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How does the body fuel itself?
Replies
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johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
Prefer is an odd word to use when dealing with body systems. Muscles don't have a personal liking for glucose. They adapt to whatever fuel us regularly used and get used to using that fuel primarily... It doesn't mean they aren't "allowed" to use a different fuel source at times.
Is this a contest to see how far you can twist logic in an analogy to make it confirm your bias? If so, you win!!21 -
johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
The former.
The (non-diabetic)body is perfectly capable of keeping BG steady during rest, so the fact that muscles will primarily use glucose during bursts of energy likely has little to do with keeping BG steadyPrefer is an odd word to use when dealing with body systems.
Yet you had no problem with the term before your misuse of it was pointed out.
False.Muscles don't have a personal liking for glucose. They adapt to whatever fuel us regularly used and get used to using that fuel primarily... It doesn't mean they aren't "allowed" to use a different fuel source at times.
Muscle tissue will use fat and ketones during bursts of energy only when glucose is unavailable.
Same goes for the brain, which still needs glucose to function, to the point where the body will cannibalize muscle to provide it.
For the brain to function, glucose is both a necessary and sufficient fuel source.
Fat and ketones are neither.
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"johnslater461 wrote: »johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
The former.
The (non-diabetic)body is perfectly capable of keeping BG steady during rest, so the fact that muscles will primarily use glucose during bursts of energy likely has little to do with keeping BG steadyPrefer is an odd word to use when dealing with body systems.
Yet you had no problem with the term before your misuse of it was pointed out.
Well, no. I don't believe I was the one who first introduced that term. I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
False.Muscles don't have a personal liking for glucose. They adapt to whatever fuel us regularly used and get used to using that fuel primarily... It doesn't mean they aren't "allowed" to use a different fuel source at times.
Muscle tissue will use fat and ketones during bursts of energy only when glucose is unavailable.
We only use bursts of adrenaline when we need it too. That doesn't mean it needs to be around at higher levels all of the time.
And muscles still use glucose for bursts of energy when in ketosis. That's what glycogen is for.Same goes for the brain, which still needs glucose to function, to the point where the body will cannibalize muscle to provide it.
For the brain to function, glucose is both a necessary and sufficient fuel source.
Fat and ketones are neither.
If you look closely, you'll see I never said glucose is not a necessary or sufficient fuel for the brain. I said that the primary fuel is based upon what you eat.
And the body only "canabalizes" muscles if one does not eat protein. Plus those that are fat adapted tend to use the glycerol backbone of fatty acids to complete gluconeogenesis. I'm sure you know that.
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I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Which completely ignores the fact that in the presence of both fuels, the brain utilizes glucose preferentially. Talk about confirmation bias!!17 -
I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Which completely ignores the fact that in the presence of both fuels, the brain utilizes glucose preferentially. Talk about confirmation bias!!
You didn't read my links... And what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel. If you eat a diet higher in carbs and fats (and protein of course) the body will use the glucose first for health and safety reasons. Mixed fuel sources is considered carbs for fuel unless one wants really high BG, or to go to the extra trouble of storing glucose as fat when dietary fat is simpler to store.
A sandwich has more glucose than the 4 g maintained in the blood at any given time. The body uses the glucose first to help regulate BG levels. Plus the body is used to using glucose as its fuel if that's what you feed it.
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"johnslater461 wrote: »johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
The former.
The (non-diabetic)body is perfectly capable of keeping BG steady during rest, so the fact that muscles will primarily use glucose during bursts of energy likely has little to do with keeping BG steadyPrefer is an odd word to use when dealing with body systems.
Yet you had no problem with the term before your misuse of it was pointed out.
Well, no. I don't believe I was the one who first introduced that term. I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Completely and utterly false. If glucose is available, the brain will use it exclusively. It will use ketones ONLY if there isn't sufficient glucose available, no matter how long it's been "used to" using ketones.
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I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Which completely ignores the fact that in the presence of both fuels, the brain utilizes glucose preferentially. Talk about confirmation bias!!
You just made my point. Whatever fuel the body is used to using is the preferred fuel. If you eat a diet higher in carbs and fats (and protein of course) the body will use the glucose first for health and safety reasons.
Nonsense. The body will use its preferred fuel based on efficiency. Preferred fuel doesn't change based on availability.
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johnslater461 wrote: »tennisdude2004 wrote: »
Are you talking about Zach Bitter?
Guess what? He still carb loads for races
https://zachbitter.com/blog/2017/07/17/periodizing_nutrition_part_4_-_taper_and_racejohnslater461 wrote: »tennisdude2004 wrote: »
Are you talking about Zach Bitter?
