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  • #16
    Originally posted by Elliot View Post
    This is a very misleading statement, because you are changing units. Fat has about twice the energy per mass, but about six times the energy per molecule, if you only count energy produced in the mitochondria and you only consider fatty acids of about 17 carbons. But I don't see why you think this is so significant. Larger molecules should produce more energy. They are larger. If you want to derive an equal amount of energy from carbs, you could simply burn more of them.
    Well done Elliot! Avogadro is happy.

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    • #17
      Originally posted by John Caton View Post
      You are absolutely correct. Hormones change in response to current and past diet and activity, and then dictate what happens with your next meals and activity.
      Yes and no, hormonal activities mirroring what you are doing, they respond and carry out tasks that are necessary in our bodies due to what we are doing or not doing. So when I get stressed is it the stress hormones that makes me stressed or are stresshormones elevated because I am stressing around or having stressful thoughts? Hormones can change very fast depending on activities, so saying that it's hormones that "dictate" what happens with your next meals and activity are wrong imo, they just carry out what they have to do based on lifestyle.


      Originally posted by John Caton View Post
      I don't know how close you are to the volcano down there but hope you're safe. Peace.
      In our country we have some volcanoes in the mountains that now and then spew out lava, ashes and smoke. Now after more than 100 years of relative silence the Cotopaxi volcano is getting angry again. I live at the coast so it doesn't affect me unless I have to travel to these places...
      Last edited by Gorbag; 08-19-2015, 01:22 PM.
      "All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."

      - Schopenhauer

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      • #18
        Originally posted by Elliot View Post
        This is a very misleading statement, because you are changing units. Fat has about twice the energy per mass, but about six times the energy per molecule, if you only count energy produced in the mitochondria and you only consider fatty acids of about 17 carbons. But I don't see why you think this is so significant. Larger molecules should produce more energy. They are larger. If you want to derive an equal amount of energy from carbs, you could simply burn more of them.
        It isn't as misleading as you say, despite the differences of molar mass.

        Consider 18 carbon stearic acid compared to glucose. The molar mass of stearic acid is 1.576X that of glucose. Molar mass difference doesn't explain the 2.25X advantage stearic acid has over glucose in caloric potential and certainly not the 6X advantage stearic acid has over glucose in potential ATP.

        In a prior exchange we had on a different thread, we both acknowledged that fats and glucose both convert to acetyl CoA to attain common molar mass prior to mitochondrial action, but you acknowledged then that fats yield additional ATP through the Fatty Acid Spiral. So, over and above molar mass differences, that you call misleading, the fact remains that saturated fats, in particular, are a more efficient energy source than glucose.

        Except, I will add for my friend Gorbag who never agrees with what I say, for quick energy access for training purposes or escaping the clutches of tigers. Then, glucose from glycogen, wins hands-down. But, for sustained endurance of life energy at the cellular level, fats win.
        Stop by to visit at http://primalways.net
        Old Paths ... New Journeys

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        • #19
          Originally posted by John Caton View Post
          It isn't as misleading as you say, despite the differences of molar mass.

          Consider 18 carbon stearic acid compared to glucose. The molar mass of stearic acid is 1.576X that of glucose. Molar mass difference doesn't explain the 2.25X advantage stearic acid has over glucose in caloric potential and certainly not the 6X advantage stearic acid has over glucose in potential ATP.
          You are stating these numbers without units, which makes them somewhat meaningless. Stearic acid has about six times the energy of a molecule of glucose, per molecule, when counting only the energy produced in the mitochondria. Don't forget the energy produced outside of the mitochondria during glycolysis.
          Originally posted by John Caton
          In a prior exchange we had on a different thread, we both acknowledged that fats and glucose both convert to acetyl CoA to attain common molar mass prior to mitochondrial action, but you acknowledged then that fats yield additional ATP through the Fatty Acid Spiral. So, over and above molar mass differences, that you call misleading, the fact remains that saturated fats, in particular, are a more efficient energy source than glucose.
          "Efficiency" is a relative term here. So you get more energy per molecule? Why is energy-per-molecule the important quantity here? Imagine if we measured a single starch granule in energy-per-molecule. It would be gigantic. Perhaps, by this metric, we should be eating starch instead of fat.

