Wow! Such an informative article! A lot to take in! Loving that you mentioned the KETO//OS! I’ve actually lost 10 lbs in 3 weeks! Kinda cool. I haven’t heard of the other products but I’m excited the check them out! Also, the breath tool is new to me. Thank you! If anyone wants to checkout my testimonial with epilepsy, weight loss on the KETO//OS you can read it here: http://bit.ly/keto-os
There’s not enough of it to matter in coconut oil, it tastes bad, and it often results in stomach/gastric upset, but it does get converted quickly into ketones. If your MCT oil brand of choice makes your throat burn or has a weird flavor, one reason may be that the distillation did not remove enough of the C6. There are other reasons this can happen too, discussed below.
More good news: Snacks are totally allowed (and I'm not just talking about carrot sticks). There are plenty of packaged options out there designed for keto fans. FATBAR is one of them. These snack bars have 200 calories, 16 grams of fat, and four grams of net carbs. They're also plant-based and are made with almond or cashew butter, cocoa butter, coconut, pea protein, sunflower seeds, and chia seeds.
Before I highly suggest that you don’t purge your bread products, I’m going to play devil’s cautious-and-hardly-audible advocate and say, yes, drastically cutting carb and sugar intake can have health benefits: it can increase levels of good cholesterol, reduce blood sugar, and all that stuff. But you can accomplish these same goals by, for example, replacing Wonder bread with a healthier carb. There's no need to side-eye the croutons your server forgot to omit like they’re a physical manifestation of the Seven Deadly Sins.
If you are already in ketosis and accustomed to high-fat, low-carb diets, you can take one heaping scoop in about eight ounces of water fifteen minutes prior to working out. It stays in your system and will provide your body with elevated ketone levels for about three hours. When taken as a pre-workout, KetoCaNa has also been shown to decrease the amount of oxygen consumed at a given power output.
Because the ketogenic diet alters the body's metabolism, it is a first-line therapy in children with certain congenital metabolic diseases such as pyruvate dehydrogenase (E1) deficiency and glucose transporter 1 deficiency syndrome,[35] which prevent the body from using carbohydrates as fuel, leading to a dependency on ketone bodies. The ketogenic diet is beneficial in treating the seizures and some other symptoms in these diseases and is an absolute indication.[36] However, it is absolutely contraindicated in the treatment of other diseases such as pyruvate carboxylase deficiency, porphyria, and other rare genetic disorders of fat metabolism.[9] Persons with a disorder of fatty acid oxidation are unable to metabolise fatty acids, which replace carbohydrates as the major energy source on the diet. On the ketogenic diet, their bodies would consume their own protein stores for fuel, leading to ketoacidosis, and eventually coma and death.[37]
That was really interesting and useful information. But I wanted to ask you about what Dom said at time (52min). What does he mean,when he says 1 mml increase is about 10% increase of substrate to the brain? Is that (same glucose amount in brain) + (typical ketone amount in brain)+ and 10% more? Or does it substitute glucose? And if it is so, does the brain use that energy or does it just stay around the brain without being used? I know we can’t know for sure, but it would be helpful if you said what you think. Thanks in advance!

Net carbs are what we track when following a ketogenic diet. This calculation is pretty straightforward. Net Carbs = Total Carbs – Fiber. For example, one cup of broccoli has 6g of total carbs and 2.4g of fiber. That would mean one cup of broccoli has 3.6g of net carbs. We count Net Carbs  because dietary fiber does not have a significant metabolic effect. 