Guess what? He still carb loads for races
https://zachbitter.com/blog/2017/07/17/periodizing_nutrition_part_4_-_taper_and_race
It’s still a low carb diet model based on his CICO.
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This is going nowhere. I'm off to enjoy Sunday.8
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I'll take the preferred method ( glucose) any day!
You know the saying- sometimes people succeed despite what they do , not because of what they do.13 -
johnslater461 wrote: »"johnslater461 wrote: »johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
The former.
The (non-diabetic)body is perfectly capable of keeping BG steady during rest, so the fact that muscles will primarily use glucose during bursts of energy likely has little to do with keeping BG steadyPrefer is an odd word to use when dealing with body systems.
Yet you had no problem with the term before your misuse of it was pointed out.
Well, no. I don't believe I was the one who first introduced that term. I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Completely and utterly false. If glucose is available, the brain will use it exclusively. It will use ketones ONLY if there isn't sufficient glucose available, no matter how long it's been "used to" using ketones.
Now there’s that word exclusively again!
So let me get this straight John, you are claiming that an athlete on a high carb diet and fully carb loaded, whilst performing at maximum effort will not be using any other fuel for their brain during this period?
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tennisdude2004 wrote: »johnslater461 wrote: »"johnslater461 wrote: »johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
The former.
The (non-diabetic)body is perfectly capable of keeping BG steady during rest, so the fact that muscles will primarily use glucose during bursts of energy likely has little to do with keeping BG steadyPrefer is an odd word to use when dealing with body systems.
Yet you had no problem with the term before your misuse of it was pointed out.
Well, no. I don't believe I was the one who first introduced that term. I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Completely and utterly false. If glucose is available, the brain will use it exclusively. It will use ketones ONLY if there isn't sufficient glucose available, no matter how long it's been "used to" using ketones.
Now there’s that word exclusively again!
So let me get this straight John, you are claiming that an athlete on a high carb diet and fully carb loaded, whilst performing at maximum effort will not be using any other fuel for their brain during this period?
Correct.
Brain. Glucose is virtually the sole fuel for the human brain, except during prolonged starvation. The brain lacks fuel stores and hence requires a continuous supply of glucose. It consumes about 120 g daily, which corresponds to an energy input of about 420 kcal (1760 kJ), accounting for some 60% of the utilization of glucose by the whole body in the resting state. Much of the energy, estimates suggest from 60% to 70%, is used to power transport mechanisms that maintain the Na+-K+ membrane potential required for the transmission of the nerve impulses. The brain must also synthesize neurotransmitters and their receptors to propagate nerve impulses. Overall, glucose metabolism remains unchanged during mental activity, although local increases are detected when a subject performs certain tasks.
Glucose is transported into brain cells by the glucose transporter GLUT3. This transporter has a low value of KM for glucose (1.6 mM), which means that it is saturated under most conditions. Thus, the brain is usually provided with a constant supply of glucose. Noninvasive 13C nuclear magnetic resonance measurements have shown that the concentration of glucose in the brain is about 1 mM when the plasma level is 4.7 mM (84.7 mg/dl), a normal value. Glycolysis slows down when the glucose level approaches the KM value of hexokinase (~50 μM), the enzyme that traps glucose in the cell (Section 16.1.1). This danger point is reached when the plasma-glucose level drops below about 2.2 mM (39.6 mg/dl) and thus approaches the KM value of GLUT3.
Fatty acids do not serve as fuel for the brain, because they are bound to albumin in plasma and so do not traverse the blood-brain barrier. In starvation, ketone bodies generated by the liver partly replace glucose as fuel for the brain.
https://www.ncbi.nlm.nih.gov/books/NBK22436
Under normal circumstances, that is, ample glucose and few ketone bodies in the blood, the brain apparently does not oxidize ketones in any significant amounts. In prolonged starvation, the carbohydrate stores of the body are exhausted and the rate of gluconeogenesis is insufficient to provide glucose fast enough to meet the requirements of the brain; blood ketone concentrations rise as a result of the rapid fat catabolism. The brain then apparently turns to the ketone bodies as the source of its energy supply.
https://www.ncbi.nlm.nih.gov/books/NBK28048/18 -
Here's my analogy:
You have a car that's engineered and built to run on premium gasoline.
There's a gas shortage, and the only thing available at the pumps is the cheap crap, so you switch to that instead.
Will your car run?
Of course it will.
Will it run at peak efficiency and performance?
Not a chance.14 -
snickerscharlie wrote: »Here's my analogy:
You have a car that's engineered and built to run on premium gasoline.
There's a gas shortage, and the only thing available at the pumps is the cheap crap, so you switch to that instead.
Will your car run?
Of course it will.