          Here is another metric: energy produced per oxygen consumed. Obviously, glucose looks better when compared this way, because glucose provides more of its own oxygen. In this way, burning glucose is more "efficient."
          My opinions and some justification

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          • #20
            A mole of glucose = 180.156 grams. A mole of stearic acid = 284.48 grams. That is a ratio of 1:1.576

            What uncommon units are you referring to?
            Stop by to visit at http://primalways.net
            Old Paths ... New Journeys

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            • #21
              Maybe the mass and weight of the average fat molecule compared to the glucose molecule should be calculated also?

              This thread is a very good example in how to get lost in the “minutia” of human physiology - sometimes less information and knowledge on a subject can be better for practical decision making…
              "All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."

              - Schopenhauer

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              • #22
                Originally posted by John Caton View Post
                A mole of glucose = 180.156 grams. A mole of stearic acid = 284.48 grams. That is a ratio of 1:1.576

                What uncommon units are you referring to?
                I never said "uncommon." But earlier you claimed that fat has 2.25 times as much energy than glucose. Yes, this is true per mass. Then you said it has six times the energy of glucose. This is true per molecule. Here is the quote:
                Originally posted by John Caton
                Molar mass difference doesn't explain the 2.25X advantage stearic acid has over glucose in caloric potential and certainly not the 6X advantage stearic acid has over glucose in potential ATP.
                So the numbers are expressed with different units. Here is your earlier quote, which prompted my original post in this thread:
                Originally posted by John Caton
                I know and acknowledge that what I say next makes little sense to you; based on your calorie based assumptions, fat should only deliver 2X the energy as carbs and it is slower to be mustered for quick energy like you'd derive from glycogen, but when at its full potential, driven by proper hormonal signals, high saturated fat will deliver 6X the energy of glucose, not the 2X you'd expect from its calorie count.
                Fat provides both 6X the energy of glucose and 2X (really 2.25X) the energy of glucose, because these are expressed with different units. It provides 6X the energy (per molecule, assuming we are talking about larger molecules), and 2X (per mass). It does both, because these are different measurements using different units.
                My opinions and some justification

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                • #23
                  It boggles the mind that some people implicitly think that the body prefers a fuel type more than another one. makes absolutely no sense. While all this discussion about energy yield per molecule or mass is interesting (in an academic sense), it does not change how metabolism works:

                  - in the absence of a ready-to-be-burnt fuel other than fat, the body will use fat from reserves
                  - if any fuel type other than fat is present, the body will burn that
                  - this is not black and white, it has to do with average because while fat burning is blunted in the presence of carbs, it is not stopped. And vice-versa: you still use glucose in the fasting state (brain) while most of the body will use fat (muscles, etc) in the context of glycogen depletion.

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                  • #24
                    Originally posted by Man View Post
                    It boggles the mind that some people implicitly think that the body prefers a fuel type more than another one. makes absolutely no sense. While all this discussion about energy yield per molecule or mass is interesting (in an academic sense), it does not change how metabolism works:

                    - in the absence of a ready-to-be-burnt fuel other than fat, the body will use fat from reserves
                    - if any fuel type other than fat is present, the body will burn that
                    - this is not black and white, it has to do with average because while fat burning is blunted in the presence of carbs, it is not stopped. And vice-versa: you still use glucose in the fasting state (brain) while most of the body will use fat (muscles, etc) in the context of glycogen depletion.
                    Perhaps, it boggles your mind?

                    Really, none of us are making totally inaccurate statements. We're just emphasizing different pieces of a bigger picture that truly should boggle the mind.