I have never been able to fix the electrolyte loss symptoms I get on the ketogenic diet (heart palpitations, dry mouth, air hunger) by supplementing with electrolytes. Blogosphere says that is just the transition, but mine seem to only get worse over time. I’ve tried about 2 grams of extra potassium, 800 mg extra magnesium, and 3 grams extra salt (in addition to my already liberally salted foods) spread throughout the day. This did not help. Also does eating salt alone cause you to retain water and therefore retain the rest of the electrolytes without supplementing them?
It usually takes three to four days for your body to go into ketosis because you have to use up your body's stores of glucose, i.e., sugar first, Keatley says. Any major diet change can give you some, uh, issues, and Keatley says he often sees patients who complain of IBS-like symptoms and feeling wiped out at the beginning of the diet. (The tiredness happens because you have less access to carbs, which give you quick energy, he explains.)
Here are a few of the most common side effects that I come across when people first start keto. Frequently the issues relate to dehydration or lack of micronutrients (vitamins) in the body. Make sure that you’re drinking enough water (close to a gallon a day) and eating foods with good sources of micronutrients. To read more on micronutrients, click here >
Once inside the mitochondrion, the dominant way that the bound fatty acids are used as fuel in cells is through β-oxidation, which cleaves two carbons off of the acyl-CoA molecule in every cycle to form acetyl-CoA.[24] Acetyl-CoA enters the citric acid cycle, where it undergoes an aldol condensation with oxaloacetate to form citric acid; citric acid then enters the tricarboxylic acid cycle (TCA), which harvests a very high energy yield per carbon in the original fatty acid.[25][26]
^ Freeman JM, Vining EP, Pillas DJ, Pyzik PL, Casey JC, Kelly LM. The efficacy of the ketogenic diet—1998: a prospective evaluation of intervention in 150 children. Pediatrics. 1998 Dec;102(6):1358–63. doi:10.1542/peds.102.6.1358. PMID 9832569. https://web.archive.org/web/20040629224858/http://www.hopkinsmedicine.org/press/1998/DECEMBER/981207.HTM Lay summary]—JHMI Office of Communications and Public Affairs. Updated 7 December 1998. Cited 6 March 2008.
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There are many ways in which epilepsy occurs. Examples of pathological physiology include: unusual excitatory connections within the neuronal network of the brain; abnormal neuron structure leading to altered current flow; decreased inhibitory neurotransmitter synthesis; ineffective receptors for inhibitory neurotransmitters; insufficient breakdown of excitatory neurotransmitters leading to excess; immature synapse development; and impaired function of ionic channels.[7]
3) Cholesterol levels usually go up with inflammation, because inflammation causes damage to the tissues, and cholesterol is manufactured and released in circulation to patch things up. So, again, eating high fat is the best way to drop inflammation; not increase it. My hsCRP are always below 0.1, and most of the time, below detection level. Oxidation of cholesterol causes inflammation; not the other way around. So, your point about inflammation is a non-issue.
I asked James Fell if he had some practical advice on sustainable dieting. “When it comes to weight loss,” he said, “the only thing that matters is caloric deficit. However, quality of diet affects quantity. A higher quality diet is more likely to be one that allows you to eat a lower quantity of calories and still be satisfied. That being said, there are many different ways to find a high-quality diet.”
The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used primarily to treat difficult-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than carbohydrates. Normally, the carbohydrates contained in food are converted into glucose, which is then transported around the body and is particularly important in fueling brain function. However, if little carbohydrate remains in the diet, the liver converts fat into fatty acids and ketone bodies. The ketone bodies pass into the brain and replace glucose as an energy source. An elevated level of ketone bodies in the blood, a state known as ketosis, leads to a reduction in the frequency of epileptic seizures.[1] Around half of children and young people with epilepsy who have tried some form of this diet saw the number of seizures drop by at least half, and the effect persists even after discontinuing the diet.[2] Some evidence indicates that adults with epilepsy may benefit from the diet, and that a less strict regimen, such as a modified Atkins diet, is similarly effective.[1] Potential side effects may include constipation, high cholesterol, growth slowing, acidosis, and kidney stones.[3]
Epilepsy is one of the most common neurological disorders after stroke,[7] and affects around 50 million people worldwide.[8] It is diagnosed in a person having recurrent, unprovoked seizures. These occur when cortical neurons fire excessively, hypersynchronously, or both, leading to temporary disruption of normal brain function. This might affect, for example, the muscles, the senses, consciousness, or a combination. A seizure can be focal (confined to one part of the brain) or generalised (spread widely throughout the brain and leading to a loss of consciousness). Epilepsy can occur for a variety of reasons; some forms have been classified into epileptic syndromes, most of which begin in childhood. Epilepsy is considered refractory (not yielding to treatment) when two or three anticonvulsant drugs have failed to control it. About 60% of patients achieve control of their epilepsy with the first drug they use, whereas around 30% do not achieve control with drugs. When drugs fail, other options include epilepsy surgery, vagus nerve stimulation, and the ketogenic diet.[7]
2) I'm currently using Ketocana and in that section you state "Similar to the BHB salts and MCT’s from the KETO//OS I discuss above, powdered forms of ketones are excellent if you don’t want to completely eliminate carbohydrates or fat or eat copious amounts of fats, but want to simultaneously maintain high levels of blood ketones." – How would eating copious amounts of fat be a negative? Wouldn't that help contribute to a ketogenic state?

