Trying to Understand Peat's View of Fat Burning

[pone]

Yeah me neither to be honest. But can understand someone questioning why wouldn't we prefer fat over sugar?

However, these aren't separate things and it's not one or the other. Nor is Peat about blocking the beta oxidation. It's just about improving oxidative phosphorylation and limiting stress hormones, so krebs cyclus will move on and our glycolysis won't be hindered. The latter is very important for utilizing glucose to beneficial substances and wide range of effects. The increased CO2 per ATP for example, is really important for protein structure and pH.

All in all Peat is about favoring efficient energy production from glucose as seen in health and in low stress state.

I just don't have enough understanding of the details of aerobic metabolism to have a clue what you are talking about, and I don't understand Peat's point at all (still). This is the kind of thing we could resolve in a 15 minute face-to-face conversation but is much more difficult in this format.

Is Peat talking about how fat can in some circumstances prevent efficient use of glucose in krebs cycle and electron transport chain? And this effect is something totally different from the question of can fat be burned efficiently within krebs cycle and electron transport chain?

 

[pboy]

theres a difference between being more efficient and being faster, glucose requires more oxygen than fat but can handle it, so you can burn glucose faster than fat, thereby producing more atp and heat in a shorter window of time, where as the same grams of fat would produce more atp and heat in the long run, but even if you had oxygen coming in at a super fast rate fat can only be oxidized so fast, so for anything intense and fast only glucose has the capability to support. It depends on what you are going for, but in my opinion, maybe eat fat before sleep, but why would you not want to be faster during the waking hours? If you kept glycogen stocked throughout the day you would produce much more atp and heat than if you burned fat throughout the day, even though its 'less efficient', you would just have to breath more which in reality if you aren't panting is natural and doesn't take effort to do

 

[SAFarmer]

theres a difference between being more efficient and being faster, glucose requires more oxygen than fat but can handle it, so you can burn glucose faster than fat, thereby producing more atp and heat in a shorter window of time, where as the same grams of fat would produce more atp and heat in the long run, but even if you had oxygen coming in at a super fast rate fat can only be oxidized so fast, so for anything intense and fast only glucose has the capability to support. It depends on what you are going for, but in my opinion, maybe eat fat before sleep, but why would you not want to be faster during the waking hours? If you kept glycogen stocked throughout the day you would produce much more atp and heat than if you burned fat throughout the day, even though its 'less efficient', you would just have to breath more which in reality if you aren't panting is natural and doesn't take effort to do

I don't think I agree with your reasoning and would like you to provide a reference for me to study which support your views, especially the "sugar faster than fat" bit. Also, I specifically asked to provide your definition of "efficient", especially in biochemical or engineering terms. Can you explain this ?

 

[Suikerbuik]

Sorry for that Pone, anyway one day you will know . It's not so difficult, it just takes time and effort to get used to things like this.

So I don't understand why Peat obsesses about the release of free fatty acids during exercise and how he seems to imply that this lowers the amount of energy that the body can produce in aerobic metabolism.

Free fatty acids (especially when unsaturated!!!):
- Interfere with our insulin binding capacity
- Inhibit pyruvate dehydrogenase (an enzyme that converts pyruvate -an end product of the glycolis- to acetyl coa that will be further metabolized in the citric acid cycle, critical because this is what links the glycolysis to the krebs cycle)
- Bind to certain other proteins including those normally receiving hormones (so in short interfering with our hormonal system, leading to a semi-infinite amount of changes within an organism affecting all systems.)
- Increase peroxidation
- and else I forgot or just don't know.

 

[pone]

Free fatty acids (especially when unsaturated!!!):
- Interfere with our insulin binding capacity
- Inhibit pyruvate dehydrogenase (an enzyme that converts pyruvate -an end product of the glycolis- to acetyl coa that will be further metabolized in the citric acid cycle, critical because this is what links the glycolysis to the krebs cycle)
- Bind to certain other proteins including those normally receiving hormones (so in short interfering with our hormonal system, leading to a semi-infinite amount of changes within an organism affecting all systems.)
- Increase peroxidation
- and else I forgot or just don't know.

Which Peat article best summarizes these ideas?

