Ray Peat On Ketones Vs Glucose

rei

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caprylic acid reliably converts into ketones under all physiological conditions, a true superfuel for your body. MCT oil is a cheap substitute that still gives generally good results because much of it is caprylic acid :)
 

Yucca

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(first, sorry as english is not my 1st language)

I'm not really a peatarian, mainly a keto-dissident here (with intermittent fasting, and 2/3 weekly carb reloads also, as I train with weights on a regular basis).
I totally disagree with the idea that ketosis and fasting would be bad because of higher cortisol/stress.
It's only the case for NON ADAPTED Ketoers.
If you eat the usual daily carbs amount in Western countries, it needs at least 3-4 weeks to be fully keto adapted, even up to 6 months if you're not very fit to begin with. You do have hypoglycemia, low energy, stress, higher cortisol if you don't eat for hours.
When keto adapted, you don't ever feel hunger or thurst. I did already a 3 days dry fast without problems, no stress at all, no increased cortisol, glucose levels are steady and on the middle/low side (about 0,80mg/dl all day long, and never goes up over 1,1/1,2 even after a meal, then return quickly to base levels after. Mental clarity and energy levels are also much higher when in ketosis.

You won't find any real world studies about this, because it doesn't interest meds or pharma labs. ALL clinical studies with low carbs were done with men/women not keto adapted, so it's totally logical that it raised highly their cortisol...
When you find some studies with competitive athletes (read Jeff Volek's books and also Ben Greenfield), the results are about the same between high carbs diet and keto, WHEN they become keto adapted (not before : 10 days or 2 weeks low carbs is not enough). The difference is that there's way way less inflammation levels in keto athletes. But ketosis must be induced with diet only, NOT external supplementation.

So no OJ for me if I ever be hungry. Only black coffee, fat raw cheese or cashew, and my bloodtests have never been as good for all my life (only 0,5g/l triglycerides, 0,8g HDL and 0,9 LDL...with 70% daily fats ! Testosterone levels are also higher than before, but I take about 8000iu vit D + 25 mg zinc, + 10mg boron + 500mg ashwaganda each day...). Hematocrit is at 50% (at 54 years old) when I was at 42-46 most of my life...
Even C-reactive protein is so low in my blood that the lab was unable to measure it !! (Quite high a few years ago when I was carb loaded...)
 
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Nomane Euger

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I
 
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(first, sorry as english is not my 1st language)

I'm not really a peatarian, mainly a keto-dissident here (with intermittent fasting, and 2/3 weekly carb reloads also, as I train with weights on a regular basis).
I totally disagree with the idea that ketosis and fasting would be bad because of higher cortisol/stress.
It's only the case for NON ADAPTED Ketoers.
If you eat the usual daily carbs amount in Western countries, it needs at least 3-4 weeks to be fully keto adapted, even up to 6 months if you're not very fit to begin with. You do have hypoglycemia, low energy, stress, higher cortisol if you don't eat for hours.
When keto adapted, you don't ever feel hunger or thurst. I did already a 3 days dry fast without problems, no stress at all, no increased cortisol, glucose levels are steady and on the middle/low side (about 0,80mg/dl all day long, and never goes up over 1,1/1,2 even after a meal, then return quickly to base levels after. Mental clarity and energy levels are also much higher when in ketosis.

You won't find any real world studies about this, because it doesn't interest meds or pharma labs. ALL clinical studies with low carbs were done with men/women not keto adapted, so it's totally logical that it raised highly their cortisol...
When you find some studies with competitive athletes (read Jeff Volek's books and also Ben Greenfield), the results are about the same between high carbs diet and keto, WHEN they become keto adapted (not before : 10 days or 2 weeks low carbs is not enough). The difference is that there's way way less inflammation levels in keto athletes. But ketosis must be induced with diet only, NOT external supplementation.

So no OJ for me if I ever be hungry. Only black coffee, fat raw cheese or cashew, and my bloodtests have never been as good for all my life (only 0,5g/l triglycerides, 0,8g HDL and 0,9 LDL...with 70% daily fats ! Testosterone levels are also higher than before, but I take about 8000iu vit D + 25 mg zinc, + 10mg boron + 500mg ashwaganda each day...). Hematocrit is at 50% (at 54 years old) when I was at 42-46 most of my life...
Even C-reactive protein is so low in my blood that the lab was unable to measure it !! (Quite high a few years ago when I was carb loaded...)
when you restrict your carbohydrate intake, your body must make glucose form non-carbohydrate sources in a process called gluconeogenesis. cortisol is the primary metabolic regulator of gluconeogenesis, and because this process is wasteful, ketones are also produced to supply energy instead of glucose. ketones are produced when gluconeogenesis is converting amino acids into glucose, so cortisol is the primary metabolic regulator of ketogenesis (the creation of ketones). so, cortisol not being raised on a keto diet is physiologically impossible.
 

Yucca

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Converting amino acid into glucose doesn't necessarily generate increased cortisol.

Studies on rats (with a totally different metabolism) and fat people can't be generalized with keto adapted, fit people.
 
