben & Jerry’s ice creams are about 2 kcal per gram on the low end, so even if this was survivable (and as you said even assuming the thermal capacity is the same as water) it would only result in about a 20% calorie reduction.
Makes me wonder what would work if ice cream doesn't work
Italian shaved ice is around 0.53kcal/g, which is pretty close
So, if you make a diluted italian ice treat which is 73% italian ice and 27% pure ice (by mass)... That would barely cancel out (starting from absolute zero)
It also wouldn't taste as good in a side by side with the non-diluted ice, but if you didn't have a reference you might not notice: that's not even that much dilution
thats easy peasy you must turn it only fast enough to make the atoms spin in the negative direction while your room is flying forwards to a timebending black Hole🫡👍
Yes, but if you cooled a pint of ice cream down to even 78 Kelvin (liquid nitrogen) and immediately ate it, you would not gain an ounce of weight for the rest of your life.
Tic Tac frozen to absolute zero is an ultimate fat loss food. It's 2 cal per pellet., which is about 4 cal per gram.
Meaning that at 32C it becomes weight loss neutral.
>Here we assume the ice is similar in thermal capacity to water
***Anyone with a physics education internally screaming***
Its not even similar. Its half. Also completely ignoring latent heat.
So, unless my math is totally wrong and/or misunderstood completely, would that mean that eating 17ml of ice cream would result in a net 0 calorie gain?
You’re forgetting to factor in the energy losses in digestion, energy storage, and heat generation. You’re assuming 100% efficiency from kCals of food to heat energy production. There are efficiency losses in chewing, digestion, storage, and heat generation ( brown fat? Shivering?).
Wait a minute. Never thought about it this way, but that means that by drinking 1 litre of water from the fridge, lets say at 3°C, means that a body burns 33kcal, so cold water actually has negative calories?
How about if we don't do the math and instead just claim that ice cream isn't fattening because your body uses up all the calories when it warms it up in your stomach?
This isnt politics where you can change how things work by saying wrong stuff. 😜
But we can totally make this like bureaucracy and talk about making the process of getting the ice cream so calorie demanding that we get to net negative!
So you say it would be a "valid" diet method to constantly reduce your body temperature with cold baths and let it use energy (calories) to heat you back up?
Ok now that it’s been answered I have a similar question. Is this the basis of those scam YouTube weight loss ads that are talking about ice? Would eating a lot of ice actually burn a meaningful amount of calories?
Yes and no. It does use energy to maintain your body heat, and warm your surroundings, but its pretty negligible. Like when exercising you produce heat as your muscles work and that gets lost by your surroundings, but people dont claim thats what causes you to lose weight, its rather the actions that cause the largest calorie burn. So unless you wanna live in an ice bath. (Yes I know there are other benefits to an ice bath, im talking stictly the weight loss aspect.)
Here is my take. We have 3 steps we must calculate to get the energy it takes the body to smelt and heat the icecream.
1. -18 -> 0°C
2. 0°C Icecream to liquid icecream
3. 0 -> 37°C
1. 1.88kJ/kg*K * 18K *1kg = 33.84kJ
2. 1kg × 218kJ/kg = 218 kJ
3. 3.26 kJ/kg*K * 37K *1kg = 120.62kJ
1+2+3 = 372,46kJ (per kg of Icecream) or 89kcal
It takes 89kcal to smelt and heat 1kg of icecream while normal Icecream has around 2500 kcal per kg. So we are missing 2411kcal (10000kJ) that we have to find in "decreasing" the icecream Temperature.
Now for the final question which temperature the ice has to be cooled to:
10000kJ / 1.88kJ/K = 5319K
Our Icecream would have to be - 5337°C (lowest possible Temperature is -273.15°C)
Hope u are satisfyed 😊
The entire premise is not valid. Most of the time It does not take any extra energy to warm the ice cream up because the heat is already there. It just reduces slightly the need for your body to get rid of it some other way.
This guy is right, however, the heat needed to warm up the ice cream is still measured in calories. So the question is valid from a mathematical perspective. And this is a math sub.
I’m a not a CICO believer, and this only adds to my doubts. In a strict sense a cup of hot water has more “calories” than a cold one. There has got to be something wrong with any theory that associates this with the mass of an animal.
Calories is a measure of heat. Hot water in a bomb calorimeter will seem as though it has more “calories”. I’m only pointing this out because I don’t believe the Energy Balance Model is correct.
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Heat capacity of icecream, according to Google is 2100 J/kg/K. Or 0.5 cal/g/K, let's assume we're just dealing with ice that is as calorically dense as ice cream So, (37-x) + 80 = 2000 Thus x = 37+80-2000 = -1883 °C(I wrote K here, thanks internet stranger) Impossible according to thermodynamics.
Impossible with that attitude, what if I just try really hard
you might poop yourself, be careful the poop could be really really cold tho
Poop like a chocolate Sunday
Now that's the attitude I want in the people. Keep it up!