Then there’s medium chain triglycerides (MCT’s). Most dietary fat has to be converted into water soluble molecules that then need to enter the liver via your lymph system. Your liver then converts these molecules to fatty acids and ketone bodies. But unlike most other forms of dietary fats, MCT’s can enter your liver directly without having to go through your lymph system. This means that consuming MCT’s gives your body an opportunity to quickly produce ketone bodies.


“Studies have shown that the ability to stick to a diet is more important for long-term success than the type of diet that’s followed,” says Yawitz. “Keto is incredibly restrictive and is particularly tough for those who have frequent social engagements or are prone to carb cravings.” The Mediterranean diet allows you to eat carbs, like as many fruits and veggies as you want, along with whole grains. Not to mention, the Mediterranean diet has been linked to a number of other health benefits, including a lower risk of Alzheimer’s and Parkinson’s disease, certain types of cancer, and heart disease, according to the Mayo Clinic.
But sadly, whether due to government subsidy of high carb foods like corn and grain, funding from big companies like Gatorade and Powerbar, our sugar-addicted Western palates, or the constant (unfounded) fear mongering about saturated fats and heart disease, the type of research that shows these fat-burning and performance benefits of carbohydrate restriction simply get shoved under the rug.
C8 is the rarest MCT found in coconut oil, comprising about 6% of coconut oil. It has potent anti-microbial properties (way more potent than lauric acid) to help you maintain a healthy gut, and it is the fastest MCT to metabolize in the brain. (hence the name Brain Octane). Your liver does not need to process C8, and it only takes the steps for your body to turn it into ATP cellular energy (sugar takes 26 steps). You would need 18 tablespoons of coconut oil to get just one tablespoon of Brain Octane.
The question then is whether your crotch is like your mouth. Not in general, but in the specific case of ketones. That is, when you are on the keto diet, can ketones also accumulate in your crotch area and then subsequently lead to a new smell? Moreover, if you are woman, could ketones be changing the acidity of your vagina, which then may produce an environment more favorable to certain types of microorganisms? Indeed, the smell of your vagina can depend on the composition of microorganisms there. Some odors, like a strong fishy one, can be the result of an overgrowth of certain microorganisms like bacteria, which is the case in bacterial vaginosis.
The keto diet is often called a fad diet. Make no mistake: it is. But unlike other trendy diets, the keto diet is unique because it actually pushes the body into an alternate, natural metabolic state called ketosis. When this happens, you can reliably expect a few negative side effects, notably those that come with the "keto flu." But other side effects emerge only when people implement the keto diet poorly, typically by failing to eat balanced, nutrient-rich foods as a part of a high-fat, low-carb diet.
If you're healthy and eating a balanced diet, your body controls how much fat it burns, and you don't normally make or use ketones. But when you cut way back on your calories or carbs, your body will switch to ketosis for energy. It can also happen after exercising for a long time and during pregnancy. For people with uncontrolled diabetes, ketosis is a sign of not using enough insulin.

Amazing article – gonna have to print it and read it again. To much to break down in one sitting. Thanks Ben – you’ve pulled together so much insight and references that’s given me greater confidence and conviction. I’m 50 and use to be super active and a seasoned athlete but after a few ‘mid life surgical interventions’ I had to find a better way… Ketogenics has been that for me… no more inflammation… I can’t tell you how great it’s been to be pain free! Keep leading from the front.

My question is: what if I want to be in ketosis for all the reasons mentioned in the Life Extension article and because I don't feel a strong urge to eat in between meals when I go lower carb and if I up carb intake I get hungrier more frequently and get urges . . . BUT on the flip side, I don't seem to digest fat all that well(dairy in particular is a no-no) and constipation is an issue and starchy carbs seem to help with that. It's a bit of a catch-22.


