Further to my last post, regarding one’s genetic predisposition to efficiently metabolizing carbs, I realize it seems kind of bleak and unfair. I do think there is hope though. If someone wants to start trying to reintroduce carbs, I think it helps to use some trial and error. You might be fine eating one kind of carb and not another. For example, I can eat a potato without any noticeable negative side effects, but bread is a no go. I won’t be in ketosis after the potato of course, which is not optimal, but I won’t necessarily gain weight or feel awful afterward. I seem to be fine with berries, but I doubt the same would be true of a lot of other fruits. If you do want to experiment, I would suggest looking at what carbs raise your blood sugar the most and go from there.
Metabolic Flexibility - Get Real
And keep in mind that the Drs. Eades in Protein Power (a new edition coming out soon) briefly mention their plan’s goal for their patients is to inhabit the ‘keto cusp’. That being able to move in and out of various degrees of ketosis is a more robust/agile/flexible state for longterm health and preferable over some external ideal of 24/7 deep ketosis.
When I first read that a few years back in my early months of keto, it made intuitive sense to me, sort of like how certain martial arts and yoga techniques rely on an equanimous embodiment that can spring into action one moment, and return to embodied stillness the next. Without that internal energetic range of response, one misses the art part of the science. For me it connects also to LCHF/keto, as a co-creative experience as much as a self-discipline - with quite a wide range of capacity when IF is comfortably part of the week, and fatty coffees gird ones brainz, etc. 
Did they provide any evidence that being in a deep state of ketosis in any way prevents ones from moving in and out of ketosis easily. I’ve got ketones between 1-3.5 all the time and can leave ketosis easily and get back in the next day. By what mechanism is regular deep ketosis supposed to hamper this flexibility?
Their work is based on thousands of clinical patients - and heavily referenced - highly recommend checking it out if you’ve not read Protein Power.
Healthy physiology for the long term is so much about adaptability amidst constant change, ie, antifragility rather than mere robustness (though healing enough to recover robustness is a necessary step). I’ve also quite enjoyed the research of Romanian engineer Christian Vlad - his book Stress and Adaptation in Physiology: Perturbation - Between Poison and Medication goes into great detail on mechanisms from a LCHF/keto perspective.
I’m sure it is but I’m asking about a specific claim. Even the best scientists can make poorly sourced claims. In fact I don’t even know if they’ve made this claim at all. I’ve read a lot of research about ketogenesis and have never come across it. Could you please provide a quote or reference stating that long-term deep ketogenesis inhibits the flexibility “to move in and out of various degrees of ketosis”.
I believe it’s been quoted before somewhere here on the forum before - no not going to search it and type it out for you as I’m up to other things, but I did generally summarize it already and point you in the right direction. And of course, please don’t just take my word for it - get yourself a copy of PP and familiarize yourself with the work of the Drs. Eades who are foundational people in our LCHF/keto world. 
What she quoted was
It did not imply that there was any problem with being in 24/7 deep ketosis. It implied that for many (probably most) people in today’s world, it is not actually necessary.
More people are able to eat lowcarb or moderately low carb than keto. Keto might be better in some respects, but nobody benefits from a diet they’re not on.
Ow. This is brilliant PJ. I need a quiet space alone with this thought (that would be great on a t-shirt that could be worn to any health and nutrition meetup or street march)
I have no issue with this and agree entirely.
However I reread @SlowBurnMary’s posts and still see her as saying that 24/7 ketosis leaves one less able to move in and out of various states of ketosis and in a less robust, agile an flexible state for long term health".
If all she was saying was that not everyone can be happy with a ketogenic diet and many are able to do well enough on a low carb “keto cusp” diet which is clearly better than the SAD, then I have no argument with that position.
Everyone can call it what they want, but the bottom line default State is that of low liver glycogen levels, allowing people to primarily be in Lipolysis. When occasional carbs are eaten and Lipolysis temporarily halts, any excess first goes to muscle glycogen, then afterwards to the liver. As long as carbs are not consumed chronically, the body is able to easily change back to Lipolysis fairly quickly, let alone fill liver glycogen and begin any type of fat storage.
I see what you mean.
Well I’ve been online in the ‘low-carb and keto’ worlds for many years. A few years while I lost a lot of weight, then I got sick (heart issue) and for nearly a decade was nearly then fully bedridden so I spent a lot of time on my computer… reading forums and more. Been about 18mo since I was recovered enough from heart surgery and managing ok with the diuretics to re-began keto. And in that time of onlooking… well there’s just a ridiculous number, I’d say even just huge %, of people who, when eating keto diligently, try to eat high carb for a day and it takes them 1-2 weeks to get their body back into using fat like it should and them not craving carbs so bad it was crazy.