Will it run at peak efficiency and performance?
Not a chance.
Do you have scientific evidence that the brain operates less optimally on a fuel mixture of glucose, ketones and lactate, or are you just stating opinion?
13 -
tennisdude2004 wrote: »snickerscharlie wrote: »Here's my analogy:
You have a car that's engineered and built to run on premium gasoline.
There's a gas shortage, and the only thing available at the pumps is the cheap crap, so you switch to that instead.
Will your car run?
Of course it will.
Will it run at peak efficiency and performance?
Not a chance.
Do you have scientific evidence that the brain operates less optimally on a fuel mixture of glucose, ketones and lactate, or are you just stating opinion?
Moot point, no evidence necessary. If glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.12 -
johnslater461 wrote: »tennisdude2004 wrote: »johnslater461 wrote: »"johnslater461 wrote: »johnslater461 wrote: »tennisdude2004 wrote: »pinggolfer96 wrote: »the brain and body's preferred source of energy IS glucose though. our body has to create ketones to run sufficiently on a low carb diet.
Preferred and exclusive are two totally different things!
Sorta like essential vs optimal..
But glucose is definitely preferred. But like all things with our bodies, they have the ability to survive in varies conditions.
OP, I'd add some more sodium and potassium. That could help
Glucose is the preferred fuel when carbs/glucose is the primary fuel. When fat is the primary fuel, fat and ketones is preferred.
Ketones are a starvation and glucose deprived response. So the brains will prefer to run off of glucose as much as it can. It doesn't even consider many other parts of the body can only run on glucose, which is why our body can convert fatty acids and amino acids into glucose.
Overall, the body runs on fats and carbs. And it sucks trying to use protein.
You could just as easily say that glucose causes a ketone suppressing response because the body needs to move glucose out of the blood in order to keep BG at safe levels - around a teaspoon of sugar. Basically, it's easier to get the body to stop ketone production than it is to get a body to stop eating more carbs than it needs at that moment.
Or consider that people who have been eating very low carb for some time appear to have what some would call temporary physiological Insulin resistance. For a couple of days the body needs more insulin to convince it to take in more glucose. Once it adapts to higher carb levels again, the needs for more insulin disappears. This would be true for even the most metabolically healthy individual who is fat adapted.
Likewise, it will take someone switching to keto a few days for their body to get more used to using fat and relying on ketones. The preferred fuel type depends on the usual fuel source.
I see you still don't grasp the meaning of the word "prefer"
If someone likes both steak and lobster, but will always choose the lobster when given a choice, he prefers lobster to steak.
If there is no lobster available, and he orders the steak, he hasn't changed his preference.
A house is on fire so it is doused with water. Does the owner prefer a soggy house?
Muscle uses glucose because a person eats 40g of carbs every 2-4 hours. Does it prefer glucose or is the body trying to keep BG steady?
The former.
The (non-diabetic)body is perfectly capable of keeping BG steady during rest, so the fact that muscles will primarily use glucose during bursts of energy likely has little to do with keeping BG steadyPrefer is an odd word to use when dealing with body systems.
Yet you had no problem with the term before your misuse of it was pointed out.
Well, no. I don't believe I was the one who first introduced that term. I entered the conversation to try to make it clearer that the brain does not just run on glucose and that its fuel use (preference) is based solely on what it is used to.
Completely and utterly false. If glucose is available, the brain will use it exclusively. It will use ketones ONLY if there isn't sufficient glucose available, no matter how long it's been "used to" using ketones.
Now there’s that word exclusively again!
So let me get this straight John, you are claiming that an athlete on a high carb diet and fully carb loaded, whilst performing at maximum effort will not be using any other fuel for their brain during this period?
Correct.
Brain. Glucose is virtually the sole fuel for the human brain, except during prolonged starvation. The brain lacks fuel stores and hence requires a continuous supply of glucose. It consumes about 120 g daily, which corresponds to an energy input of about 420 kcal (1760 kJ), accounting for some 60% of the utilization of glucose by the whole body in the resting state. Much of the energy, estimates suggest from 60% to 70%, is used to power transport mechanisms that maintain the Na+-K+ membrane potential required for the transmission of the nerve impulses. The brain must also synthesize neurotransmitters and their receptors to propagate nerve impulses. Overall, glucose metabolism remains unchanged during mental activity, although local increases are detected when a subject performs certain tasks.
