7 ms·

Your assumption about the laws of thermodynamics predicates that the "Energy out" part of the equation is not somehow effected by the type of "Energy in" (Addin

Your assumption about the laws of thermodynamics predicates that the "Energy out" part of the equation is not somehow effected by the type of "Energy in" (Adding wet sticks to a fire will not produce as much released energy as adding dry sticks or gasoline soaked sticks) The general argument about carbs or any food with high glycemic response is that these foods are like adding "wet sticks" to the fire. There's considerable science and anicdote to support this. If you're interested (And not simply not throwing around pithy sound bytes about physics) check out: Why we get fat (And what to do about it) By Gary Taubes (http://garytaubes.com/ http://garytaubes.com/) For some very compelling anicdotal evidence (That also supports some concepts of Paleo) check out http://www.reddit.com/r/keto http://www.reddit.com/r/keto

tjogin 14y ago
Taubes has been refuted so many times it's astonishing that anyone still cites him. Compelling anecdotal evidence is an oxymoron, especially when the scientific evidence to the contrary is so strong.
- Selfcommit 14y ago
  I've seen some work contradicting him, but would be interested in seeing something refuting him. Your phrase "Compelling anecdotal evidence is an oxymoron" seems strange. If 5 people told me they saw my wallet outside, I'd be compelled to check, by anecdote, if I'd dropped it on my way in. Please show me your science.
dalke 14y ago
Your metaphor of adding wet sticks to a fire is flawed, from a thermodynamics argument. Assuming that the fire is large enough, it will dry out the wet sticks through evaporation/boiling, and the wood's total contribution to the heat ("energy out") will be unchanged. Now, of course for the people sitting around the fire, some of the heat that would be warming them up or used for cooking is instead used to force a phase change in the water, so it won't be as much "useful" heat, but that meaning of utility - which I believe is the one you want - is outside of thermodynamics. For what it's worth, "for some very compelling anecdotal evidence" of the thermodynamic approach, see The Hacker's Diet at http://www.fourmilab.ch/hackdiet/ http://www.fourmilab.ch/hackdiet/ , which uses the "Rubber Bag" model. Unlike the garytaubes.com web site, the entire book and supporting materials are available for free download. The basic premise is the thermodynamic "if you eat more calories than you burn, you gain weight; if you eat fewer calories than you burn, you lose weight." (See also 'Food and fact' where "The rubber bag view of the body and considering only the calorie content of food is obviously oversimplified." and some of the complications are mentioned.) I believe you are making a different argument, which is that you can't always measure the caloric impact of foods. Under the Hacker Diet, that makes little difference. It uses a feedback system based on weight trends rather than specific calorie counting. There's no need to know that oak combustion produces about 15MJ/kg and boiling water from room temperature takes about 3MJ/kg, because it only looks at 'is there enough heat'?
- Selfcommit 14y ago
  Thanks for the links on the Hacker diet, the rubber bag concept sounds interesting, I'll check it out. As for my metaphor - actually I think it holds very true to what you're saying. You pre-qualified that the fire be hot enough to overcome the dampness of the sticks. That's my exact point. Think of the water as insulin and the stick itself as the fat you want to burn. If you're consistently slamming yourself into insulin shock then you'll never burn fat, and you'll end up looking like most of America(Myself included). It takes very little insulin response to put our fire out. No one is refuting thermodynamics here - simply stating that making the assumption that the body is a perfect machine (Or set at some guaranteed rate of efficiency) is a flawed outlook. Taubes makes a great case for this in his examination of Native American Women and their children.
  - dalke 14y ago
    Now you're using the body's metabolism to explain the metaphor to explain the body's metabolism. I don't think it's supposed to work that way. :) To highlight some of the difficulties: So, insulin shock is the specific heat of water and/or the heat of evaporation? Does fire "slam into" the water? As a technical point, there's a distinction between heat and temperature. The fire does not need to be "hot", it just needs to have enough heat to evaporate some of the water on the new wood, and of course hot enough to catch the wood on fire. At that point the reaction becomes self-sustaining. I don't know how to apply that heat/temperature distinction to the metaphor. If the "fire is out" then what are we using to survive? (These are rhetorical. I think I know the point you're trying to get across.) Also, what does a "perfect machine" have to do with anything? Surely not from a thermodynamics viewpoints. I can't think of anyone who thinks of the human body as a perfect machine, and I have a hard time thinking of what that would even mean.
    - Selfcommit 14y ago
      While I'm amused (Really I am, no sarcasm!) with the extension of the fire concept - I think you're just pulling at semantics of my metaphor =) You make a valid point - lets pull heat and temperature out of it. I'll take the whole metaphor out. If I were to waterdown the through process of ketogenic diets (which are what I'm talking about and share some things with Paleo) I would explain them as such: Insulin prevents your body from breaking down it's natural stores of energy. When you eat anything with a high glycemic index (Which is most food in the American diet) you have an insulin reaction. While having an insulin reaction, you don't burn fat stores. If you can't burn your fat stores, you don't lose weight. If you can't burn your fat stores and you run out of immediately available energy your bodies 'fire' dims (You crash after that sugar rush) Ketogenic diets are the only diets that make sense to me, because they so easily explain the different states of weight gain/loss and energy level. I'm interested in hearing other methods of weight management.. but I really feel the ketogenic concept explains the body best.

tjogin 14y ago

Taubes has been refuted so many times it's astonishing that anyone still cites him. Compelling anecdotal evidence is an oxymoron, especially when the scientific evidence to the contrary is so strong.