                    Actually, when glucose is available, the body will preferentially use it first and store fat for times when food may not be so abundant. But, the utilization of glucose for energy is limited by the GLUT4 shuttle and insulin to trigger GLUT4 transport. Then, in the cell some of glucose's carbon is utilized to produce CO2 and not to energy. Therefore, energy output is limited and more has to be consumed to offset the loss. Again, this is not a problem because it is assumed that more and more glucose is available in this scenario. In the same scenario, if we are putting glucose in faster than the cells can take it up, the body will opt to store it as glycogen for short term access and fat for longer term access. Now, if we can sync our consumption of glucose producing carbs to our activities to avoid long term storage of fat, or if we raise our activity levels to keep glycogen stores in a deficient state, then fat gain doesn't happen. That's fine, if you can do it.

                    Back to the mass-to-energy debate. There really is no debate here because we aren't dealing with Total energy anyway. These aren't nuclear reactions. We aren't making complete mass-to-energy conversions with fats or carbs. Since we aren't, then the debate has to be about how much of the available energy is gleaned from the simple chemical reactions within the cell. Mass differences would only be important if both macros underwent identical chemical reactions. Eventually, they do; when both reach the acetyl CoA stage. But, leading up to that point, beta oxidation of fatty acids yields additional available energy that glucose does not. Greater mass is the explanation here, but only when considering the relative difference between different fatty acids, not the difference with glucose. The more carbon in the fatty acid, the more times the fatty acid has to be chemically cycled in the Fatty Acid Spiral, specific to fats. The more cycles, the more energy gleaned. That is beneficial, is it not? I say it is more efficient, despite that being a relative term, in the same sense that it is more efficient to carry 40,000 lbs in a truck, rather than carrying 1,000 pounds in the trunk of 40 cars. How's that for mixing units, Elliott?

                    I'm getting long winded. Sorry.

                    Elliott is correct. One can easily offset the available energy derived from fats by just eating more carbs. If you time the intake and energy expenditure correctly, you won't gain weight from fat storage. If you don't time it right, you will pack on fat.

                    On the other hand, you can be a predominant fat burner by assuming food will remain abundant and glean much more available energy for life processes and worry less about fat storage and weight gain. Put it in and burn it off. That's efficiency.

                    Finally, for Elliott and Artbuc, if you don't want to consider the 6X advantage at the molecular level, look at it gram to gram.

                    If Y represents the number of molecules per gram, 1Y represents Stearic Acid molecules per gram. Therefore, glucose has 1.576Y molecules per gram.

                    If Z represents the energy in ATP output per molecule, then 1Z represents the energy output of glucose and the output of Stearic Acid is 6Z.

                    Y * Z = energy/gram. Glucose energy per gram is 1.576YZ. Stearic Acid fat energy per gram is 6YZ. Gram for gram, fat yields 3.81 X more energy. And this is in addition to heat energy fat produces without ATP. Kinda deflates the 2.25X difference that calorie counters assume.
                    Last edited by John Caton; 08-20-2015, 05:08 AM.
                    Stop by to visit at http://primalways.net
                    Old Paths ... New Journeys

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                    • #25
                      With respect, I don't believe the efficiency or relative energy difference is particularly useful to dietary goals, since we can simply eat as much saturated fat or as much carbohydrate as we want. But there can be significant differences in outcomes related to diets using different mixes of the two, regardless of calories. And there are significant differences related to the food "carriers" that bring those in to the body as well, particularly in relation to glucose-containing foods and how they are processed in the body. Using highly refined carb sources is bad for everyone, period.
                      Last edited by NewOldGuy; 08-20-2015, 06:43 AM.

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                      • #26
                        Originally posted by John Caton View Post

                        If Y represents the number of molecules per gram, 1Y represents Stearic Acid molecules per gram. Therefore, glucose has 1.576Y molecules per gram.

                        If Z represents the energy in ATP output per molecule, then 1Z represents the energy output of glucose and the output of Stearic Acid is 6Z.

                        Y * Z = energy/gram. Glucose energy per gram is 1.576YZ. Stearic Acid fat energy per gram is 6YZ. Gram for gram, fat yields 3.81 X more energy. And this is in addition to heat energy fat produces without ATP. Kinda deflates the 2.25X difference that calorie counters assume.
                        Hooraay! Congratulations John, you have by this masterpiece of a thread proved that the entire community of scientist all over the world have all been completly wrong on this subject! Now prepeare yourself to be a Nobel laurate and to eat paleo food at the kings table in Stockholm Sweden...
                        "All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."

