And what I’m writing has nothing to do with taking supplements to induce ketosis or whatever. I believe these things are covered in Volek & Phoney’s book The Art and Science of Low Carb Living, which I would have thought you to be very familiar with. The iodine stuff you can read about in Iodine, Why We Need, Why We Can’t Live Without It by Brownstein.


^ Ringberg TM, White RG, Holleman DF, Luick JR (1981). "Body growth and carcass composition of lean reindeer (Rangifer tarandus tarandusL.) from birth to sexual maturity" (PDF). Canadian Journal of Zoology. 59 (6): 1040–1044. doi:10.1139/z81-145. ISSN 0008-4301. Body growth and carcass composition were measured in lean reindeer during the juvenile growth period between birth and 3 years of age. Mean carcass weight in these lean reindeer was 56 ± 4% of body weight and the deposition of body muscle and bone mass was linearly correlated with body weight after the 1st month of age. The weight of the brain relative to body weight and carcass weight declined, while the relative changes in heart, liver, kidneys, parotid glands, and tissues of the gastrointestinal tract were small after the neonatal period. The extractable fat content in carcasses increased from 4.4 to 11.4% of wet weight or approximately 100 g fat at birth and 3.5 kg fat in adult reindeer. Fat-free dry matter represented a constant percentage (18–20%) of wet carcass weight independent of body weight after the neonatal period, while a significant inverse relationship between carcass fat and body water was found.
Ketosis is a nutritional process characterised by serum concentrations of ketone bodies over 0.5 mM, with low and stable levels of insulin and blood glucose.[1][2] It is almost always generalized with hyperketonemia, that is, an elevated level of ketone bodies in the blood throughout the body. Ketone bodies are formed by ketogenesis when liver glycogen stores are depleted (or from metabolising medium-chain triglycerides[3]). Ketones can also be consumed in exogenous ketone foods and supplements.
Nutritional ketosis is a natural metabolic state in which your body adapts to burning fat rather than carbohydrates as its primary fuel. It is clinically proven to directly reduce blood sugar (as measured by HbA1c), improve insulin sensitivity (as measured by HOMA-IR) and reduce inflammation (as measured by white blood cell count and CRP). Nutritional ketosis can be induced by following a ketogenic diet. Learn more in our FAQ below!
The bottom line is that there have not been enough scientific studies, especially longer term ones, to really determine all the potential risks and benefits of the keto diet. Many of the claims out there on the Internet, social media, or television in either direction are anecdotal, meaning that they are individuals telling stories about what has supposedly been their experiences. Take everything you hear that is not supported by scientific evidence with a grain of salt (but not too much salt because too much can be bad for you.)
Perhaps you fall into the category of Olympic athletes who would dope with damaging drugs, even if they knew it would kill them. However, if you desire a long, high-quality life, you don’t want to be a washed up ex-exerciser with diabetes, or you don’t want to experience joint, nerve and brain inflammation, damage and degradation, you may need to adjust your lens.
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Might not be nutritional. Could be a training issue. Could be fascial. Could be neurotransmitter. If you're taking 1 serving of UCAN perhaps you need two. Not sure of ht, body wt, etc. I'd be happy to help you via a personal one-on-one consult. Just go to https://bengreenfieldfitness.com/coaching. and then choose a 20 or 60 minute consult, whichever you'd prefer. I can schedule ASAP after you get that.

I just discovered your site and have been thoroughly enjoying many of the articles and appreciate that you get so in depth in your explanations. I’m in my late 40’s and, while not an extreme endurance athlete, I am moderately active with 18-20 mile rides 3x a week as well as some boxing and body weight resistance (push up, pull up, etc) mixed in. I’ve generally been paleo and stick to quality macros for the most part (grass fed meats/dairy, organic veg and oils) and zero supplements. I recently started following keto (after reading this article) about 10 days ago and things seem good thus far. I do, however, want to avoid any of the negative side effects you mention and also not lose any lean muscle. I’m currently about 174 lbs, 5’8″ and about 19% bodyfat – I’m taking in about 95g protein, 130g fat and <20g net carbs. I'm eating all quality – wild salmon, grass fed beef, pastured eggs, coconut oil, Brain Octane and Grass fed butter in coffee, sardines, etc. With a smattering of organic veg, but it seems real easy to bust through the carb barrier. *I'M ALSO TAKING KETOCANA PRE-WORKOUT* and I notice this is keeping me going throughout a ride or the gym.