And - the bottom line - what do we do to prevent all of this from happening? Surely he isn't saying eat sugar without any fat? Again, put PUFA aside for now. Assume there is no PUFA in your meal and you focus on mostly saturated and monounsaturated fats.

 

[SAFarmer]

Which Peat article best summarizes these ideas?

And - the bottom line - what do we do to prevent all of this from happening? Surely he isn't saying eat sugar without any fat? Again, put PUFA aside for now. Assume there is no PUFA in your meal and you focus on mostly saturated and monounsaturated fats.

You ask others for references without supplying your own when asked to support your ascertions?

You have to read most of Peat's work to see where he explains his ideas about the role of fat vs sugar . I don't think there is only one "summary" page.

 

[pboy]

you can search for things using the internet if you want referances, or just not agree with me. I don't just make things up. Theres a reason during intense exercise glucose is used instead of fat. Glucose is already mostly saturated with oxygen, so for the body to oxidize it it requires less oxygen per gram than fat (which has almost no oxygen present in it)...which is why under intense exercise, or whenever the heart and respiration rate are fast, oxygen supply begins to lag behind the metabolic demand, which is why the body uses glucose first as support for that state of faster metabolic demand, because it requires less oxygen to utilize than fat, so you have a better chance of keeping up with the metabolic demand. Fat provides more atp per gram, because it is almost deficient in oxygen, so its denser, but due to the fact it lacks oxygen, it requires more oxygen per gram than glucose to be oxidized. So if the metabolic rate and respiration needs are high, oxygen levels are generally tending to fall behind necessity to keep up, so fat, requiring more oxygen to be oxidized, is less likely to be able to keep up. It can always contribute, it pretty much always does, but its a slower steadier contributer. If you run out of glucose and are only running on fat, the glycerol attatched to the triglyceride will almost always be converted in the liver to glucose to attempt to supply the body with...so you don't completely run out, but it doesn't contribute very much

 

[SAFarmer]

you can search for things using the internet if you want referances, or just not agree with me. I don't just make things up. Theres a reason during intense exercise glucose is used instead of fat. Glucose is already mostly saturated with oxygen, so for the body to oxidize it it requires less oxygen per gram than fat (which has almost no oxygen present in it)...which is why under intense exercise, or whenever the heart and respiration rate are fast, oxygen supply begins to lag behind the metabolic demand, which is why the body uses glucose first as support for that state of faster metabolic demand, because it requires less oxygen to utilize than fat, so you have a better chance of keeping up with the metabolic demand. Fat provides more atp per gram, because it is almost deficient in oxygen, so its denser, but due to the fact it lacks oxygen, it requires more oxygen per gram than glucose to be oxidized. So if the metabolic rate and respiration needs are high, oxygen levels are generally tending to fall behind necessity to keep up, so fat, requiring more oxygen to be oxidized, is less likely to be able to keep up. It can always contribute, it pretty much always does, but its a slower steadier contributer. If you run out of glucose and are only running on fat, the glycerol attatched to the triglyceride will almost always be converted in the liver to glucose to attempt to supply the body with...so you don't completely run out, but it doesn't contribute very much

This is what you have said previously :

theres a difference between being more efficient and being faster, glucose requires more oxygen than fat but can handle it, so you can burn glucose faster than fat, thereby producing more atp and heat in a shorter window of time, where as the same grams of fat would produce more atp and heat in the long run,

I have asked for a simple reference to support your statement of glucose being able to burn "faster" aerobically than fat, and needing more oxygen. You are not able to do this yet. In fact, you have now changed your original point ! (probably because you had been forced to go and read up on it ...)

I myself have studied this in detail and spent many hours balancing chemical formulas for the different fats vs glucose "burning". I understand the chemistry. I think you don't. You are confused between grams vs molecules. I will stand by my statement until you can provide a credible reference proving your "point".

 

[Mittir]

Here is a quote from the book, Nutrition for Sport and Exercise
By Jacqueline R. Berning, Suzanne Nelson Steen.. page 22 on oxygen
requirement for glucose and fat. You can read it at books.google.com.

