I've been looking a lot recently at the practical side of inducing dietary ketosis. But in the process, I learned about some fundamental misconceptions which are poorly addressed by the true believers. This is intended mainly as a springboard for debate, as opposed to any specific scientific thesis. Nevertheless, I think there are several issues here that deserve scientific scrutiny.
First of all, I would encourage you to watch the video below about the Ketonix ketone breathalyzer and how it came to be. Its inventor, Michell Lundell, explained that his goal was to create a device which exploited the rough correlation between exhaled acetone and beta hydroxybutyrate (BHB) in the blood. He did this, quite successfully, such that run-to-run variation is on the order of 1%, once the user is properly trained in the correct method of exhalation.
Unfortunately, if you look at his scatter plot, it's evident that the correlation itself (between BHB and exhaled acetone) is rather noisy. I would be surprised if the results were accurate to within less then 10%, on average. He circumvents this issue by asserting that what really matters is that when glucose is rising, acetoacetate (AA) is falling, and visa-versa. Therefore by measuring the change in detected ketones, we can at least see, quite accurately, the sign of the change in glucose. But we could probably just guess that, given the amount of carbs going into our mouths.
But this is where he presents a key point about ketosis which, as important as it is, I have never seen explained anywhere else: while AA is inversely correlated with glucose, BHB is essentially independent. On the one hand, this would tend to support the notion that merely taking a dose of coconut oil would cause glucose to drop, assuming that AA increases. OTOH, it also implies that we can raise total ketones (BHB+AA) as high as we like, yet still have plenty of glucose floating around wreaking havoc as usual.
In practice, this means that exogenous ketone precursors such as coconut oil, MCT oil, Pruvit, Brain Octane, etc. are only guaranteed to raise BHB, not to drop glucose to any "safe" level.
As far as Alzheimer's is concerned, these fats are nevertheless helpful, because when ketones reach a certain level, neurons supposedly switch over to them as fuel source, regardless of available glucose. However, the glucose is still there, glycating away everything in sight. Ultimately, that fuels neurodegeneration, albeit perhaps at a slower rate on account of neuronal energy availability.
On the cancer front, the increase in BHB can only be bad news, absent a bona fide ketogenic diet. I believe this because, in the presence of carbs, all we're doing is increasing total caloric intake, and thus morbidity. This might explain, for instance, why mice fed on a high coconut fat diet die sooner than their normally fed peers, even though in theory they should be in ketosis; the answer is that they're not in ketosis at all, because the glucose provided by the carb portion of their diet is overriding the increased availability of ketones. So all those folks force feeding themselves coconut oil in the hopes of staving off Alzheimer's are probably shortening their lifespans in the interest of sanity. That would be a compelling tradeoff, but we have can have our cake and eat it too... so long as we don't eat any cake.
The only practical answer to both chronic diseases would seem to be an actual ketogenic diet. This is something like 80% of calories from fat, 15% from protein, and 5% from carbs. On the plus side, I'm not aware of any evidence that restricting calories below ad libidum intake would provide any further benefit. (I suspect it would, but then, Jean Calment lived to 122 on a ketogenic diet, while smoking and drinking to boot, with no record of any effort to maintain CR.) In other words, eat whatever you want, so long as it's fat.
Which brings me to the following damned lie: various keto enthusiasts seem to espouse meal planning from a "reasonable approximation" standpoint. So for instance, let's say that we can eat 2500 calories per day. 5% of this would be 125 calories, or about 31 g of carbs. Some 100 g chocolate bars fit within that range. Therefore, we could have one chocolate bar per day, provided that the rest of the diet consisted of fat and protein.
But in practice, we can't afford the chocolate bar at all. The reason is that, for those of us without superhuman willpower, we need at least some nuts, seeds, vegetables, mushrooms, yoghurt, avocados, or cottage cheese. None of those foods are free of carbs, and moreover seeds are probably the worst offenders considering their bias toward omega-6. Even avocados are 8% carbs. Add up all these "trace" sources, and you have your 5%!
Keto practitioners also love to rattle on about how delicious the diet can be. It can't. It isn't. It's disgusting. People who say this are confusing low carb diets with ketogenic diets. I've been doing another keto spin myself for the last 2 months. As an example, for breakfast, I had one part each of avocado and cottage cheese, submerged in 2 parts extra virgin olive oil. It tasted horrible, and though it certainly filled me up, did not satisfy me in any way even close to what that would mean to, say, a vegetarian used to eating sweet potatoes. I don't care if you think you're a carnivore because you can eat an extra large meat lover's pizza in minutes. If you've never tried a ketogenic diet, you have no idea what you're in for. And if you're vegan, you're probably going to need exogenous digestive enzymes for a while until your body can catch up with production thereof.