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Converting amino acid into glucose doesn't necessarily generate increased cortisol.

Studies on rats (with a totally different metabolism) and fat people can't be generalized with keto adapted, fit people.
As I said, converting amino acids into glucose (gluconeogenesis) is primarily regulated by cortisol, in humans (who mentioned rats?). Just a simple fact mate. Yes, "Converting amino acid into glucose doesn't necessarily generate increased cortisol.", no one has said that. It's the other way round. Ketones are only generated when your cortisol is raised enough to trigger this process of converting amino acids into glucose. If you'd like to understand the specifics, oxaloacetate is pulled out of the Krebs Cycle to be used as an intermediate in gluconeogenesis. When oxaloacetate is pulled out, Acetyl-CoA has nothing to react with to form Citrate, causing Acetyl-CoA levels to build up. Excess levels of Acetyl-CoA are then converted into ketones, those ketones enter the brain and muscles and are turned back into Acetyl-CoA.
 

Niteowel

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when you restrict your carbohydrate intake, your body must make glucose form non-carbohydrate sources in a process called gluconeogenesis. cortisol is the primary metabolic regulator of gluconeogenesis, and because this process is wasteful, ketones are also produced to supply energy instead of glucose. ketones are produced when gluconeogenesis is converting amino acids into glucose, so cortisol is the primary metabolic regulator of ketogenesis (the creation of ketones). so, cortisol not being raised on a keto diet is physiologically impossible.
Agree
 

Yucca

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Impossible if you’re not keto adapted.

When you’re not adapted, glucose levels is still high on mornings.
when you’re adapted, glucose is at 0,8 or below. And cortisol is also always low, because energy from fats is infinite, your tank is always full, even ripped people.
Its a totally different energy pathway with glucose metabolism.

This makes the difference. And it needs up to 6 months (or never for some people!!)
 

Bad Linhat

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Impossible if you’re not keto adapted.

When you’re not adapted, glucose levels is still high on mornings.
when you’re adapted, glucose is at 0,8 or below. And cortisol is also always low, because energy from fats is infinite, your tank is always full, even ripped people.
Its a totally different energy pathway with glucose metabolism.

This makes the difference. And it needs up to 6 months (or never for some people!!)
If ketosis is so difficult to achieve or impossible for some and it is so easy get out (only a small amount of carbs is sufficient) are sure that is a natural and safe mechanism in the long term ?
It’s clear that the body prefer glucose if available.

During the Paleolithic what are supposed to eat men to stay into ketosis ?
 

Yucca

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died animals. Mainly offals (not sure it’s the English word ?)
Liver, heart, game meat...
And some easy to find berries.

i can’t vouch ketosis is safe on the long term..
I personally try intermittent fasting, with a small daily carb refeed, ideally after weight training. As I was keto adapted to begin with, I’m back into ketosis after 14-15h of fasting. Then I wait 3-4h more and I eat all my carb intake (never more than 70-100g max) . My eating window is never more than 6-7h/day.

But it’s me, of course. It’s the result of 10-15 years of tries and fails.
One size never fits all.
 
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Bad Linhat

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died animals. Mainly offals (not sure it’s the English word ?)
Liver, heart, game meat...
And some easy to find berries.

i can’t vouch ketosis is safe on the long term..
I personally try intermittent fasting, with a small daily carb refeed, ideally after weight training. As I was keto adapted to begin with, I’m back into ketosis after 14-15h of fasting. Then I wait 3-4h more and I eat all my carb intake (never more than 70-100g max) . My eating window is never more than 6-7h/day.

But it’s me, of course. It’s the result of 10-15 years of tries and fails.
One size never fits all.

To have high fat intake paleo men had to kill many animals because in nature are usually quite lean.
Also i don't know how many berries they can find: berries ara not hot climate plants, and did paleo men avoid all other (tropical) fruits ?

At my eyes your diet is not ketogenic: 70g carbs are too much to remain into ketosis (some source recommend no more than 20g a day).

Obviously i don't want to criticize your routines if they work for you and are the result of 15 years of experience.
 

Yucca

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My diet was keto for the last years, but not anymore, as I want now to improve my thyroid levels.
Its a low carb diet, with a keto window of about 3-4h/day (blood mesured), at the end of my daily 18h day fast.

Once again, I don’t claim it’s for everyone, but it seems to work for me. The worst part of my existence was when I was high carb. Definitively not for me.
 

Aimer

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RP: Ya, and those short chain saturated fats happen to have sort of a hormone-like effect. They have an anti-histamine effect because they help to quiet the immune cells, keep them from producing too much histamine, and they protect cells from over reacting to toxic excitants like histamine, and they even immediately, when they are released as a free fatty acids and their first metabolic passes through the mitochondria, they release ketones. And these short fatty acids and ketones act like the GABA transmitters in the brain and other tissues to quiet and calm over-excited cells. The GABA system - people usually think of it as a nerve transmitter, but it's really active in all types of cells and it helps, for example, to slow excess cell division in tumors, and that's probably one of the reasons that the saturated fats are protective against tumors - that it's applying the brakes the way the GABA molecule would.
 

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