Breakdown of fat to ATP is a slow process and does not supply ATP fast enough to
provide energy for high-intensity exercise....
......
There would be a greater total yield of ATP from fat than from carbohydrate
if the muscle could oxidize fat at a sufficiently higher rate during intense exercise.
A 6-carbon glucose molecule produces 36 ATP, whereas an 18-carbon fatty acid
(stearic acid) produces 147 ATP - a 1.3 greater yield of ATP per carbon molecule.
However, 6 molecules of oxygen are required to oxidize a glucose molecule,
whereas 26 molecules of oxygen are required to oxidize stearic acid. Thus the
oxygen requirement for glucose is 77% less than the oxygen requirement for stearic acid.

 

[SAFarmer]

Here is a quote from the book, Nutrition for Sport and Exercise
By Jacqueline R. Berning, Suzanne Nelson Steen.. page 22 on oxygen
requirement for glucose and fat. You can read it at books.google.com.

Breakdown of fat to ATP is a slow process and does not supply ATP fast enough to
provide energy for high-intensity exercise....
......
There would be a greater total yield of ATP from fat than from carbohydrate
if the muscle could oxidize fat at a sufficiently higher rate during intense exercise.
A 6-carbon glucose molecule produces 36 ATP, whereas an 18-carbon fatty acid
(stearic acid) produces 147 ATP - a 1.3 greater yield of ATP per carbon molecule.
However, 6 molecules of oxygen are required to oxidize a glucose molecule,
whereas 26 molecules of oxygen are required to oxidize stearic acid. Thus the
oxygen requirement for glucose is 77% less than the oxygen requirement for stearic acid.

Hi Mitter

I would prefer pone to provide his own references, unless you agree with him?
Second, I would hesitate to use a quote from a book on sports nutrition and exercise as reference for authority on biochemistry calculations ...

 

[pboy]

I typod the first post, but if you read what I said that was what was implied, and what I put in the second post. Mittirs post basically says the same thing. I dont understand why you cant look anything up yourself...you expect each person who posts everything on the internet to cite with referances every post?... and then wont take certain sources as valid?

im not trying to be rude...I read usually for a few hours every day and I don't bookmark everything or remember the exact websites I get things from, but Im not someone who takes anything lightly and just spells it out if I don't have a good idea of what I am saying

 

[SAFarmer]

I typod the first post, but if you read what I said that was what was implied, and what I put in the second post. Mittirs post basically says the same thing. I dont understand why you cant look anything up yourself...you expect each person who posts everything on the internet to cite with referances every post?... and then wont take certain sources as valid?

im not trying to be rude...I read usually for a few hours every day and I don't bookmark everything or remember the exact websites I get things from, but Im not someone who takes anything lightly and just spells it out if I don't have a good idea of what I am saying

I most certainly dont take all sources as valid. Anybody that does so is naive at best. Any credible source need to be able to explain the logic and/or science (chemistry in this case) in order to be verified by peers and critics to be able to stand up to review. Anyone can write a book. It does not make them credible or knowledgeable.

 

[Mittir]

Hi Mitter

I would prefer pone to provide his own references, unless you agree with him?
Second, I would hesitate to use a quote from a book on sports nutrition and exercise as reference for authority on biochemistry calculations ...

I did not read the thread and i do not know what pone is talking about.
You quoted pboy in red and i was responding to that.

glucose requires more oxygen than fat

I know sports books are not reliable source of biochemistry calculation.
The authors did not do their own calculation, they cited other sources.
I thought these are basic science and easily verifiable. I chose that
book because they were talking about limitation of fat burning in intense exercise.
RP has also talked about this and how body shifts from glucose to fat burning during exercise
and wastes glucose by creating lactic acid. This is the effect of "Randle Cycle".
Here is a link to a slides from a biochemistry text book which shows 18 carbon stearic acid
provides 120 ATP and 3 molecules of glcuose ( 18 carbon ) provide 96 ATP.
I have seen different number of ATP for glucose before, 30-38.
That sports book is using 147 ATP for stearic acid and this biochemistry book is using 122,
it is still higher than 96. Both books claim 26 molecules of oxygen needed for
stearic acid oxidation and 6 molecules for glucose. 3 molecule of glucose ( 18 carbon)
use 18 molecule of oxygen. Stearic acid uses more oxygen than glucose per carbon.