I was this way too for a long time. I am not anymore.
This makes me think a couple of things.
First: I think maybe it takes a certain amount of healing, for people with really forked metabolisms, before they can get to what we are calling metabolic flexibility. For all I know it means some healing on the liver or something. The real world sitch seems to be that a ton of people eating ketogenically cannot be ‘flexible.’
For them, keto really is like a bleepin’ light switch, you “throw yourself out” and when you finally get back “in” it’s a sea change in energy, you know you’ve “suddenly shifted fully into ketosis.” If they throw themselves out of that state, it takes the entire induction period – ranging from 5 to 21 days depending on the person – to get back to it again. It sucks, it’s miserable, and it tends to make them either stay religiously to the plan – er, that’s the lower number, ha – or it makes them eat one meal off plan and then, having suffered before, they say screw it, and they just stay high carb, until finally misery or health panic drives them back to suffer through getting into ketosis again.
Obviously not everyone is in that situation, but a ton of people are. I’m guessing the reason it’s so many people is because most people do not pursue lowcarb unless they have serious metabolic syndrome. So by then, the self-selected group of participants tend strongly toward having serious fatty liver and other issues.
Now, I haven’t heard of any evidence that eating on the high side of lowcarb – let’s say ranging from keto to about 70 carbs depending on the day – would somehow entrain the body to go back and forth more fluently, between ketone generation versus exogenously-spawned glucose, than simply plowing through ‘deep keto consistently’ in the attempt to heal the body as quickly as possible. It might not.
But then we get to:
Secondly, I think the Eades’s are probably attempting to address a larger market than people already eating keto or lowcarb. Pretty much everyone in our society would vastly benefit from dropping from their 250-400 carbs a day or more to 75. I mean if we could encourage people to do that, it would be a drastic, massive improvement in their health. Maybe not as fast or intense as keto, granted. Maybe for some people already so damaged metabolically it wouldn’t be enough, or, at least some wouldn’t have enough lifespan left to make it enough. But it definitely would be a way of eating pretty healthy, certainly healthiER, than the standard american diet (SAD) currently.
I did not get to the point where I could go fluently in and out of making ketones (on the blood monitor) until last year [edit to add: I didn’t measure until last year, so I am using ‘perceived keto symptoms and energy’ as the measure prior], and this corresponded with my shifting to a diet more commonly lowcarb than keto, and having ‘carb-up’ days (usually about 60 but as high as 120 rarely) every 7-10 days.
However, that doesn’t mean this is what ‘fixed’ me. It might simply be that enough time had passed with me taking good supplements (liposomal C and liposomal silymarin for the liver), eating well (mostly) (I love pepperoni dammit), and losing more weight, that finally got me to the point where I can. Since I can’t project an alternate reality for myself I have no way of measuring the why or how.
Humans are made to do this fluently. It’s not that it’s some magic that we do, it’s some dysfunction that some people don’t.
edit: sorry I see I kinda repeated what you already said. I can’t sleep (fasting makes me wired, I finally got up after being awake all night) and my brain is weary…
I enjoy reading your posts. I like the way you think and consider the angles. I agree with what you’ve said above and you make a good point that the trauma involved in reentering ketosis might be far greater for the metabolically damaged which would represent a high proportion of people entertaining the ketogenic diet. But as you’ve also said, it’s unclear if regular carb ups would help those people.
I know for myself and my husband going in and out of ketosis is a matter of a day; two at the most (but then only after a week + of carbs). And I only have carbs three or four time a year. This rarity doesn’t seem to be hindering the flexibility. But I’m metabolically in good health. My blood glucose is generally in the sixties unfasted.
That’s not what the Drs Eades are saying - their clinical aims for fully adapted clients are to keep the body on the edge/cusp of ketosis as a way of supporting max metabolic agility across the 24 hour cycle - and preventing downreg. It’s a well developed clinical protocol with stunning results in very unhealthy people - they’re awesome.
That would be refreshing, Although it’s a concept that’s been around for decades, at least in the Bodybuilding Lifestyle. Carb intake for metabolic purposes gets, IMO, almost irrational, but really more like religious disputation. It’s probably the most annoying aspect of “Nutty Keto Dogma”. Especially to someone who’s experienced.metabolic downregulation, sometimes called a.Starvation Response.
Restarting this topic with an interesting overview.
I can’t imagine how I missed this thread the first time it came up. Here’s my screed, if anyone feels like reading it.