Glucose is transported into brain cells by the glucose transporter GLUT3. This transporter has a low value of KM for glucose (1.6 mM), which means that it is saturated under most conditions. Thus, the brain is usually provided with a constant supply of glucose. Noninvasive 13C nuclear magnetic resonance measurements have shown that the concentration of glucose in the brain is about 1 mM when the plasma level is 4.7 mM (84.7 mg/dl), a normal value. Glycolysis slows down when the glucose level approaches the KM value of hexokinase (~50 μM), the enzyme that traps glucose in the cell (Section 16.1.1). This danger point is reached when the plasma-glucose level drops below about 2.2 mM (39.6 mg/dl) and thus approaches the KM value of GLUT3.
Fatty acids do not serve as fuel for the brain, because they are bound to albumin in plasma and so do not traverse the blood-brain barrier. In starvation, ketone bodies generated by the liver partly replace glucose as fuel for the brain.
https://www.ncbi.nlm.nih.gov/books/NBK22436
Under normal circumstances, that is, ample glucose and few ketone bodies in the blood, the brain apparently does not oxidize ketones in any significant amounts. In prolonged starvation, the carbohydrate stores of the body are exhausted and the rate of gluconeogenesis is insufficient to provide glucose fast enough to meet the requirements of the brain; blood ketone concentrations rise as a result of the rapid fat catabolism. The brain then apparently turns to the ketone bodies as the source of its energy supply.
https://www.ncbi.nlm.nih.gov/books/NBK28048/
Sorry John, it would appear actual science disagrees with you.
https://www.fasebj.org/doi/abs/10.1096/fj.08-106104
http://www.jneurosci.org/content/31/20/7477
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3247678/?tool=pubmed
https://medicalxpress.com/news/2010-11-lactate-shuttle-fuel-brain.html21 -
tennisdude2004 wrote: »snickerscharlie wrote: »Here's my analogy:
You have a car that's engineered and built to run on premium gasoline.
There's a gas shortage, and the only thing available at the pumps is the cheap crap, so you switch to that instead.
Will your car run?
Of course it will.
Will it run at peak efficiency and performance?
Not a chance.
Do you have scientific evidence that the brain operates less optimally on a fuel mixture of glucose, ketones and lactate, or are you just stating opinion?
Moot point, no evidence necessary. If glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
Again with the word exclusively!
I think what you mean is when glucose is readily available the brain will use it, not exclusively, but as virtually the sole fuel unless of course you are performing vigorous exercise, when the brain will also draw upon lactate.
But of course the brain doesn't need to have solely glucose available to operate optimally. And the fact we can naturally produce adequate amounts makes life very easy.15 -
No, I basically did not.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not the one the body is used to using. it is the one the body prioritizes.
What you said is a misinterpretation of physiology at best and a blatant misrepresentation at worst.
This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
10 -
edit function seems to be malfunctioning.4
-
No, I basically did not.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.18 -
No, I basically did not.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not the one the body is used to using. it is the one the body prioritizes.
What you said is a misinterpretation of physiology at best and a blatant misrepresentation at worst.
This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
To keep using the term exclusively is a misinterpretation of physiology at best and a blatant misrepresentation at worst.
I can only assume there are a handful of people out there that don’t quite understand the meaning of the term exclusively!
16 -
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
Also, having huge carb refeeds prior to an event is more CKD.
6 -
This response fit in both threads so I am quoting it here:The glory of fat is that it is a concentrated food source that takes a complicated round of metabolic processes to convert it to glucose. It takes hours.
This is what makes fat consumption good for the brain. It’s a steady source of calories even hours after eating.
Undiagnosed diabetes can also result in brain fog.0 -
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
I sort of agree. Basal glucose is always available and it can more than meets our basic needs. You can see that in some people who eat keto, train keto, and still have a bit high fasting glucose the next day. I just meant to point out that when fat or ketones are used in a fat adapted individual , it's not because you've run out of glucose. Eventually fat and ketones is a well used fuel for the body.
And when did glucose become the primary fuel source for humans? I'm not really asking you, just wondering in general. Is it just because of what north Americans mostly eat for fuel? I think infants and exclusively breast fed babies are mildly ketogenic, aren't they?
IDK, I'm still of the opinion that whatever fuel your body is adapted to is the primary and "preferred" fuel for that individual. I don't think I'm stressing my body out by having it rely on fat and ketones for most fuel (even though glucose is present), nor do I think your body is unhealthy for relying on glucose most of the time (even though fat is present).Also, having huge carb refeeds prior to an event is more CKD.
Huge carb refeeds (with depleted glycogen between carb loads) is definitely more CKD. TKD is typically used more by endurance athletes - a topping off of glycogen as it were - about 30 minutes before activity. CKD is more often used for lifters trying to make gains... As I understand it.
15 -
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
I sort of agree. Basal glucose is always available and it can more than meets our basic needs. You can see that in some people who eat keto, train keto, and still have a bit high fasting glucose the next day. I just meant to point out that when fat or ketones are used in a fat adapted individual , it's not because you've run out of glucose. Eventually fat and ketones is a well used fuel for the body.