The other great myth is what it does for your brain. It doesn't enhance peak performance. Nor does it chelate toxic ions out of the brain. Only phytochemicals (and some pharmaceutical agents) can do that... from good old sugar sources like beets, brocolli, ginger, and kale. My peak brain performance was unmistakably higher on an ultra-high-sugar juice diet, than keto. I've spent enough agonizing days on both diets to be sure, at this point. Part of the reason may also be that glucose actually provides for higher performance over brief durations, than does fat, assuming that PDH complex and friends are in good shape; it just burns dirtier. What the ketogenic diet does do for the brain is to retard the rate of oxidation and neurodegeneration, allowing endogenous cleanup processes and very slow neurogenesis to improve one's cognitive health over several months. It also provides for moderately more protein intake than one would have on a typical vegan diet, which is presumably anabolic in the brain to some extent.
I must emphasize, having poured over supercentenarian diet anecdotes for quite some time, that we have several reports of such individuals eating significant quantities of vegetables, sweet potatoes, and even normal potatoes. The only truly ketogenic supercentenarian, if there ever were one, was Jean Calment. She beat the supercentenarian carb eaters by several years, but then there are several of the latter, so the statistics are at least questionable. Which brings me to another keto myth, which is that sugar is so evil that it overrides the benefits of even the more potent phytochemicals, and even in the context of an active lifestyle.
Based on the data, I would have to say that even if this is true, that it's true by a small margin which may not be worth the decades of olive oil misery. More importantly, I think we can all agree that sustainability is more important than optimality, so those who can't stand to immitate Calment would probably be better off following a carbivorous supercentenarian diet, free of dairy other than butter and eggs. For that matter, juice fanatic Charlotte Gerson is in her mid 90s and shows no signs of dementia, so it's clear that keto enthusiasts need to temper their antiglucose rhetoric with the knowledge that the right phytochemicals can significantly override glycation.
Which brings me to yet another myth: total carbs. Is it really total carbs that matters, or the total area under the 24-hour glucose curve? On the one hand, if we ultimately burn whatever carbs we eat, then PDH is getting hammered the same amount, regardless of whether it occurs in a 100 m sprint, or all day long while playing cards. But OTOH, the glucose in the former case isn't sitting around for very long, which strictly limits its ability to destroy things before being converted into CO2 and water. It's informative that the vegetarian supercentenarians tend to live in hilly areas lacking modern conveniences.
On the plus side on keto, I can promise you that a keto diet will give you amazing endurance. You won't have more peak energy than normal -- less, actually -- but your ability to keep moving will be unmatched relative to any other diet. You'll probably also be a bit dumber than you would on a vegan juice cleanse. But then, it's probably better to be a bit dumber with twice as much time to get things done before you feel like taking a nap.
Last but not least is the ethics question. Keto practitioners kill animals, and often those with higher intelligence who are found higher on the food chain. Their reward for this killing spree is the prospect of a longer and richer life with more energy to pursue their dreams. To their credit, those animals are spared the horrendous travails of senescence which have plagued humans for the past century. But obviously there are negatives to the killing, and probably to a larger extent, substandard animal husbandry. Vegans, by definition, don't do this at all. Does this make keto folks evil and vegans good? I don't think it's that simple, speaking as a person who is very concerned with animal welfare. Merely by just living on this planet, we're consuming resources and creating pollution because it's impossible to live without making some such negative impact. If I can kill an animal and be twice as productive in the time I have, then perhaps I can do some good deeds that would have been impossible otherwise. I could also choose to focus on less sentient sources of meat such as mussels and eggs, at the peril of domoic acid poisoning or excessive iron consumption in the former case. Or if I felt the need to eat, say, a steak, I could buy it at a bargain basement discount, so low that if everyone did the same, the beef industry would go bankrupt. There are no clean answers here; it's all a question of tradeoffs like anything else in life, but let's not make the mistake of thinking that the issue is black-and-white, or tell people "don't judge me" because we're afraid to own up to the destructive side effects of our behavior, however justified it may be. Go ahead, judge me. Just provide me with a better recipe for living. Ultimately, the solution lies in vitro meat: we need to get the animals out of animal foods.
Edited by resveratrol_guy, 22 January 2017 - 09:58 PM.