A high-fat diet also trains your body to burn even more fat during exercise, even at high intensities. Fat is released faster and in greater amounts from your storage adipose tissue and transported more quickly into your muscles and mitochondria. Your muscles also store more energy as fat and use this fat-based fuel more efficiently and quickly. Even more interestingly, a high-fat diet can cause a shift in the gene expression that codes for specific proteins that increase fat metabolism – and create very similar adaptations to exercise itself. So the mere act of shifting primary fuel intake from carbohydrates to fat begins to make you more “fit”, even if you’re not exercising.
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]

So in the end, I ordered 1kg of pure BHB Magnesium from a supplier in China and I will be developing my own Ketone product with 30 servings as a lower price than all the competitors, and with more Magnesium, and Calcium in it than Sodium so that it tastes the best and actually helps with weight loss (which Magnesium is proven to do at the right amount). What the companies don’t tell you is that actually Sodium BHB is the cheapest, then Calcium BHB and then Magnesium BHB to source so I would be interested in knowing if what you wrote is actually true or just an excuse to make the product cheaper. Probably a mix of both.

Thanks for all of the great info!! I have Hashimoto’s and would really like to try a high fat/low carb diet. You mentioned that this might not be a good option for people with thyroid issues. How do you recommend I modify my diet to lose weight taking into consideration the Hashimoto’s. I take Westhroid, a non-synthetic thyroid supplement to help with my sluggish thyroid. Thanks so much for any advice you can give me. :)


No offense brother, but this whole article is a big selling advertisement. The health benefits of a “low – carb, high – fat” diet are well known and proven. I directly blame nutritionists, like yourself, for the fact that ~70% of American is considered obese now, not fat, obese. And the fact that Heart Disease is the number 2 killer in America now, second only to cancer.


I was thinking of buying exogenous ketones for my mother. She plays golf daily but gained some weight as of late. My mother does not want to do the diet but I was thinking this might help her with energy and losing weight. Another person told me it would help her. But then I got to thinking, if she went into Ketosis, then wouldn’t she get the keto flu rather than get energy and mental clarity? Would I need to tell her to take it everyday?
Urine test for diabetes: What you need to know Urine tests for diabetes check for protein, ketones, and glucose. They are frequently used for diagnosing and monitoring diabetes, and to assess people who are experiencing symptoms, such as fatigue or nausea. Depending on the results, recommendations may be given about medication or lifestyle changes that could help. Read now
Ideally, you combine supplemental ketones with a relatively low carb diet, especially if metabolic efficeincy is important to you. HOWEVER, you can achieve most of the benefits of ketosis aside from the fat burning efficiency by using exogenous ketones. So it all depends on how lean you are, what's important to you from a performance vs. fat loss standpoint, etc.
The reason purity matters is that C17 is a byproduct of most MCT oil production processes, and it, along with C6, is a major cause of throat burning and gut irritation. Most MCT’s on the market are manufactured via chemical and solvent based refining, which involves using chemicals like hexane and different enzymes and combustion chemicals, such as sodium methoxide. But ideally, you should get an MCT oil that is made using triple steam distillation in a non-oxygen atmosphere to avoid lipid oxidation and create a purer end-product.
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!
It also means that if you’re a very active athlete or exercise enthusiast and you’re following “trickle-down” advice from the sedentary or less active ketosis experts to eat less than 40g of carbs per day, you’re making a big mistake when it comes to your hormonal balance, and you need to up your carbohydrate intake to 100-200g of carbs per day. You’d be surprised at how easy it is (if you’re a very active person) to stay in ketosis on this level of carbohydrate intake. Go ahead. Do Ketonix breath testing to prove me wrong. You can eat boatloads of carbohydrates at night and be back in ketosis within just two to three hours. When you combine that with the cutting-edge tricks you’re about to learn, you’ll find that you can toss hormonal issues out the window, get into ketosis, have your cake, and eat it too. Literally.