And when did glucose become the primary fuel source for humans? I'm not really asking you, just wondering in general. Is it just because of what north Americans mostly eat for fuel? I think infants and exclusively breast fed babies are mildly ketogenic, aren't they?
IDK, I'm still of the opinion that whatever fuel your body is adapted to is the primary and "preferred" fuel for that individual. I don't think I'm stressing my body out by having it rely on fat and ketones for most fuel (even though glucose is present), nor do I think your body is unhealthy for relying on glucose most of the time (even though fat is present).Also, having huge carb refeeds prior to an event is more CKD.
Huge carb refeeds (with depleted glycogen between carb loads) is definitely more CKD. TKD is typically used more by endurance athletes - a topping off of glycogen as it were - about 30 minutes before activity. CKD is more often used for lifters trying to make gains... As I understand it.
Fat and carbs are both primary fuels... fats are used more often when you are doing daily activities and oxygen requirements aren't as high; carbs when used more (either post meal) or when there are greater oxygen requirements.
But ketones are not a primary source of fuel (which I guess is the argument). Ketones are a derivative of starvation, very low carb and extreme endurance active (as glycogen gets depleted). In the event that a person doesn't consume enough glucose, a body will convert fatty acids (~40%) and amino acids (~60%) into glucose to address those basal needs; IIRC, things like the circulatory system, heart, and a few other organs require glucose and can't utilize ketones.
Like all humans, babies will produce ketones, especially over night. But most peoples get a good amount of carbs. Carbs are a huge driver for development. In a single serving of my daughters formula, it's 2g of protein, 5g of fat, 10g carbs. As you know carbs cause lipogenesis which unlocks the cells to take in nutrients.
CKD vs TKD, it would depend on how the person is using it. If they are merely timing nutrients around a workout, or an event, than it would be a TKD diet. But if they are incorporating refeeds to increase glycogen capacity, improve insulin sensitivity, and drive better recovery and muscle development, than it would be CKD. I guess I would have to read more about his diet to see which method is used. Because with endurance athletes, glycogen depletion will occur, especially since they aren't just running at one constant speed in the "fat burning" zone. There will be changes in terrain which will require greater oxygen, which driven glycogen needs (since carbs convert to ATP easier). And since glycogen can be replenished in about 24 hours (based on how often you consume carbs and if you eat the appropriate amount; generally 100 to 150g every few hours until you hit @ bw in kg * 16), it's no uncommon to see 2 to 3 days of refeed prior to the event, consumption of glucose/fructose and maybe some proteins prior to events.8 -
PaulChasinDreams wrote: »
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
I sort of agree. Basal glucose is always available and it can more than meets our basic needs. You can see that in some people who eat keto, train keto, and still have a bit high fasting glucose the next day. I just meant to point out that when fat or ketones are used in a fat adapted individual , it's not because you've run out of glucose. Eventually fat and ketones is a well used fuel for the body.
And when did glucose become the primary fuel source for humans? I'm not really asking you, just wondering in general. Is it just because of what north Americans mostly eat for fuel? I think infants and exclusively breast fed babies are mildly ketogenic, aren't they?
IDK, I'm still of the opinion that whatever fuel your body is adapted to is the primary and "preferred" fuel for that individual. I don't think I'm stressing my body out by having it rely on fat and ketones for most fuel (even though glucose is present), nor do I think your body is unhealthy for relying on glucose most of the time (even though fat is present).Also, having huge carb refeeds prior to an event is more CKD.
Huge carb refeeds (with depleted glycogen between carb loads) is definitely more CKD. TKD is typically used more by endurance athletes - a topping off of glycogen as it were - about 30 minutes before activity. CKD is more often used for lifters trying to make gains... As I understand it.
This is the most accurate post on this thread. And other posts here by nvmomketo and tennisdude2004. The other attempts of rebuttal by the anti keto posse is just more typical glucose/cico/anti keto brainwashing attempts and old, weak, disproved theories. Get with the times and new proven science lol.... so obvious it's laughable some of the arguments people try to use against it here. Glucose is exactly that...one energy source that a lot of people's body uses cause that is what most people stuff themselves with all day long. Do you think that was humans main energy source was back in the day when you all didn't have such easy access to the garbage carbs you are feeding yourselves with now days. Do you think when humans ate mostly fat and protein their bodies metabolisms ran the same as your high carb metabolism does?? No, give your heads a shake. Common sense and common knowledge. Keeping your heads in the sands won't get rid of the truth. Give your body another source of energy/nutrition and that's what it uses for the energy. Proven by millions of low carb/keto eating people all over the world every day of the year. Time to get over it forum posse bullies lol. Glad to see so many people on this forum showing up from all over the world learning about and living keto and how glucose has been killing people all over the world in astronomically rising numbers every day. Type 2 Diabetes has never been higher and not just in adults and the elderly anymore; children and teens with it are increasing in crazy numbers like never before.