Biochemistry
Jeremy M. Berg (Author), John L. Tymoczko (Author), Lubert Stryer (Author)

Page 14 and 15
http://www.uccs.edu/~sbraunsa/Images/48 ... ab-2pp.pdf

 

[Such_Saturation]

Fat and sugar oxidation require the mithochondrion and in some cases the peroxisome and then you get more steps for odd numbered chains... glycolysis is simpler and this is the danger when you ask your body to start compromising efficiency. Also I'd like to see you deadlift a small tree while eating just fat.

 

[SAFarmer]

Hi Mitter

I would prefer pone to provide his own references, unless you agree with him?
Second, I would hesitate to use a quote from a book on sports nutrition and exercise as reference for authority on biochemistry calculations ...

I did not read the thread and i do not know what pone is talking about.
You quoted pboy in red and i was responding to that.

glucose requires more oxygen than fat

I know sports books are not reliable source of biochemistry calculation.
The authors did not do their own calculation, they cited other sources.
I thought these are basic science and easily verifiable. I chose that
book because they were talking about limitation of fat burning in intense exercise.
RP has also talked about this and how body shifts from glucose to fat burning during exercise
and wastes glucose by creating lactic acid. This is the effect of "Randle Cycle".
Here is a link to a slides from a biochemistry text book which shows 18 carbon stearic acid
provides 120 ATP and 3 molecules of glcuose ( 18 carbon ) provide 96 ATP.
I have seen different number of ATP for glucose before, 30-38.
That sports book is using 147 ATP for stearic acid and this biochemistry book is using 122,
it is still higher than 96. Both books claim 26 molecules of oxygen needed for
stearic acid oxidation and 6 molecules for glucose. 3 molecule of glucose ( 18 carbon)
use 18 molecule of oxygen. Stearic acid uses more oxygen than glucose per carbon.

Biochemistry
Jeremy M. Berg (Author), John L. Tymoczko (Author), Lubert Stryer (Author)

Page 14 and 15
http://www.uccs.edu/~sbraunsa/Images/48 ... ab-2pp.pdf

My understanding and view is that glucose needs less oxygen than fat per ATP molecule production and the body shifts from fat burning to glucose burning the higher the intensity of exercise.
If anyone disagrees, I'd like to see their references for supporting their alternative view.
The problem is many text books differ on the ultimate ATP yield between fat vs sugar.
Then you also get many different forms of fatty acids, further complicating the issue.
It seems the general consensus view is that the Net gain of ATP from fatty acids is 14n - 6 ATP
so for a 16C fatty acid like palmitic acid the net gain is around 106 ATP vs 30 for glucose
http://pharmaxchange.info/press/2013/10 ... tty-acids/
But I think more important is the amount of CO2 produced because ultimately you can only exchange O2 for CO2 produced via the lungs. It is here where as Ray Peat often emphasizes that sugar/glucose produce far more CO2 than fat burning does.
consider the 2 following equations, glucose vs palmitic acid
Glucose:
C6H12O6 + 6O2 >> 12H2O + 6 CO2 + 30 ATP + heat
Palmitic acid (Sat fat)
C16H32O2 + 23 O2 >> 16H2O + 16 CO2 + 106 ATP + heat

So for every molecule ATP produced, glucose needs 5 molecules of O2 and fat 4.6 molecules of O2 in an environment of no O2 limitation. However, since the fat only produces 16 molecules of CO2, only that amount can be exchanged via the lungs and carried by the hemoglobin in the blood. The glucose is therefore 16/23 x 5/4.6 or about 25% more efficient.
edit: the above should rather read

So for every molecule of O2 used, 5 molecules of ATP are produced burning glucose and fat produces only 4.6 molecules of ATP per molecule of O2 used in an environment of no O2 limitation. However, since the fat only produces 16 molecules of CO2, only that amount can be exchanged via the lungs and carried by the hemoglobin in the blood. The glucose is therefore 16/23 x 4.6/5 or about 36% more efficient.


The rate of ATP production during aerobic metabolism is not something I have studied or seen discussed yet and I am not sure if there is really a difference other than the limit of oxygen supply.

The wasting of glucose by creating lactic acid you talk about happens when the need for ATP exceeds the speed of (rate of) supply that can be created by complete aerobic respiration alone either via oxygen limitations or other defects.

Anyway, that is how I understand it. Anyone is free to disagree and provide references for their alternative views.