While it is believed that carbohydrate intake after exercise is the most effective way of replacing depleted glycogen stores,[72][73] studies have shown that, after a period of 2–4 weeks of adaptation, physical endurance (as opposed to physical intensity) is unaffected by ketosis, as long as the diet contains high amounts of fat, relative to carbohydrates.[74] Some clinicians refer to this period of keto-adaptation as the "Schwatka imperative" after Frederick Schwatka, the explorer who first identified the transition period from glucose-adaptation to keto-adaptation.[75]
What is the link between ketones and diabetes? Ketone is a chemical produced by the body when fats are broken down for energy. Ketone testing is important for people with diabetes, because high levels can lead to diabetic ketoacidosis (DKA), when acid levels become too high in the blood and the person loses consciousness. Find out when and why to do ketone testing. Read now
First reported in 2003, the idea of using a form of the Atkins diet to treat epilepsy came about after parents and patients discovered that the induction phase of the Atkins diet controlled seizures. The ketogenic diet team at Johns Hopkins Hospital modified the Atkins diet by removing the aim of achieving weight loss, extending the induction phase indefinitely, and specifically encouraging fat consumption. Compared with the ketogenic diet, the modified Atkins diet (MAD) places no limit on calories or protein, and the lower overall ketogenic ratio (about 1:1) does not need to be consistently maintained by all meals of the day. The MAD does not begin with a fast or with a stay in hospital and requires less dietitian support than the ketogenic diet. Carbohydrates are initially limited to 10 g per day in children or 20 g per day in adults, and are increased to 20–30 g per day after a month or so, depending on the effect on seizure control or tolerance of the restrictions. Like the ketogenic diet, the MAD requires vitamin and mineral supplements and children are carefully and periodically monitored at outpatient clinics.[48]
Would be curious to receive feedback on any of the above! And if anyone is interested in more info on my future Ketone product which will taste great, have 11.7g of BHB, 30 servings and priced lower than all the competitors, then message me on FB under Rhys Kabra, or email [email protected] for status updates on the upcoming new Brand of Ketone products! :)
A high-fat diet also trains your body to burn even more fat during exercise, even at high intensities. Fat is released faster and in greater amounts from your storage adipose tissue and transported more quickly into your muscles and mitochondria. Your muscles also store more energy as fat and use this fat-based fuel more efficiently and quickly. Even more interestingly, a high-fat diet can cause a shift in the gene expression that codes for specific proteins that increase fat metabolism – and create very similar adaptations to exercise itself. So the mere act of shifting primary fuel intake from carbohydrates to fat begins to make you more “fit”, even if you’re not exercising.