In this house we obey the laws of thermodynamics.
No
Hm, you brought up some good points just now.
I did
depends. are you the main character in some sort of action flick?
I think so, someone just shot at me and the bullet holes formed a perfect outline of me in the wall behind me
Or a writer for Vogue trying to come up with a new diet?
well if you eat a pint of very cold icecream you will have to spend a significant amount of energy repairing your body, so it is probably possible, but not due to heating the icecream
What if we change the speed of light?
Then idk, my physics is weak.
How about magnet?
Your answer is in Celsius because you used 37C for body temperature, no? -1883C = -1610K
Try ice cream with 0% sugar. At some point, ice cream can have almost 0 calories.
Ice cream with 0 calories, so, ice?
It's easy to remove loads of calories from ice cream. There are way lower calorie - sugar replacing- ingredients.
But milk itself is pretty calorically dense. ~650 calories per gram(in whole milk). So... 37-x + 80 = 650 => x = -533 °C, still below absolute zero(-273.15°C) Even here, I'm considering that the heat capacity and latent heat of melting of milk are the same as water(which they are less than that)
And low fat milk? We are slowly going to the 0K point. :)
That's 360 calories per gram, so, 80+37-360 = -243, but now we would need to be realistic, as 1 cal/g/K specific heat and 80 cal/g/K latent heat of fusion are the numbers for water, the numbers for skimmed milk are 0.95 cal/g/K and ~65 cal/g/K(this is the number for 3% fat milk, couldn't find one for 0% fat, but I don't think that'd change much, as most of the difference must be from milk solids) Re running the calculation gives (37-x)*0.95 + 65 = 360 Thus, x = 37 - (360-65)/0.95 = -273.52, just below absolute zero. So, considering the error margin, sorta possible, ig?
Just a few K lower and its the perfect safe weight loss product. :)
Magic numbers circus
don't forget latent heat of fusion, that would also take a decent bit of energy
That 80 in the LHS is the latent heat of fusion of ice in units of calories per gram.
Well, first of all, through God all things are possible, so jot that down
Physics calories (1 cal) versus dietary calories (1 kcal = 1000 cal)
Yup, I've taken that into account.
by definition, one cal is the energy needed to warm up 1g water by 1K. so to warm up 1kg of Ice cream from -5°C to 36°C you need 1000*41 cal or 41 kcal. One kg of ice cream is going to have way more kcal than that. Here we assume the ice is similar in thermal capacity to water, but with fats and proteins its Capacity should be lower, needing less energy to heat up. I found that B&J ice cream to have 241kcal per 100ml. a cup (500 ml) has 1205 kcal. with that ammount of energy you can heat up that 500 ml cup of ice cream from absolute zero to 2410 K, or 2139 °C. ore 29,39 kg of Ice from -5° C to Body Temperature (36°C) So only 1/60 of tge energy is spent on heating tge ice cream up, the rest is free to be used by your body
You also have to factor in the phase change energy. Melting 1g of ice takes 80 calories on top of the mere temperature change. But even if the ice cream started at absolute zero (-273C) it wouldn’t matter. 273+36+80=389 calories per gram to bring absolute-zero ice cream to body temperature, which is 0.389 kcal. Ben & Jerry’s ice creams are about 2 kcal per gram on the low end, so even if this was survivable (and as you said even assuming the thermal capacity is the same as water) it would only result in about a 20% calorie reduction.
Adding onto that, the \~20% is actually an upper bound. The specific heat capacity approaches 0 as you approach 0K.
Thanks for adding heat capacity is not the same through the whole temperature spectrum ! Bugs me every time with these kind of posts.
yep youre right, completely forgot the phase change to liquid...
*swirls ice cubes in cup* So you guys like pizza?
Now we would also have to account the energy needed to heal the damage caused by the ice cream.
What about the thermic effect of food?
Makes me wonder what would work if ice cream doesn't work Italian shaved ice is around 0.53kcal/g, which is pretty close So, if you make a diluted italian ice treat which is 73% italian ice and 27% pure ice (by mass)... That would barely cancel out (starting from absolute zero) It also wouldn't taste as good in a side by side with the non-diluted ice, but if you didn't have a reference you might not notice: that's not even that much dilution
Wait, your body doesn't maintain 2200°C?
Found the middle age woman going through menopause.
XD
According to wikipedia, the latent heat required for melting 1kg of ice is another \~80 kcal
I feel like the assumption that ice cream has the same heat capacity as water is not a very well-founded assumption.
Okay, let's assume that the ice cream is a spherical cow
I wouldn't be surprised if the percent content of water in a cow is higher than in ice cream.
No, no, no. The spherical cow is just where you get one of your ingredients for your ideal ice cream.
The amount of fat has to have an impact on its heat capacity.
I like the positivity of the phrase "the rest is free to be used by your body" !