A systematic review in 2018 looked at 16 studies on the ketogenic diet in adults. It concluded that the treatment was becoming more popular for that group of patients, that the efficacy in adults was similar to children, the side effects relatively mild. However, many patients gave up with the diet, for various reasons, and the quality of evidence inferior to studies on children. Health issues include high levels of low-density lipoprotein, high total cholesterol, and weight loss.[24]
Normal dietary fat contains mostly long-chain triglycerides (LCTs). Medium-chain triglycerides (MCTs) are more ketogenic than LCTs because they generate more ketones per unit of energy when metabolised. Their use allows for a diet with a lower proportion of fat and a greater proportion of protein and carbohydrate,[18] leading to more food choices and larger portion sizes.[4] The original MCT diet developed by Peter Huttenlocher in the 1970s derived 60% of its calories from MCT oil.[15] Consuming that quantity of MCT oil caused abdominal cramps, diarrhea, and vomiting in some children. A figure of 45% is regarded as a balance between achieving good ketosis and minimising gastrointestinal complaints. The classical and modified MCT ketogenic diets are equally effective and differences in tolerability are not statistically significant.[9] The MCT diet is less popular in the United States; MCT oil is more expensive than other dietary fats and is not covered by insurance companies.[18]
-Cancer: Numerous studies have found that the risk for cancer increases with high blood sugar, which makes sense, since cancer cells feed primarily on glucose. This includes cancers of the endometrium, pancreas, and colon and colorectal tumors. Tim Ferriss recently hosted a fantastic article by Peter Attia about this very issue, and how ketosis may indeed be a potential cancer cure.

Amazing article – gonna have to print it and read it again. To much to break down in one sitting. Thanks Ben – you’ve pulled together so much insight and references that’s given me greater confidence and conviction. I’m 50 and use to be super active and a seasoned athlete but after a few ‘mid life surgical interventions’ I had to find a better way… Ketogenics has been that for me… no more inflammation… I can’t tell you how great it’s been to be pain free! Keep leading from the front.

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But wait, there’s one loophole. Have polycystic ovary syndrome (PCOS)? Then the keto diet may help regulate your periods. “Women with PCOS have high insulin levels, which cause sex hormone imbalances,” notes Yawitz. In a small study published in the journal Nutrition & Metabolism, subjects with PCOS following a ketogenic diet for six months noted improvements in their menstrual cycles — and a small number of women became pregnant, overcoming previous infertility obstacles. “This study was very small, so we can’t make recommendations for all women with PCOS based on its findings,” says Yawitz. “And really, any diet that leads to weight loss should help in PCOS.”
You state that many athletes and very active people could benefit from 100-200g of carbs a day, and be back in ketosis in a few hours. Any particulars on which kind of activities or say how long/many training sessions would benefit from this to balance hormones. I train mma 3-4 days a week and also do lots of hiit and strength training as well. Just trying to see if this is a situation where i would benefit from your suggestions. Thanks!
Hi Gigi, Low carb and keto is about the balance of macronutrients eaten (fat, protein and carbs), not specifically meat or lack thereof. Most people on keto do eat meat, though some people do vegetarian keto. Fat is actually necessary for many body processes. There is no issue for the kidneys with a high fat diet, but if you eat too much protein that isn’t great for the kidneys. It’s a common misconception that keto is high protein (it isn’t). Keto is great for diabetics as it naturally helps stabilize insulin. All of this being said, please know I’m not a doctor and you should consult your doctor on any medical questions or before starting any diet. If you have more questions that aren’t medical questions, I recommend our low carb & keto support group here.
But while carbohydrates can help you have a better workout, go faster, or go longer, this only applies to acute, in-the-moment performance. Once you take a look (which you’re about to do) at the long-term effects of chronic high blood sugar levels, things change drastically. If the damage that you’re above to discover is worth it to you, then you are either mildly masochistic or you value performance much more than health.