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. 
On the ketogenic diet I feel very shaky/anxious from when I wake up til about noon. Eating doesn’t really help. It could be electrolyte related but seems possibly more related to excess cortisol/adrenaline as noon is also when I start to crash and get tired on a more normal diet, and because those 3 am awakenings that worsen simultaneously in ketosis seem to also have to do with HPA axis stuff. Does this side effect potentially also have to do with my fasting blood sugar being elevated?
Question: I have recently done my 23&me DNA test and have also put my info into AthletiGen. I’m curious about your thoughts about high fat/low carb diet in context of this info. My test says I am ‘2x more likely to loose weight on a low fat diet’, and that I have ‘normal sensitivity to weight gain due to saturated fat intake/and unsaturated fat intake’, & ‘likely to eat normal amounts of carbs’! All interesting but in the ketosis context, I took this to mean that eating high fat/low carb would not be of greatest benefit to me?! (I have tried getting into ketosis prior to all the new supps, for about 3 months, and I couldn’t get in to it (tested w/ blood finger prick) and didn’t feel great). Which leads me to wonder what Macro ratio would be best, as I’m also a endo-meso)!
Ketosis is an energy state that your body uses to provide an alternative fuel when glucose availability is low.  It happens to all humans when fasting or when carbohydrate intake is lowered.  The process of creating ketones is a normal metabolic alternative designed to keep us alive if we go without food for long periods of time. Eating a diet low in carb and higher in fat enhances this process without the gnawing hunger of fasting.
“To achieve the relatively high rates of intake (up to 90 grams/hour) needed to optimize results in events lasting longer than three hours, athletes should practice consuming carbohydrates during training to develop an individual strategy, and should make use of sport foods and drinks containing carbohydrate combinations that will maximize absorption from the gut and minimize gastrointestinal disturbances.”
I’ll warn you: when you first start using BHB salts like KetoCaNa, it can cause some temporary GI upset until you get acclimated to use. For me, this manifested in just a little bit of gas and bloating that subsided after about one week of use. Additionally, you should know that this product contains salt, so it counts as part of your daily salt intake.
If you want to make some enemies very quickly, just jump on to social media and say "the keto diet stinks." Because there are certainly a number of people who swear by the keto diet. Some of them will even swear at you if you say anything bad about the diet. Supporters of the diet claim that the keto diet will help lose weight relatively quickly, clear your mind, make you feel better, and even clear up your acne, because you no longer are taking in carbohydrates that "cause inflammation." People who question the diet have raised concerns about whether maintaining such a high fat diet is effective and healthy in long run. After all, high fat diets could raise the risk of various chronic medical conditions such as heart disease and cancer.
In Asia, the normal diet includes rice and noodles as the main energy source, making their elimination difficult. Therefore, the MCT-oil form of the diet, which allows more carbohydrate, has proved useful. In India, religious beliefs commonly affect the diet: some patients are vegetarians, will not eat root vegetables or avoid beef. The Indian ketogenic diet is started without a fast due to cultural opposition towards fasting in children. The low-fat, high-carbohydrate nature of the normal Indian and Asian diet means that their ketogenic diets typically have a lower ketogenic ratio (1:1) than in America and Europe. However, they appear to be just as effective.[54]

The keto diet changes the way your body converts food into energy. Eating a lot of fat and very few carbs puts you in ketosis, a metabolic state where your body burns fat instead of carbs for fuel. When your body is unable to get glucose from carbs, your liver converts fatty acids from your diet into ketones, an alternative source of energy. Burning ketones in place of glucose reduces inflammation and spurs weight loss.[1]
^ Ketogenic "eggnog" is used during induction and is a drink with the required ketogenic ratio. For example, a 4:1 ratio eggnog would contain 60 g of 36% heavy whipping cream, 25 g pasteurised raw egg, saccharin and vanilla flavour. This contains 245 kcal (1,025 kJ), 4 g protein, 2 g carbohydrate and 24 g fat (24:6 = 4:1).[17] The eggnog may also be cooked to make a custard, or frozen to make ice cream.[37]

Note: Because you'll be excluding some major food groups on the keto diet (grains, many fruits) you should definitely think about taking a multivitamin—especially one that contains folic acid, which helps your body make new cells and is often found in enriched breads, cereals, and other grain products, says Julie Upton, R.D., cofounder of nutrition website Appetite for Health.


