Changing Carbs, is it good?

(Bob M) #21

I wouldn’t get too concerned with any measurements, as do we really know what’s happening?

Here’s a day I took with ketones (forget which meter; I have several types) and with a FreeStyle Libre 14 day US sensor:


Am I “out of ketosis” in the morning when I got a 0.1? What about at 2:05 pm, when I got a 0.3?

Now, you might think: he must have eaten carbs the day before, and that’s why his ketones are so low. And you’d be wrong. This is what has happened to me over time:

And if you ever start testing the error the meters, it’s high. Really high. I have a picture (need to find that) where I compared two Keto Mojos and one Precision Xtra for ketones, and got 0.8, 0.4, and 0.2. What’s the real value?

As gross measures of what’s going on, they are OK. As exact measures, they aren’t.

And for someone like me, I’ve been doing this so long that they don’t tell me much, and I can’t understand a lot of what they do tell me. For instance, breath and blood ketones are often completely divergent: BHB can be 1.0, and the breath will be all over the map for that value of BHB. What does that mean, and why? It’s tough to say without more data analysis than I can do.

(Bob M) #22

You can see the divergence above: breath ketones are 16 and 42, so at least double, while BHB = 0.2. Why? No idea.

Since I’m using only my ketonix now (taken usually only in the morning), breath ketones for me seem to indicate how much fat I ate yesterday. If I eat more fat, the value seems to go up. But I haven’t done any exact testing, only know that seems to be the pattern.

Further, if breath ketones go up because of the fat I ate yesterday, what does that mean? I’m not sure it’s meaningful.

(Bob M) #23

I think one thing ketones represent isn’t usage but extra fat circulating in your blood. If you don’t believe me, fast for a few days, take your ketones, then eat a super high fat meal and take your ketones after then, maybe every hour or so. Will those ketones be used? Maybe; maybe not.

(Ellenor Bjornsdottir) #24

Hold that thought.

You know about this thing called gluconeogenesis? One can be still alive, not eating any carbohydrates, and not producing any ketones. It’s rare, and would cause accelerated muscle catabolism, but it’s definitely possible.

It’s also possible that in addition to GNG, a lot of these people’s energy needs are being met by fat directly.

Someone needs to conference Dave Feldman into this thing.

(A fool and his bacon are soon parted) #25

I wonder if it could merely be excess energy being excreted.

(A fool and his bacon are soon parted) #26

Gluconeogenesis is fairly tightly regulated between glucagon and insulin, though things can sometimes go wrong. Here is Roger Unger’s take on the matter:

(Michael - When reality fails to meet expectations, the problem is not reality.) #27

My understanding of gluconeogenesis is that it’s there primarily to make sure the brain gets the minimum glucose it requires regardless of dietary intake of nutrients. It does not supply the rest of the body with glucose. At best, the brain can only utilize ketones for up to about 2/3 of it’s energy requirements. So gluconeogenesis synthesizes sufficient glucose to meet the remaining demand from the brain. I don’t think we can survive on gluconeogenesis alone in the absence of ketones, specifically β-hydroxybutyrate, when consuming very low carbs simply because gluconeogenesis can only synthesize a relatively small amount of glucose daily.

Leptin in Initiation and Maintainance of Ketosis


There’s this correlation between rice consumption and high population sizes. I still believe that Asian populations would decrease drastically if rice is removed from their diet.



(Michael - When reality fails to meet expectations, the problem is not reality.) #29

@anon81060937 And this has what to do with gluconeogenesis?


According to the research. It seems sperm need to be bundled with glucose from gluconeogenesis so they can then penetrate the hard coating of the egg.

(Michael - When reality fails to meet expectations, the problem is not reality.) #31

Got a link for that? I would be interested to know just how a sperm cell, or the hard coating of the ovum, differentiates a glucose molecule derived from gluconeogenesis from a glucose molecule derived from a jar of strawberry jam.

(Bob M) #32

I believe it does mean that.

But it just shows how complex things are. Maybe those values indicate Ted Naiman is correct – I should be eating less fat. :wink:

(Bob M) #33

Just based on the thousands of tests I’ve taken on myself, I think this idea is justified. If my blood glucose is higher, my ketones are lower; and vice versa.

This is the general rule, though I’m sure there are times of discordance. For instance, exercise causes my blood sugar to go up, but typically does not affect BHB that much. (Though one wonders WHY the body does this: WHY does glucose go up? I think it’s glycogen replacement, but I’ve been known to be wrong in the past.)

There’s definitely a yin and yang between blood glucose and ketones, for those of us who are fat adapted.

And I think it’s hard or possibly impossible to “drive” gluconeogenesis. For instance, the idea that eating a lot of protein causes GNG and higher blood sugar does not appear anywhere in my data, and I even bought a year’s supply of CGMs to prove that it did. I ended up proving it did NOT. Or it doesn’t for me.


You misunderstood what I said.

(Michael - When reality fails to meet expectations, the problem is not reality.) #35

I quoted exactly what you said and ask for a link to support it so I can check it out.

Maybe you misunderstood what I said originally? I said gluconeogenesis evolved primarily to ensure the brain did not die of glucose starvation when intake of carbs was too low to provide the minimum glucose required. I said it did not evolve to provide the body generally with sufficient glucose to operate. That does not mean that other cells, organs that require some glucose to do whatever they do from utilizing some of the small amount of glucose synthesized by gluconeogenesis. Just that the brain has priority and will take it first. Whatever is left after the brain takes what it needs can certainly be used otherwise, for example by a sperm cell. But if it really requires a glucose molecule to penetrate an ovum’s shell, I’m sure the sperm cell doesn’t care where it came from.

(Ellenor Bjornsdottir) #36

Fructose, if I’m not mistaken.

(A fool and his bacon are soon parted) #37

Well, as a guess, if you are in need of explosive muscle performance, you are going to want some quick-burning glucose handy, right? But you are still going to want ketones to keep your heart and brain going, too, so I wouldn’t expect a drop in ketones under those circumstances. I wonder if cortisol doesn’t do something to the liver or pancreas to keep insulin from inhibiting ketogenesis.

When serum glucose rises because it’s in the diet, that is a completely different situation. In that case, we want to be storing fat, not burning it or turning it into ketones (i.e., partially burning it).

(A fool and his bacon are soon parted) #38

I wonder if this is actually true. And I’m only raising the question because Ben Bikman, who knows Cahill’s work, questions the notion—which I understand came from Cahill—that the brain needs 130 g of glucose a day. In fact, Bikman questions whether the brain needs any glucose at all.

(Michael - When reality fails to meet expectations, the problem is not reality.) #39

@PaulL That would certainly be an interesting matter! I also wondered why if the brain could function getting 2/3 of it’s energy from β-hydroxybutyrate it couldn’t function on it at 100%.

Watch the video I linked above of Dr Ali. Maybe he’s just repeating Cahill. Still, I have a lot of respect for Ali and it would take some convincing to swing me over, even though I’m inclined to ‘wish it were so’. Aside from the brain what else would require glucose sufficiently to evolve gluconeogenesis? In another discussion someone claimed that gluconeogenesis was around long before humans and we inherited it for whatever reasons. No documentation offered.

Leptin in Initiation and Maintainance of Ketosis
(Butter Withaspoon) #40

Red blood cells?

When the glycerol backbone of the triglyceride is converted to glucose, this is also gluconeogenesis. It makes sense that the body would utilise this fuel source when mainly burning fat.

No sources, just enjoying thinking about these things