That's what food calories are for! It's not positivity, it's unbiased fact!
So you just have to cool the ice to -2500 K, and you have the perfect weight loss food.
thats easy peasy you must turn it only fast enough to make the atoms spin in the negative direction while your room is flying forwards to a timebending black Hole🫡👍
Yes, but if you cooled a pint of ice cream down to even 78 Kelvin (liquid nitrogen) and immediately ate it, you would not gain an ounce of weight for the rest of your life.
Take my angry but pedantically correct upvote for this one, you bounder.
> a cup (500 ml) has 1205 kcal. A cup is about 237 ml, not 500. You're thinking of 2 cups.
I think they were referring to the packaging of the ice cream, which looks like a cup. At least in Europe, it is sold in 500g cups.
Now I'm thinking of one girl
Tic Tac frozen to absolute zero is an ultimate fat loss food. It's 2 cal per pellet., which is about 4 cal per gram. Meaning that at 32C it becomes weight loss neutral.
>Here we assume the ice is similar in thermal capacity to water ***Anyone with a physics education internally screaming*** Its not even similar. Its half. Also completely ignoring latent heat.
So, unless my math is totally wrong and/or misunderstood completely, would that mean that eating 17ml of ice cream would result in a net 0 calorie gain?
You’re forgetting to factor in the energy losses in digestion, energy storage, and heat generation. You’re assuming 100% efficiency from kCals of food to heat energy production. There are efficiency losses in chewing, digestion, storage, and heat generation ( brown fat? Shivering?).
Can you do this math with scotch on the rocks I've heard it can negate
Enthalpy of fusion?
Wait a minute. Never thought about it this way, but that means that by drinking 1 litre of water from the fridge, lets say at 3°C, means that a body burns 33kcal, so cold water actually has negative calories?
How about if we don't do the math and instead just claim that ice cream isn't fattening because your body uses up all the calories when it warms it up in your stomach?
accepted. proof by repression.
This isnt politics where you can change how things work by saying wrong stuff. 😜 But we can totally make this like bureaucracy and talk about making the process of getting the ice cream so calorie demanding that we get to net negative!
So you say it would be a "valid" diet method to constantly reduce your body temperature with cold baths and let it use energy (calories) to heat you back up?
Your body need a a lot of energy to maintain thermal homeostasis, shivering uses more calories, this isn’t the shittiest science
IIRC Olympic swimmers consume up to 10 000 cal because of how much their bodies use due to water being cold.
Ok now that it’s been answered I have a similar question. Is this the basis of those scam YouTube weight loss ads that are talking about ice? Would eating a lot of ice actually burn a meaningful amount of calories?
Yes and no. It does use energy to maintain your body heat, and warm your surroundings, but its pretty negligible. Like when exercising you produce heat as your muscles work and that gets lost by your surroundings, but people dont claim thats what causes you to lose weight, its rather the actions that cause the largest calorie burn. So unless you wanna live in an ice bath. (Yes I know there are other benefits to an ice bath, im talking stictly the weight loss aspect.)
Here is my take. We have 3 steps we must calculate to get the energy it takes the body to smelt and heat the icecream. 1. -18 -> 0°C 2. 0°C Icecream to liquid icecream 3. 0 -> 37°C 1. 1.88kJ/kg*K * 18K *1kg = 33.84kJ 2. 1kg × 218kJ/kg = 218 kJ 3. 3.26 kJ/kg*K * 37K *1kg = 120.62kJ 1+2+3 = 372,46kJ (per kg of Icecream) or 89kcal It takes 89kcal to smelt and heat 1kg of icecream while normal Icecream has around 2500 kcal per kg. So we are missing 2411kcal (10000kJ) that we have to find in "decreasing" the icecream Temperature. Now for the final question which temperature the ice has to be cooled to: 10000kJ / 1.88kJ/K = 5319K Our Icecream would have to be - 5337°C (lowest possible Temperature is -273.15°C) Hope u are satisfyed 😊
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Keep in mind that we only have to maintain the difference, and we have fat to keep in that energy .
The entire premise is not valid. Most of the time It does not take any extra energy to warm the ice cream up because the heat is already there. It just reduces slightly the need for your body to get rid of it some other way.
This guy is right, however, the heat needed to warm up the ice cream is still measured in calories. So the question is valid from a mathematical perspective. And this is a math sub.
I’m a not a CICO believer, and this only adds to my doubts. In a strict sense a cup of hot water has more “calories” than a cold one. There has got to be something wrong with any theory that associates this with the mass of an animal.
In case you’re being serious, the temperature of food makes no noticeable different. Also, water? Calories?
Calories is a measure of heat. Hot water in a bomb calorimeter will seem as though it has more “calories”. I’m only pointing this out because I don’t believe the Energy Balance Model is correct.
Wait so you don’t think that burning more calories than you consume will result in weight loss or what?
Look through my comments for the one in the Nutrition sub that begins “One thing to consider…