 

[pboy]

that's what both of us already said, but ok...appreciate the details, a nice write up

 

[Such_Saturation]

Your doubts are not clear to me. Fat is always entering the cell in some amount.

If that's to what I wrote before. It's hard to give personal advice. As said it's all matter of context and personal state and the goal someone has in mind.
The 'some amount' is true but depends on concentrations. Sometimes if you want to change things, a change in concentration is needed to induce changes. Also if you can't oxidize this will alter your concentrations compared to other peoples hence need less for the same concentrations..

Pone's question is not clear, I don't understand.

Many web sites make the claim that burning glucose will produce 30 to 36 ATP, whereas burning fat will produce more than 130 ATP. You see the claim constantly on ketogenic web sites that burning fat is far far far more efficient in production of ATP than burning glucose. Typical page is this one:

http://www.begin2dig.com/2009/08/respec ... rning.html

So I don't understand why Peat obsesses about the release of free fatty acids during exercise and how he seems to imply that this lowers the amount of energy that the body can produce in aerobic metabolism.

<<Free fatty acids suppress mitochondrial respiration (Kamikawa and Yamazaki, 1981), leading to increased glycolysis (producing lactic acid) to maintain cellular energy. The suppression of mitochondrial respiration increases the production of toxic free radicals, and the decreased carbon dioxide makes the proteins more susceptible to attack by free radicals. The lactate produced under the influence of excessive fat metabolism stimulates the release of endorphins, which are lipolytic, releasing more free fatty acids from the tissues. Acting through cytokines such as interleukin-6, lactate shifts the balance toward the catabolic hormones, leading to tissue wasting.

Lactic acid itself, and the longer chain fatty acids, inhibit the regulatory enzyme pyruvate dehydrogenase (which is activated by insulin), reducing the oxidative production of energy. Drugs to activate this enzyme are being studied by the pharmaceutical industry as treatments for diabetes and cancer (for example, DCA, dichloroacetate).>>

(Peat R., 2013)


for SAFarmer:

<<When non-diabetic apes were given insulin treatments, they developed some of the same "complications of diabetes" that are seen in humans, and antibodies to insulin were found in their retinas, suggesting that some "complications of diabetes" were complications of insulin treatment. Patients were seldom well informed of the arguments against the use of insulin, but the justification for the new genetically engineered human insulin is precisely that it avoids immunological damage.
Insulin was introduced into medicine in the 1920s. According to the Britannica Book of the Year for 1947, page 265, "Mortality from diabetes in 1920 in the United States was 16.0 per 100,000, 14,062 deaths, but in 1944, it was 26.4 per 100,000, 34,948 deaths.">>

(Peat R., 2006)

 

[Suikerbuik]

Which Peat article best summarizes these ideas?

And - the bottom line - what do we do to prevent all of this from happening? Surely he isn't saying eat sugar without any fat?

Enjoy your fat, but limit lipolysis. Peat is not about blocking beta-oxidation (fat oxidation) and it isn't supposed to be low fat, although some may do better on low fat.

You can find references in Peats articles. The functionalps site summarizes things pretty well too. And there's numerous articles on the web, pubmed for example.

 

[SAFarmer]

for SAFarmer:

<<When non-diabetic apes were given insulin treatments, they developed some of the same "complications of diabetes" that are seen in humans, and antibodies to insulin were found in their retinas, suggesting that some "complications of diabetes" were complications of insulin treatment. Patients were seldom well informed of the arguments against the use of insulin, but the justification for the new genetically engineered human insulin is precisely that it avoids immunological damage.
Insulin was introduced into medicine in the 1920s. According to the Britannica Book of the Year for 1947, page 265, "Mortality from diabetes in 1920 in the United States was 16.0 per 100,000, 14,062 deaths, but in 1944, it was 26.4 per 100,000, 34,948 deaths.">>

(Peat R., 2006)

Ummm, yes, your point ?

If you give insulin to non diabetic apes, they probably would develop hypoglycemia, and many of the complications seen in humans are also due to hypoglycemia ...

 

[Such_Saturation]

My point was to courteously provide the part where Ray Peat has written that he regards insulin as the culprit in what are normally considered symptoms of diabetes, which is what you had asked.