And 'there's no high performance athletes that are low carb' LOL!!! Do you not read, or do you not have a computer?
Rather than be the one to ask for sources, irony of your insults, etc....etc...etc...
I've become more interested in....how in the hell were you able to edit your post 6 hours after initially posting it?
Editing to verify that indeed, mine says we have an hour.11 -
PaulChasinDreams wrote: »
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
I sort of agree. Basal glucose is always available and it can more than meets our basic needs. You can see that in some people who eat keto, train keto, and still have a bit high fasting glucose the next day. I just meant to point out that when fat or ketones are used in a fat adapted individual , it's not because you've run out of glucose. Eventually fat and ketones is a well used fuel for the body.
And when did glucose become the primary fuel source for humans? I'm not really asking you, just wondering in general. Is it just because of what north Americans mostly eat for fuel? I think infants and exclusively breast fed babies are mildly ketogenic, aren't they?
IDK, I'm still of the opinion that whatever fuel your body is adapted to is the primary and "preferred" fuel for that individual. I don't think I'm stressing my body out by having it rely on fat and ketones for most fuel (even though glucose is present), nor do I think your body is unhealthy for relying on glucose most of the time (even though fat is present).Also, having huge carb refeeds prior to an event is more CKD.
Huge carb refeeds (with depleted glycogen between carb loads) is definitely more CKD. TKD is typically used more by endurance athletes - a topping off of glycogen as it were - about 30 minutes before activity. CKD is more often used for lifters trying to make gains... As I understand it.
This is the most accurate post on this thread. And other posts here by nvmomketo and tennisdude2004. The other attempts of rebuttal by the anti keto posse is just more typical glucose/cico/anti keto brainwashing attempts and old, weak, disproved theories. Get with the times and new proven science lol.... so obvious it's laughable some of the arguments people try to use against it here. Glucose is exactly that...one energy source that a lot of people's body uses cause that is what most people stuff themselves with all day long. Do you think that was humans main energy source was back in the day when you all didn't have such easy access to the garbage carbs you are feeding yourselves with now days. Do you think when humans ate mostly fat and protein their bodies metabolisms ran the same as your high carb metabolism does?? No, give your heads a shake. Common sense and common knowledge. Keeping your heads in the sands won't get rid of the truth. Give your body another source of energy/nutrition and that's what it uses for the energy. Proven by millions of low carb/keto eating people all over the world every day of the year. Time to get over it forum posse bullies lol. Glad to see so many people on this forum showing up from all over the world learning about and living keto and how glucose has been killing people all over the world in astronomically rising numbers every day. Type 2 Diabetes has never been higher and not just in adults and the elderly anymore; children and teens with it are increasing in crazy numbers like never before.
And 'there's no high performance athletes that are low carb' LOL!!! Do you not read, or do you not have a computer?
Rather than be the one to ask for sources, irony of your insults, etc....etc...etc...
I've become more interested in....how in the hell were you able to edit your post 6 hours after initially posting it?
Editing to verify that indeed, mine says we have an hour.
More likely case is that it wasn't he who edited it.3 -
PaulChasinDreams wrote: »
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
I sort of agree. Basal glucose is always available and it can more than meets our basic needs. You can see that in some people who eat keto, train keto, and still have a bit high fasting glucose the next day. I just meant to point out that when fat or ketones are used in a fat adapted individual , it's not because you've run out of glucose. Eventually fat and ketones is a well used fuel for the body.
And when did glucose become the primary fuel source for humans? I'm not really asking you, just wondering in general. Is it just because of what north Americans mostly eat for fuel? I think infants and exclusively breast fed babies are mildly ketogenic, aren't they?
IDK, I'm still of the opinion that whatever fuel your body is adapted to is the primary and "preferred" fuel for that individual. I don't think I'm stressing my body out by having it rely on fat and ketones for most fuel (even though glucose is present), nor do I think your body is unhealthy for relying on glucose most of the time (even though fat is present).Also, having huge carb refeeds prior to an event is more CKD.
Huge carb refeeds (with depleted glycogen between carb loads) is definitely more CKD. TKD is typically used more by endurance athletes - a topping off of glycogen as it were - about 30 minutes before activity. CKD is more often used for lifters trying to make gains... As I understand it.
