How much is ketosis vs just "low carb"

(mole person) #21

Glycogen.

Actually, very little is in healthy adults. As @carolT has shown it’s a tiny fraction of a single gram, on average.

(You've tried everything else; why not try bacon?) #22

I’m afraid I’m not following. The usual carbohydrate intake on the SAD certainly does not allow for much glycogen depletion, if any; and I doubt that even intake around 100-125 g/day will, either, given that the body prefers to keep no more that 4-5 grams of glucose circulating in the bloodstream at any given time. Not counting periods of vigorous exercise or fasting, which are special cases.

(You've tried everything else; why not try bacon?) #23

There is a limit to the amount of glycogen that muscles can contain—I forget the figure, but it’s what leads to metabolic insulin resistance of the muscle (the reason is that glycogen in muscle is trapped and cannot be shared, only burned). The liver, on the other hand, can enlarge to accommodate quite a quantity of glycogen, at least according to the sources I’ve read. I suppose there is a limit, but Dr. Lustig talks of patients whose “liver is down to their knees,” which is an obvious exaggeration, but which also makes the point. As I understand it, it is fat stored in the liver, not glycogen, which leads to hepatic insulin resistance, since there is a limit to how much fat the liver can store, but hepatic glycogen can always be released as serum glucose.

ETA: The irreducible nitrogen loss from the deamination of protein (amino acids, in other words) is 0.6 grams per kilogram of lean tissue a day. This is why the recommended minimum protein intake is set at 0.8 g/kg (to give a bit of a cushion).

#24

A quote from Body by Science, no reference cited but I’m sure it’s easily verifiable:

The average male human stores roughly 70 grams of glycogen in his liver and 210 to 220 grams in his skeletal muscles. (Females store about 20 percent less.)

That number does not include glycogen turnover from intense glycolitic exercise. The glycogen is used, then replenished from the bloodstream. It also doesn’t account for the difference between a sedentary post-menopausal woman and an active man (or woman!) with a large LBM. In the liver, glycogen storage is further restricted in cases of fatty liver.

The reason glycogen cannot be shared back into circulation is because muscle tissue does not contain the enzyme(?) glucose 6-phosphatase . Glycogen is a one way street into, but not out of, muscle regardless of insulin resistance.

In addition, glucose is forced into both muscle and adipocytes during high insulin conditions after a meal or in someone with chronically elevated insulin. This is the function of GLUT4 transporters. (see bodybuilding and insulin injection for a horror story… and they want the IGF) Where the glucose goes preferentially depends on a bunch of factors influencing the number of GLUT4 transporters available at the bloodstream side of the cell membrane and probably other things I haven’t considered yet.

Interesting twist I just saw [which makes sense because exercise causes a low insulin condition for maximum glucose availability. ] …

In contrast, the stimulation of glucose transport induced by exercise or hypoxia is independent of this enzymatic activity. https://www.sciencedirect.com/science/article/pii/S1084952196900312

Muscle glycogen is also replenished via insulin independent transporters called GLUT1 on what I take is a trickle basis.

#25

I’d like to revisit this question in a context other than ‘if a person needs high ketone levels for ____’.

I think a lot of us would say that elevated LDL cholesterol, particularly in a lean mass hyper responder, is not a bad thing but is a system of energy transport for fat. (see here). Also, peripheral insulin resistance (PIR) is a known phenomenon in long term ketoers, the theory being that glucose is stored in the blood in abundance because we might need it in a hurry and can’t make it as quickly as we’d like. An extreme case would be someone like Dr. Shawn Baker, who has elevated fasting glucose and A1C, according to current medical guidelines. (see here)

So… why is storing some extra ketones in the blood considered a bad thing (or at least a trivial by-product) in some circles of the keto world because it implies energy overload? To me, it looks like a more easily available form of energy for when we need it in a hurry. And, given the hypothetical choice between levels of 6 mmol G + 0.5 mmol K or levels of 5 mmol G and 1.5 K, I would opt for the latter myself. Boosting ketone levels before exercise by taking MCT or exogenous ketones is a strategy high level athletes use for extra available energy.

(Ken) #26

It’s because Lipolysis then occurs intermittently, as glucagon stops when you eat carbs. It resumes once the insulin spike is over, about two hours for simple carbs. If say, you eat 150g of carbs one day at one time, it’s still only 600 calories of energy, so once they are processed the body will turn back to Lipolysis for the balance.

Same thing with 20g of carbs, but the duration of time to return to Lipolysis is shorter.

(PJ) #27

Question: (based on @ctviggen post) doesn’t lower ketones in the blood merely mean that whatever your body is using, vs. what your body is making, is different? What I mean to say is: the change could be:

1 - that your body is making fewer ketones (perhaps relying more on glycogen/glucose)

2 - that your body is using more ketones (such as getting more exercise than you normally do)

3 - both of the above

Assuming you were not eating much in the way of carbs, would this not mostly, probably, imply that you are using more of them and so your body might shortly be making more of them to compensate for your increased expectation of activity and/or expectation of low-carbs?

In other words, who is to say that ketones in the blood being low might not be a good thing sometimes, bad thing sometimes, or a doesn’t-mean-good-or-bad-thing sometimes, and in short, outside a whole context of a longer period of careful tracking, just doesn’t mean much of anything good or bad?

PJ

#28

Glad to hear that. Last night I was at the sky box for an Astros beatdown of the Oakland A’s and said what the heck and ate about 150 grams of carbs. I have been doing super well and we had Shake Shack burgers etc/

Back on the wagon today exercising and not eating much at all. SO I am hoping all goes back to normal!

(You've tried everything else; why not try bacon?) #29

And by what logic is that desirable? I believe that is the source of my lack of understanding. I went to a great deal of trouble to get my muscles to re-engage with fatty-acid metabolism; it doesn’t seem effective to keep interrupting that process by re-introducing glucose to the system.

(BTW, “lipolysis” merely refers to the disassembly of triglycerides to get the component fatty acids through cell walls. From the way you are using the term, I suspect you are really referring to what is called “fatty-acid metabolism.” I agree that we should really be using “lipolysis” for that process, but the people who coin these terms don’t listen to me . . . [heavy sigh].)

(Ken) #30

It is totally fine, meaning not detrimental, during Maintenance. It also can be argued it prevents metabolic issues when done occasionally, subject to the individual.

It’s really my point that the perpetual <20g carb consumption level of Keto Dogma pushed by some is not only unnecessary, but silly. You can still lose fat with a higher carb level, but at a slower pace. I certainly do advocate a very low, or no carb consumption level during adaptation.