Fairly recently, the diet was introduced as a weight-loss diet by an Italian professor of surgery, Dr. Gianfranco Cappello of Sapienza University in Rome. In his 2012 study, about 19,000 dieters received a high-fat liquid diet via a feeding tube inserted down the nose. The study showed an average weight loss of more than 20 pounds in participants, most of whom kept it off for at least a year. The researchers reported a few minor side effects, like fatigue.
I’ve been experimenting with MCT Oil Brain Octane. I have one questions. I’ve been eating about 20 – 25 gr. of carbs per day on a high fat, medium protein diet. I’m measuring ketones in the morning before taking the MCT and after. I’ve been taking btw. 1-2 tbsp of MCT Brain Octane with butter (Bulletproof coffee) – I measure again after 30 min., 1hr, 2 hrs. and don’t see a raise in my blood ketones. Anything I’m missing, would love to hear your thoughts, Ben. – Thx I’m measuring with Precision Xtra and Ketonix Red.
After 2 years in ketosis suddenly I find my blood glucose has risen to high levels even while in ketosis. I thought it was the dawn phenomenon, stress hormones like cortisol but now I am beginning to think I am eating too many exongenous keytones like too much MCT oil? I am not taking exogenous keytone supplements but wondering if too much oil/ fat in the diet generates exogenous keytones which inhibits the livers production of endogenous keytones. I have read if the liver is producing endogenous keytones it is not at the same time producing glucose through gluconeogenisis?

So far in my experiments I don’t find that “fake ketosis” induced via taking brain octane oil to get purple urine strips (while eating about 70 grams of total carbs/day) has the same satiating, craving-busting effects for me as “real ketosis” (eating under 50 grams of total carbs/day). In “fake ketosis” I still feel the need to eat something every 2-3 hours and constantly crave carbs. Does anyone else on a supplemental ketone diet experience this or are they able to eat less frequently?

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.

In other words, I personally found that while following “strict ketosis”, things became eerily similar to the days in college when I was a competitive bodybuilder pursuing sub-3% body fat percentages. I simply wasn’t the most fun guy to hang out with in social situations due to my extreme dietary restrictions, the intense self-control became nearly exhausting, and when I traveled, I missed out on many culinary experiences, such as homemade ravioli in Rome, freshly baked crostinis in the Basque regions of Spain, and Korean rice bowls in Seoul.
When you burn key tones as a funeral, whether they are from a supplement or whether they are the ones that your body makes, you do indeed become more efficient utilizing ketones. So that is one advantage. You are correct in that if you simply use these and you do not restrict carbohydrate intake then you're not going to get quite as much benefit. I am a fan of combining these with intermittent fasting, MCT oil, and a high-fat diet.
When your body burns its stores of fat, it can be hard on your kidneys. And starting a ketogenic diet -- or going back to a normal diet afterward -- can be tricky if you’re obese because of other health issues you’re likely to have, like diabetes, a heart condition, or high blood pressure. If you have any of these conditions, make diet changes slowly and only with the guidance of your doctor.
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]
No-sugar diet plan: What you need to know Eliminating sugar from the diet can help prevent weight gain, diabetes, heart disease, and other problems. Whether cutting sugar out of the diet completely or simply cutting back, we have eight important tips for following a no-sugar diet, and some advice about fruits and other natural foods that contain sugar. Read now

You’re transitioning. Your body is equipped to process a high intake of carbs and a lower intake of fat. Your body needs to create enzymes to be able to do this. In the transitional period, the brain may run low on energy which can lead to grogginess, nausea, and headaches. If you’re having a large problem with this, you can choose to reduce carb intake gradually.
On a low carb or ketogenic diet my fasting blood sugar is 90-120. I think it may get higher the lower carb I go. Most internet sources say don’t worry about it, worry about your Ha1c. Is this insulin resistance? Anyone have better information? If I do a water fast my morning blood sugar will go down and down each day, til it reaches about 50 in 4 days. But as soon as I start eating it pops right back up.
The second type of cellular fuel comes from fat and fat metabolism products called ketone bodies.   The average sized human body can store hundreds of thousands of calories in the form of fat, so we could say that this system of energy is almost unlimited, depending on how long one goes without food.  Eventually, it would get used up, but people have been known to fast for months and live through it.
Lemons are also keto-friendly, so go ahead and add a spritz of lemon juice to your ice water. One typical lemon wedge has about 0.5  g of net carbohydrates and only 0.2 g of sugar. The fruit also offers  3.7 mg of vitamin C, which is 6.2 percent of the DV. Lemon water contains antioxidants that fight free radicals, and it also promotes healthy digestion, according to the Cleveland Clinic.
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