                        - Schopenhauer

                        Comment


                        • #27
                          Originally posted by John Caton View Post
                          That is beneficial, is it not?
                          I don't see why it would be.
                          Originally posted by John Caton
                          I say it is more efficient, despite that being a relative term, in the same sense that it is more efficient to carry 40,000 lbs in a truck, rather than carrying 1,000 pounds in the trunk of 40 cars.
                          I don't see how the analogy applies here. Really, how is it beneficial to get more energy per molecule? Don't use an analogy; give me an actual, direct explanation of the benefit.
                          Originally posted by John Caton
                          I'm getting long winded. Sorry.

                          Elliott is correct. One can easily offset the available energy derived from fats by just eating more carbs. If you time the intake and energy expenditure correctly, you won't gain weight from fat storage. If you don't time it right, you will pack on fat.
                          And your solution is to eat fat, instead? Every time you eat fat, you pack on fat. You might burn it later, but it does not all get burned immediately. It sounds like your solution to avoid possibly converting glucose into fat is...to eat fat, which is already fat. No conversion necessary.
                          Originally posted by John Caton
                          On the other hand, you can be a predominant fat burner by assuming food will remain abundant and glean much more available energy for life processes and worry less about fat storage and weight gain. Put it in and burn it off. That's efficiency.

                          Finally, for Elliott and Artbuc, if you don't want to consider the 6X advantage at the molecular level, look at it gram to gram.

                          If Y represents the number of molecules per gram, 1Y represents Stearic Acid molecules per gram. Therefore, glucose has 1.576Y molecules per gram.

                          If Z represents the energy in ATP output per molecule, then 1Z represents the energy output of glucose and the output of Stearic Acid is 6Z. Y * Z = energy/gram. Glucose energy per gram is 1.576YZ. Stearic Acid fat energy per gram is 6YZ. Gram for gram, fat yields 3.81 X more energy. And this is in addition to heat energy fat produces without ATP.
                          You mention this without mentioning the heat energy glucose produces.
                          Originally posted by John Caton
                          Kinda deflates the 2.25X difference that calorie counters assume.
                          No, because you're talking about ATP, and they're talking about total energy.

                          Please explain why getting more ATP per molecule or per mass is beneficial. Please do not provide an analogy; I want a direct explanation of benefit.
                          Last edited by Elliot; 08-20-2015, 10:17 AM.
                          My opinions and some justification

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                          • #28
                            Benefits? Gee, Elliott, that's a tough one.

                            Aside from increased energy to power your brain, contract your muscles, pump your heart and synthesize your RNA/DNA, I can't think of one.
                            Stop by to visit at http://primalways.net
                            Old Paths ... New Journeys

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                            • #29
                              The carb battle is humorous. Both w.o.e. work depending on the individual. I might be biased but there seems to be more evidence and n=1 in favor of low carb. As someone who puts hunting/gathering into practice animal food gets you a lot more bang for your buck. You have to spend days gathering enough veggies/tubers to nourish your family but it can take only a few hours to harvest weeks of food from a single kill.

                              Sent from my SM-N910V using Tapatalk

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                              • #30
                                Originally posted by John Caton View Post
                                Benefits? Gee, Elliott, that's a tough one.

                                Aside from increased energy to power your brain, contract your muscles, pump your heart and synthesize your RNA/DNA, I can't think of one.
                                Johnn, you've changed units again. You've been doing this frequently throughout this thread. Fat has more energy per mass than glucose, and it has more energy per molecule. Neither of these is total energy. To get from energy per mass to total energy, you would need to know the total amount of mass being burned.

                                As I said before, to get an equal amount of energy from carbs, you could simply burn more of them.

                                Total energy is neither energy per mass nor energy per molecule!
                                Last edited by Elliot; 08-20-2015, 07:30 PM.
                                My opinions and some justification

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