Selfcommit 14y ago
I've seen some work contradicting him, but would be interested in seeing something refuting him. Your phrase "Compelling anecdotal evidence is an oxymoron" seems strange. If 5 people told me they saw my wallet outside, I'd be compelled to check, by anecdote, if I'd dropped it on my way in. Please show me your science.

dalke 14y ago

Your metaphor of adding wet sticks to a fire is flawed, from a thermodynamics argument. Assuming that the fire is large enough, it will dry out the wet sticks through evaporation/boiling, and the wood's total contribution to the heat ("energy out") will be unchanged. Now, of course for the people sitting around the fire, some of the heat that would be warming them up or used for cooking is instead used to force a phase change in the water, so it won't be as much "useful" heat, but that meaning of utility - which I believe is the one you want - is outside of thermodynamics. For what it's worth, "for some very compelling anecdotal evidence" of the thermodynamic approach, see The Hacker's Diet at http://www.fourmilab.ch/hackdiet/ http://www.fourmilab.ch/hackdiet/ , which uses the "Rubber Bag" model. Unlike the garytaubes.com web site, the entire book and supporting materials are available for free download. The basic premise is the thermodynamic "if you eat more calories than you burn, you gain weight; if you eat fewer calories than you burn, you lose weight." (See also 'Food and fact' where "The rubber bag view of the body and considering only the calorie content of food is obviously oversimplified." and some of the complications are mentioned.) I believe you are making a different argument, which is that you can't always measure the caloric impact of foods. Under the Hacker Diet, that makes little difference. It uses a feedback system based on weight trends rather than specific calorie counting. There's no need to know that oak combustion produces about 15MJ/kg and boiling water from room temperature takes about 3MJ/kg, because it only looks at 'is there enough heat'?

Selfcommit 14y ago
Thanks for the links on the Hacker diet, the rubber bag concept sounds interesting, I'll check it out. As for my metaphor - actually I think it holds very true to what you're saying. You pre-qualified that the fire be hot enough to overcome the dampness of the sticks. That's my exact point. Think of the water as insulin and the stick itself as the fat you want to burn. If you're consistently slamming yourself into insulin shock then you'll never burn fat, and you'll end up looking like most of America(Myself included). It takes very little insulin response to put our fire out. No one is refuting thermodynamics here - simply stating that making the assumption that the body is a perfect machine (Or set at some guaranteed rate of efficiency) is a flawed outlook. Taubes makes a great case for this in his examination of Native American Women and their children.
- dalke 14y ago
  Now you're using the body's metabolism to explain the metaphor to explain the body's metabolism. I don't think it's supposed to work that way. :) To highlight some of the difficulties: So, insulin shock is the specific heat of water and/or the heat of evaporation? Does fire "slam into" the water? As a technical point, there's a distinction between heat and temperature. The fire does not need to be "hot", it just needs to have enough heat to evaporate some of the water on the new wood, and of course hot enough to catch the wood on fire. At that point the reaction becomes self-sustaining. I don't know how to apply that heat/temperature distinction to the metaphor. If the "fire is out" then what are we using to survive? (These are rhetorical. I think I know the point you're trying to get across.) Also, what does a "perfect machine" have to do with anything? Surely not from a thermodynamics viewpoints. I can't think of anyone who thinks of the human body as a perfect machine, and I have a hard time thinking of what that would even mean.
  - Selfcommit 14y ago
    While I'm amused (Really I am, no sarcasm!) with the extension of the fire concept - I think you're just pulling at semantics of my metaphor =) You make a valid point - lets pull heat and temperature out of it. I'll take the whole metaphor out. If I were to waterdown the through process of ketogenic diets (which are what I'm talking about and share some things with Paleo) I would explain them as such: Insulin prevents your body from breaking down it's natural stores of energy. When you eat anything with a high glycemic index (Which is most food in the American diet) you have an insulin reaction. While having an insulin reaction, you don't burn fat stores. If you can't burn your fat stores, you don't lose weight. If you can't burn your fat stores and you run out of immediately available energy your bodies 'fire' dims (You crash after that sugar rush) Ketogenic diets are the only diets that make sense to me, because they so easily explain the different states of weight gain/loss and energy level. I'm interested in hearing other methods of weight management.. but I really feel the ketogenic concept explains the body best.