5 ms·

From the "recipe"[1]: This mechanism can also metabolize protein and fat, but the brain can only use Glucose for energy. In fact, the brain uses 25% of the bod

From the "recipe"[1]: This mechanism can also metabolize protein and fat, but the brain can only use Glucose for energy. In fact, the brain uses 25% of the body's glucose, though it accounts for only 2% of its weight. This would have me concerned if I were considering this. While 100% true, it neglects the entire ketone metabolic pathway[2], which the brain will use fine instead of glucose. If this something big like this has been missed (it's the foundation of many very-low carb diets, treatments for epilepsy and other brain disorders, etc), what subtle things have been missed? 1. http://robrhinehart.com/ http://robrhinehart.com/ 2. http://en.wikipedia.org/wiki/Ketone_bodies http://en.wikipedia.org/wiki/Ketone_bodies

deleted 14y ago
[deleted]
duskwuff 14y ago
Ketone metabolism works, but it's treated as if it's some kind of fallback -- it's only used when no other source of energy has been available for a few days. While it does seem like it's helpful in some situations, the way it's treated leads me to suspect it's probably harmful in the long run for otherwise healthy individuals.
- SoftwareMaven 14y ago
  I look at it just the opposite. Alcohol, in too much quantity, is essentially poisonous to your body, so it processes it out first. Glucose, in too much quantity, is also poisonous to your body, so it processes it out second. Ketones, on the other hand, are produced[1] by the body, so can stick around as needed. 1. Trust me, I know everything produced by the body is not good. It's just that, when comparing ketones to glucose and alcohol, I think ketones win hands down.
papsosouid 14y ago
Those low carb diets are also diets that reduce your ability to engage in strenuous activities, and cause muscle wasting. The idea is to be healthy, not to lose weight or treat epilepsy.
- Evgeny 14y ago
  and cause muscle wasting Low carb diets do not cause muscle wasting - at least if one continues to exercise. I.e: Very-low-carbohydrate diets and preservation of muscle mass http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1373635/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1373635/
  - papsosouid 14y ago
    >Low carb diets do not cause muscle wasting - at least if one continues to exercise. Which you can't do because your muscles have no glycogen stores.
    - Evgeny 14y ago
      My understanding is that when carbohydrates are in short supply, then gluconeogenesis kicks in and liver starts producing glucose from lactate, glycerol and amino acids. I.e. some information can be found here: Low-Carbohydrate Diet Burns More Excess Liver Fat Than Low-Calorie Diet, Clinical Study Finds http://www.sciencedaily.com/releases/2009/01/090120074631.htm http://www.sciencedaily.com/releases/2009/01/090120074631.ht... I personally did not follow a low carb diet for more than 12 weeks, but I kept my regular 3 times per week workouts and maintained my strength while losing about 8kg bodyweight from ~83 to ~75 kg. My workouts were fairly short (40 to 50 min), but quite intensive.
- commandar 14y ago
  >Those low carb diets are also diets that reduce your ability to engage in strenuous activities That's because low carb diets cause stored glycogen in muscles to be shed. That glycogen is used by the muscles for immediate energy during anaerobic exercise (e.g., weight lifting) when a sudden burst of energy is needed. It has less effect on aerobic exercise like running. You can still lift heavy things in a glycogen-depleted state; you will be come fatigued sooner, though. >and cause muscle wasting That's not really true. Extremely low carb diets were in use by body builders during the cutting phase of their routines for decades before they gained any sort of mainstream popularity, specifically because they they allow retention of muscle mass while shedding fat.

deleted 14y ago

[deleted]

duskwuff 14y ago

Ketone metabolism works, but it's treated as if it's some kind of fallback -- it's only used when no other source of energy has been available for a few days. While it does seem like it's helpful in some situations, the way it's treated leads me to suspect it's probably harmful in the long run for otherwise healthy individuals.

SoftwareMaven 14y ago
I look at it just the opposite. Alcohol, in too much quantity, is essentially poisonous to your body, so it processes it out first. Glucose, in too much quantity, is also poisonous to your body, so it processes it out second. Ketones, on the other hand, are produced[1] by the body, so can stick around as needed. 1. Trust me, I know everything produced by the body is not good. It's just that, when comparing ketones to glucose and alcohol, I think ketones win hands down.

papsosouid 14y ago

Those low carb diets are also diets that reduce your ability to engage in strenuous activities, and cause muscle wasting. The idea is to be healthy, not to lose weight or treat epilepsy.

Evgeny 14y ago
and cause muscle wasting Low carb diets do not cause muscle wasting - at least if one continues to exercise. I.e: Very-low-carbohydrate diets and preservation of muscle mass http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1373635/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1373635/
- papsosouid 14y ago
  >Low carb diets do not cause muscle wasting - at least if one continues to exercise. Which you can't do because your muscles have no glycogen stores.
  - Evgeny 14y ago
    My understanding is that when carbohydrates are in short supply, then gluconeogenesis kicks in and liver starts producing glucose from lactate, glycerol and amino acids. I.e. some information can be found here: Low-Carbohydrate Diet Burns More Excess Liver Fat Than Low-Calorie Diet, Clinical Study Finds http://www.sciencedaily.com/releases/2009/01/090120074631.htm http://www.sciencedaily.com/releases/2009/01/090120074631.ht... I personally did not follow a low carb diet for more than 12 weeks, but I kept my regular 3 times per week workouts and maintained my strength while losing about 8kg bodyweight from ~83 to ~75 kg. My workouts were fairly short (40 to 50 min), but quite intensive.
commandar 14y ago
>Those low carb diets are also diets that reduce your ability to engage in strenuous activities That's because low carb diets cause stored glycogen in muscles to be shed. That glycogen is used by the muscles for immediate energy during anaerobic exercise (e.g., weight lifting) when a sudden burst of energy is needed. It has less effect on aerobic exercise like running. You can still lift heavy things in a glycogen-depleted state; you will be come fatigued sooner, though. >and cause muscle wasting That's not really true. Extremely low carb diets were in use by body builders during the cutting phase of their routines for decades before they gained any sort of mainstream popularity, specifically because they they allow retention of muscle mass while shedding fat.