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How does the body fuel itself?
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tennisdude2004 wrote: »johnslater461 wrote: »tennisdude2004 wrote: »tennisdude2004 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
Sorta nothing like your example.
To claim something is exclusive is claiming it is the only source and as we all know that is incorrect.
The brain functions just as optimal with a mix of ketones, glucose and lactate.
If anything studies have suggested that during exercise the brains preferred fuel is lactate.
That is why there are so many low carb and keto athletes.. oh wait..
Also, most vitamins and minerals are generally acquired by plant based source.. which are carbs.
Are you suggesting there are not many low carb athletes?
There aren't. There are a trivial number of vocal ketoevangalist amateur athletes, but the overwhelming majority of professional athletes are not low carb.
I don't disagree that a majority of athletes are not low carb, but to suggest there aren't many professional athletes that eat low carb is extremely disingenuous.
There are athletes at the top of their field, who are house hold names within most sports that have chosen a low carb model of eating.
Tennis - Novak Djokovic switched to low carb before he reached his pinnicle of No 1 in the world.
His Diet through the DayDjokovic benefits from consuming 5 healthy-portioned meals in a day instead of 3 heavy ones and fills the mid-morning and post-lunch snack slots with gluten-free versions of toast and crackers, fruits and nuts and some almond butter. Lunch and dinner are protein-packed meals including white meat (like chicken), fish, gluten-free pasta and lots of vegetables.
Doesn't sound very low carb to me
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Ask Novak Djokovic, he got to no1 in the world and held the spot for several years following a low carb diet model.14
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tennisdude2004 wrote: »Ask Novak Djokovic, he got to no1 in the world and held the spot for several years following a low carb diet model.
Day One
Breakfast Water first thing out of bed; two tablespoons of honey; muesli (including organic gluten-free rolled oats, cranberries, raisins, pumpkin or sunflower seeds and almonds)
Mid-morning snack (if needed): Gluten-free bread or crackers with avocado and tuna
Lunch Mixed-greens salad, gluten-free pasta primavera (including rice pasta, summer squash, courgettes, asparagus, sun-dried tomatoes and optional vegan cheese)
Mid-afternoon snack Apple with cashew butter; melon
Dinner Kale caesar salad (kale, fennel, quinoa and pine nuts) plus dressing (including anchovies or sardines); minestrone soup; salmon fillets (skin on) with roasted tomatoes and marinade
https://www.independent.co.uk/sport/tennis/revealed-the-diet-that-saved-novak-djokovic-8775333.html
Gluten free is not the same as low carb16 -
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_race14 -
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_race
Exactly, as do almost all athletes who follow a low carb training regimen. A fact that seems to be conveniently overlooked when the ketovangelists are preaching unencumbered by facts.14 -
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'm not saying that having available glucose is bad, or it wasn't crucial to our ancestors when they needed to escape a bear, but I disagree with the blanket application of the term preferred without taking into consideration the foods and macronutrients that the body is accustomed to.
It is only red blood cells that are obligate glucose users. Everything else has great metabolic flexibility.21 -
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.
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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_race
Carb loading for competition or training does not mean one does not follow a ketogenic diet. That would be using a TKD. Carbs are eaten around exercise. They may not even leave ketosis.
There was a member a while back who was ketogenic - he tested - even though he would eat around 200 g carbs around his 4-6 hour bike rides. He was just doing what worked for him to make the most of his activity.... While following a ketogenic diet. He might have even had extra protein around his exercise, but that doesn't mean he followed a really high protein diet.
Peter Attia called carbs a performance enhancing substance. That doesn't mean you need to rely on them for all of your fuel needs.I notice that none of these are marathon runners. I wonder how good ketosis is at fuelling sustained endurance.
TBH, anecdotal evidence seems to support the best success with athletics and ketogenic diets in endurance events. That one power walker study that stated otherwise which seems to be quoted frequently seems to be an anomaly. My guess is that they did not allow enough fat adaptation time. For more explosive sports, carb loading may improve performance a bit. So will caffeine and steroids. For the average Joe, none are crucial.
Tim Noakes is a doctor and well respected running guru. He wrote The Lore of Running, a bible for many endurance runners, and (I believe) he even helped invent a glucose gel (Gu?). He did a complete 180 many years years ago and now teaches the opposite.12 -
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.20 -
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.
17 -
This is going nowhere. I'm off to enjoy Sunday.8
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This discussion has been closed.
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