Epilepsy is one of the most common neurological disorders after stroke,[7] and affects around 50 million people worldwide.[8] It is diagnosed in a person having recurrent, unprovoked seizures. These occur when cortical neurons fire excessively, hypersynchronously, or both, leading to temporary disruption of normal brain function. This might affect, for example, the muscles, the senses, consciousness, or a combination. A seizure can be focal (confined to one part of the brain) or generalised (spread widely throughout the brain and leading to a loss of consciousness). Epilepsy can occur for a variety of reasons; some forms have been classified into epileptic syndromes, most of which begin in childhood. Epilepsy is considered refractory (not yielding to treatment) when two or three anticonvulsant drugs have failed to control it. About 60% of patients achieve control of their epilepsy with the first drug they use, whereas around 30% do not achieve control with drugs. When drugs fail, other options include epilepsy surgery, vagus nerve stimulation, and the ketogenic diet.[7]
“Given that there is no known detriment to consumption of a high-carbohydrate diet (other than body weight gain due to water retention) and some research reports a benefit, it is recommended that all athletes consume a high-carbohydrate training diet, i.e., at least 60-70% of energy as carbohydrate (7-10 g/kg), and increase this to 65-85% for the few days before competition. Use of a carbohydrate supplement before and during exercise will likely improve performance of intermittent, high-intensity sprints.”
Hi Ben, great article. I have been a keto-adapted athlete for over 2 years, all through nutrition (65/25/10). I have recently discovered UCAN, KetoOS and MAP Aminos. So, here’s my question: If I am going out for a 4-hour ride, and I want to fuel myself just on these supplements and my body’s natural fat stores, how and in what order should I take them? If I take them all together, will the aminos in the KetoOS interfere with MAP Aminos? Or should I just make a mix of the UCAN and KetoOS in 10oz of water and use it to wash back my 6 MAP tablets, 15-mins before my ride? Thanks for your advice!
Ketones are also a cleaner-burning fuel than carbs. They’re burned for energy in the mitochondria, and fewer free radicals (a highly-reactive, short-lived uncharged molecule) are generated when compared to burning glucose.15 What’s more, ketone molecules themselves cause a decrease in production of free radicals,21,22 while also increasing glutathione–a powerful antioxidant protecting against mitochondrial damage induced by free radicals.23
In nondiabetics, ketosis (also called nutritional ketosis) is regulated and controlled in the body so that ketone levels never reach the harmful levels associated with diabetic ketoacidosis. Ketoacidosis is an acute, life-threatening condition that occurs in severely uncontrolled diabetes (mainly type 1) when ketones rise to massive, supranormal levels.
But people who started following the keto diet noticed weight loss for a few reasons: When you eat carbs, your body retains fluid in order to store carbs for energy (you know, in case it needs it). But when you’re not having much in the carb department, you lose this water weight, says Warren. Also, it's easy to go overboard on carbohydrates—but if you're loading up on fat, it may help curb cravings since it keeps you satisfied.

Those issues can be part of what's known as the “keto flu,” Warren says. Other side effects of the keto diet, all of which are tied to carb withdrawal, can include lightheadedness, nausea, mental fog, cramps, and headaches, in addition to tiredness. Luckily, the keto flu doesn't usually last more than a week—which is coincidentally about when people start to see the number on the scale go down, says Warren.
The ketone bodies are possibly anticonvulsant; in animal models, acetoacetate and acetone protect against seizures. The ketogenic diet results in adaptive changes to brain energy metabolism that increase the energy reserves; ketone bodies are a more efficient fuel than glucose, and the number of mitochondria is increased. This may help the neurons to remain stable in the face of increased energy demand during a seizure, and may confer a neuroprotective effect.[56]
Keto is short for ketogenic. If you didn’t already know, it’s a high-fat, low-carb diet. The goal of the ketogenic diet is to get your body into a “ketogenic state,” or a physiological state in which your body is not burning carbohydrates -- which break down to glucose -- but an alternative energy source called ketones, which are produced by the liver when your body is depleted of glucose. Ketones are formed from fat stores. In order for your body to start producing ketones, it needs to first run out of glycogen stores. After you deprive your body of carbs, it takes a bit of time for the glucose to clear out.
Burns fat: You can drop a lot of weight — and quickly — on the keto diet.[3] Ketones suppress ghrelin — your hunger hormone — and increase cholecystokinin (CCK), which makes you feel full.[4] Reduced appetite means it’s easier to go for longer periods without eating, which encourages your body to dip into its fat stores for energy. Learn more here about the keto diet and weight loss. 
Keto-adaption is a complex set of metabolic processes in which the body shifts from using primarily glucose for energy to using largely ketones and fat for energy. Achieving ketosis doesn’t mean the body is maximizing the use of these ketones; it takes longer than a few days for the body to get used to burning fat and ketones as its predominant fuels.
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