This is the most accurate post on this thread. And other posts here by nvmomketo and tennisdude2004. The other attempts of rebuttal by the anti keto posse is just more typical glucose/cico/anti keto brainwashing attempts and old, weak, disproved theories. Get with the times and new proven science lol.... so obvious it's laughable some of the arguments people try to use against it here. Glucose is exactly that...one energy source that a lot of people's body uses cause that is what most people stuff themselves with all day long. Do you think that was humans main energy source was back in the day when you all didn't have such easy access to the garbage carbs you are feeding yourselves with now days. Do you think when humans ate mostly fat and protein their bodies metabolisms ran the same as your high carb metabolism does?? No, give your heads a shake. Common sense and common knowledge. Keeping your heads in the sands won't get rid of the truth. Give your body another source of energy/nutrition and that's what it uses for the energy. Proven by millions of low carb/keto eating people all over the world every day of the year. Time to get over it forum posse bullies lol. Glad to see so many people on this forum showing up from all over the world learning about and living keto and how glucose has been killing people all over the world in astronomically rising numbers every day. Type 2 Diabetes has never been higher and not just in adults and the elderly anymore; children and teens with it are increasing in crazy numbers like never before.
And 'there's no high performance athletes that are low carb' LOL!!! Do you not read, or do you not have a computer?
There is a lot wrong with this post, but I will try to keep it simple for you since you obviously don't have an open mind about anything that might challenge your fairy tail views about keto. First, CICO is not a theory, it is fact. There is a reason it is called the law of thermodynamics and not a theory. Second, if anyone is brainwashed, it is those keto extremists who think that keto somehow defies the CICO equation. The number of people on this site who make that claim just baffles me. Keto is a valuable tool for some, because it helps them stay at a calorie deficit. That is the only reason that someone on a keto diet would lose weight. Third, you may hate carbs and view them as the devil but I think they are fantastic. They fuel my workouts and keep me satiated and despite what you may believe, they do not cause T2 diabetes. Being overweight or obese is definitely a cause though, which would be a good reason for people to make sure not to become that way by consuming too many calories.
You say to get with the times and the "new proven science" but there is absolutely nothing in your post to back your claims up. I'd love to see this "new proven science" that proves Keto is the end all be all. I'll save you some time though, that science just doesn't exist. Sure, their are numerous articles by crazy extremists and woo peddlers who are trying to make a quick buck with outlandish claims, but those articles only exist because the uneducated buy into these claims without doing any real research. Fourth, I didn't see anyone claim that there are no high performance athletes that are low carb, just that the overwhelming majority are not. Are you saying this is not true? Half a dozen athletes were thrown out as examples of low carb athletes, but the overwhelming majority are not, and there is a reason for that. You can laugh at others on this site who rebuke some of these outlandish keto claims, but you are laughing at the educated when you are most definitely not.29 -
No, I basically did not. For you to think that indicates that you either have severe reading comprehension problems or your confirmation bias has made you so delusional that you hear what you want to hear.what you said basically agrees with what I've said. Whatever fuel the body is used to using is the preferred fuel.
From AnvilHeadIf glucose is available, the brain will not utilize ketones. Glucose is the preferred fuel and if it's available, the brain will use it exclusively.
This is essentially what I said. If both fuel substrates are available, the brain will use glucose. Full stop.
That is defined as preferential. It's not what one the body is used to using. That is a misinterpretation of physiology at best and a blatant misrepresentation at worst. This is where some of you who are practitioners of keto go off the deep end and lose all credibility for what could be a potentially valuable dietary tool for some. You twist the truth. Or, lose site of it.
Glucose is ALWAYS available in the body for use. Full stop.
Despite the fact that glucose is always present in the body, the brain does not always rely on glucose for fuel even though both fuels are available... well, all three fuels if you consider what @tennisdude2004 pointed out. It comes down to the main fuel source - your body is not making ketones from dietary or body fat for brain fuel purposes when you are providing it with lots of glucose.
I do not have less glucose circulating in my body than someone else of the same size who uses carbs as their primary fuel; we might even have the same blood glucose measurements - mine's around a 5.3. My brain is not preferentially using glucose as its main fuel though.
The basic glucose needs of the body is around 130g, but the basic glucose needs of someone who is fat adapted is closer to 40g. Someone on a higher carb diet could stop eating, completely, and not die before fat adapted (or within a day) because the liver can make at least 130g of glucose a day... that should be enough for the brain.... but the brain is not always using glucose for it's fuel. Even though it is always available.
And no need to start being insulting. I understand what you are trying to say. I just don't agree with you. It's not that horrible of a thing. Really.
Basal glucose requirements are always available. And when depleted to that level, your body will use a secondary fuel source for your brain..... Its cheaper than the energy required to create more glucose through glucenogenesis.