Metabolic flexibility means the ability to metabolise both glucose (glycolysis) and fats (fatty-acid metabolism). The problem with excessive serum glucose (carbohydrate being nothing but glucose molecules arranged in various ways) lies in the the damage caused by hyperglycaemia and by the resultant hyperinsulinaemia. Eating a diet too high in carbohydrate for too long (exactly what constitutes “too high” and “too long” being highly variable from individual to individual) causes damage to mitochondria from advanced glycation end-products (AGE’s) and reactive oxygen species (ROE’s). This results in a lack of metabolic flexibility, caused by the mitochondrial damage and by the deactivation of certain metabolic pathways from lack of use. What we call “fat-adaptation” is the reactivation of these pathways and the healing of the mitochondria. Cells never lose their ability to metabolise glucose, no matter how long we remain in ketosis.
I’m sensing a lack of clarity in the thinking behind this statement. Try putting it this way:
I’m considering getting sober in late February after my next set of blood work but I’m very nervous about losing the ability to drink certain liquors. I don’t track but I do drink these liquors almost weekly in small doses and hope to retain the ability to process them.
Looking over this re-written paragraph, no one would argue that alcohol is necessary for life. Millions of people have lived alcohol-free for decades with no apparent difficulty. Likewise, carbohydrate is not necessary for life, either.
What does happen, however, is that people who used to be alcoholics, say, lose their tolerance for alcohol after a while in sobriety, and if they start drinking again, they need to rebuild their tolerance, the way they did when they first started drinking. (The medical term for this is “habituation.”) I believe that a similar phenomenon obtains with carbohydrate.
This habituation to carbohydrate is complicated by the fact that plant foods contain not only carbohydrate but phytochemicals that cause various effects. I expect that there is probably an habituation process with these phytochemicals, as well. As long as we retain our habituation, we don’t feel their effects, but once we clear our bodies long enough, reintroducing them causes problems. We don’t remember having to become habituated to carbohydrate and phytochemicals, because most of us have forgotten being weaned from our mothers’ milk.
Another quotation begging to be rewritten: “We SHOULD be able to eat arsenic without a horrible punishment, regardless of whether arsenic is ‘healthy’ for us on paper.”
This is true, but does the absence of the toxin pose a problem? And is every micronutrient necessary under all circumstances?
Take vitamin C, for example. It is prized for its antioxidative qualities, but perhaps it is necessary only on a high-carb diet, especially since elevated serum insulin activates genes that shut of our bodies’ endogenous defences against oxidation. On the other hand, the β-hydroxybutyrate generated by eating ketogenically shuts off these genes again, thereby reactivating our endogenous anti-oxidants. It appears highly likely, especially given the results of the experiment on Stefansson and Andersen (who disappointed the researchers by failing to develop scurvy on their all-meat diet), that we need far less, and possibly even no, vitamin C on a ketogenic diet. The researchers should not have been surprised; the anti-scorbutic effect of fresh meat has been well-known for centuries. Scurvy developed on Royal Navy ships only after the fresh foodstuffs were consumed, and the men’s diet switched to ship’s biscuit and salt beef. Limes and lemons are much easier to store in a cramped hold than livestock for fresh meat.
A lot of this could quite easily be the result of the effect of fructose (which is one-half of a sucrose molecule, the other half being glucose) on the brain. Fructose and ethanol behave very similarly in the body and are handled in the liver and brain the same way. The main difference is that fructose lacks the short-term toxicity of ethanol. Many people assume that if ethanol gives them a hangover the next day, it means they should either avoid it or be very careful not to overconsume (whatever that means in their individual case). Why not draw the same conclusion about sucrose?
If you’ve reached this point, you have my admiration for your patience, and my thanks for reading! 
Religion takes over…
Hangovers are caused by dehydration. They are easily avoided by consuming water while drinking alcohol.
So we’re comparing arsenic to rice or a potato? That’s an apples to bowling balls comparison. You can’t compare something known to be toxic to us, to something the majority of the population eats everyday without issue.
If an HCLF eater had my Bacon Cheeseburger Caserole which is world famous BTW, I’m willing to bet they’d do some toilet time over it. Is it because it’s toxic like arsenic? Or simply because their body isn’t used to fat in those levels? Would the arsenic comparison work then, or would it just be thought that the way they eat did that do them and when they started eating more fat stuff like that wouldn’t happen anymore?
I can eat bread and pasta and rice for days on end, flip back to keto for days, or back and forth as I see the need, no headaches, no moving my desk into the bathroom, no glycogen depletion headaches or keto flu… nothing! Our bodies shouldn’t make us sick simply because we eat something that’s not off a specific list minus it truly being bad for us, meaning actually bad, not meaning not part of your current WOE.