Its the difference between minimal levels for optimal levels.
I sort of agree. Basal glucose is always available and it can more than meets our basic needs. You can see that in some people who eat keto, train keto, and still have a bit high fasting glucose the next day. I just meant to point out that when fat or ketones are used in a fat adapted individual , it's not because you've run out of glucose. Eventually fat and ketones is a well used fuel for the body.
And when did glucose become the primary fuel source for humans? I'm not really asking you, just wondering in general. Is it just because of what north Americans mostly eat for fuel? I think infants and exclusively breast fed babies are mildly ketogenic, aren't they?
IDK, I'm still of the opinion that whatever fuel your body is adapted to is the primary and "preferred" fuel for that individual. I don't think I'm stressing my body out by having it rely on fat and ketones for most fuel (even though glucose is present), nor do I think your body is unhealthy for relying on glucose most of the time (even though fat is present).Also, having huge carb refeeds prior to an event is more CKD.
Huge carb refeeds (with depleted glycogen between carb loads) is definitely more CKD. TKD is typically used more by endurance athletes - a topping off of glycogen as it were - about 30 minutes before activity. CKD is more often used for lifters trying to make gains... As I understand it.
Fat and carbs are both primary fuels... fats are used more often when you are doing daily activities and oxygen requirements aren't as high; carbs when used more (either post meal) or when there are greater oxygen requirements.
But ketones are not a primary source of fuel (which I guess is the argument). Ketones are a derivative of starvation, very low carb and extreme endurance active (as glycogen gets depleted). In the event that a person doesn't consume enough glucose, a body will convert fatty acids (~40%) and amino acids (~60%) into glucose to address those basal needs; IIRC, things like the circulatory system, heart, and a few other organs require glucose and can't utilize ketones.
Like all humans, babies will produce ketones, especially over night. But most peoples get a good amount of carbs. Carbs are a huge driver for development. In a single serving of my daughters formula, it's 2g of protein, 5g of fat, 10g carbs. As you know carbs cause lipogenesis which unlocks the cells to take in nutrients.
CKD vs TKD, it would depend on how the person is using it. If they are merely timing nutrients around a workout, or an event, than it would be a TKD diet. But if they are incorporating refeeds to increase glycogen capacity, improve insulin sensitivity, and drive better recovery and muscle development, than it would be CKD. I guess I would have to read more about his diet to see which method is used. Because with endurance athletes, glycogen depletion will occur, especially since they aren't just running at one constant speed in the "fat burning" zone. There will be changes in terrain which will require greater oxygen, which driven glycogen needs (since carbs convert to ATP easier). And since glycogen can be replenished in about 24 hours (based on how often you consume carbs and if you eat the appropriate amount; generally 100 to 150g every few hours until you hit @ bw in kg * 16), it's no uncommon to see 2 to 3 days of refeed prior to the event, consumption of glucose/fructose and maybe some proteins prior to events.
I think we understand each other. We just don't agree with each other completely. We're both coming from our own biases.
I agree that glucose and fat are primary fuels for the body (whereas glucose and ketones are used by the brain). I still think it depends on what you are eating (or how many carbs) that will determine which fuel is primary for an individual. It makes sense to me. You give a body fats and it gets really good at using fats. Give a body glucose and it gets good at using glucose.
I think glucose is called the primary fuel simply because that's what most people use. It's just a term that people assumed is correct, IMO. Often the next sentence added to that is how the brain will be starved for fuel if you consume less than 130g of glucose a day. We know that isn't right.
Absolutely, the body has a basal glucose need. Almost everything can use fats or ketones (as it's main fuel) too except RBC's. And there are other fuels that get used too. The heart , like the brain, also has a great affinity for lactate.
As to the issues of babies, I was not referring to formula but breast milk. The carbs in breast milk are a fair bit lower than formula. I think it's a little over a third carbs, but because of where they are developmentally, it appears exclusively BF'ed babies are often mildly ketogenic.
For CKD and TKD, I am not really sure where most low carbers who use them do so. I was under the impression that TKD was more common fro endurance athletes' training. They don't deplete glycogen like the more explosive sporting athletes do. Ketogeinc athletes (without carb loading CKD or TKD) have the same glycogen stores and speed of replenishment as higher carb athletes - I assume from gluconeogenesis using dietary fat and protein. CKD seems more common among lifters
If you do look into it and find anything to share, please do so. I'm always curious. Same goes for muscle recovery. I've actually read the opposite that muscle recovery appears a bit faster/easier on a ketogeinc diet. Muscle gains appear easier when more carbs are involved, definitely, but muscle recovery benefitting from carbs when one is fat adapted is not something I've ever read.
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