Variations on the Johns Hopkins protocol are common. The initiation can be performed using outpatient clinics rather than requiring a stay in hospital. Often, no initial fast is used (fasting increases the risk of acidosis, hypoglycaemia, and weight loss). Rather than increasing meal sizes over the three-day initiation, some institutions maintain meal size, but alter the ketogenic ratio from 2:1 to 4:1.[9]
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!
Weight loss benefits ushered the keto diet into the spotlight. That’s how most people have likely heard about ketones, a fuel source created naturally by the body when burning fat. But more and more research points to diverse applications of ketones in the blood outside of just fat loss, from improved endurance performance to the treatment of medical conditions like epilepsy.
Hi Ben – Great article. I had trouble at the end figuring out if you were now eating high fat (60-80% of calories), or if you went back to something closer to 50% fat calories and higher carbs and are using exogenous ketones to get int ketosis when needed. Are you doing any carbs at night or a refeed, or just having higher carbs on most days? Thanks
If you’re serious about maximizing the benefits of ketosis, then forego coconut oil, MCT liquid oil, olive oil, etc. and instead use Brain Octane as your oil of choice for recipes like bulletproof coffee, or in teas, salad dressings, or as a sushi or entrée flavor enhancer. For a slightly less expensive, but not quite as effective form of MCT, use XCT oil.
Hello, I have a quick question. I’ve been on keto since March 2017. Already lost about 45 pounds, down to 140 at 5’7 and about 16.4% fat. I take a magnésium cap each morning to be sure I got enough and eat at least 1 serving of baby spinach a day with olive oil or fatty dressing that have no carbs. My last meal is always between 5 and 9 pm (mostly around 6) and I don’t eat back before 12pm the next day on week days and not before next dîner on week end. Fasting isn’t something new to me and when I read it help getting in ketosis I continued.

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.
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.
On the ketogenic diet, carbohydrates are restricted and so cannot provide for all the metabolic needs of the body. Instead, fatty acids are used as the major source of fuel. These are used through fatty-acid oxidation in the cell's mitochondria (the energy-producing parts of the cell). Humans can convert some amino acids into glucose by a process called gluconeogenesis, but cannot do this by using fatty acids.[57] Since amino acids are needed to make proteins, which are essential for growth and repair of body tissues, these cannot be used only to produce glucose. This could pose a problem for the brain, since it is normally fuelled solely by glucose, and most fatty acids do not cross the blood–brain barrier. However, the liver can use long-chain fatty acids to synthesise the three ketone bodies β-hydroxybutyrate, acetoacetate and acetone. These ketone bodies enter the brain and partially substitute for blood glucose as a source of energy.[56]
A computer program such as KetoCalculator may be used to help generate recipes.[47] The meals often have four components: heavy whipping cream, a protein-rich food (typically meat), a fruit or vegetable and a fat such as butter, vegetable oil, or mayonnaise. Only low-carbohydrate fruits and vegetables are allowed, which excludes bananas, potatoes, peas, and corn. Suitable fruits are divided into two groups based on the amount of carbohydrate they contain, and vegetables are similarly divided into two groups. Foods within each of these four groups may be freely substituted to allow for variation without needing to recalculate portion sizes. For example, cooked broccoli, Brussels sprouts, cauliflower, and green beans are all equivalent. Fresh, canned, or frozen foods are equivalent, but raw and cooked vegetables differ, and processed foods are an additional complication. Parents are required to be precise when measuring food quantities on an electronic scale accurate to 1 g. The child must eat the whole meal and cannot have extra portions; any snacks must be incorporated into the meal plan. A small amount of MCT oil may be used to help with constipation or to increase ketosis.[37]
So which MCT to pick? Brain Octane (pure C8) provides the fastest rise in ketones and burns the cleanest, with minimal gut irritation. XCT oil is more affordable but works more slowly with less direct cognitive effects. The capric acid C10 in XCT Oil doesn’t break down into ketones as quickly as pure caprylic C8, but capric acid C10 is more affordable, so you can save money by going with the XCT oil. XCT oil still goes to brain energy, just not as quickly as Brain Octane. Both can be used for energy without processing by the liver, unlike many other fats and oils.
As insulin levels plummet from carb-cutting, more water is flushed out, along with excess sodium (in contrast, excess insulin from carbs causes sodium and water retention).4 In some people, dehydration contributes to constipation, which can also result from avoiding fiber-rich carbohydrate foods. While less common, diarrhea or loose bowels can be triggered by a number of factors including too much or too little fat, dairy intolerance, or changes in gut flora. 
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.
Basically, the proven science is in the pudding. A highly cited low-carb study from The New England Journal of Medicine concludes with the statement, “The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year.” The study mentions health benefits from the low carb diet, of course, but that it’s largely unsustainable.

^ 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.

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!
Net carbs is simply total carbs minus fiber and non-digestible sugar alcohols, like erythritol. (This doesn’t apply to high glycemic sugar alcohols, like maltitol.) We don’t have to count fiber and certain sugar alcohols in net carbs, because they either don’t get broken down by our bodies, are not absorbed, or are absorbed but not metabolized. (Read more about sugar alcohols here.)

Now, there a few things you should know before you begin using KETO//OS. First, ketones naturally act as a diuretic, so you lose salt, potassium, calcium and magnesium, and it is generally encouraged to increase sodium intake with ketones. That’s why there is extra sodium added to KETO//OS. The combination of BHB with sodium also acts as a bit of a buffer to buffer natural ketone acidity.
Yes, they're technically a fruit, but we think olives deserve a shout-out all of their own, since they're also a great source of healthy fats and are one of a few keto-approved packaged foods. Plus, they're a great source of antioxidants, will satisfy your craving for something salty, and are blissfully low-carb. “About a palm's worth only has 3 grams of net carbs,” Sarah Jadin, RD, told Health in a previous interview.
“Loss of muscle mass as we age has a number of serious consequences,” notes Clark. “Muscle is metabolically active and helps boost daily energy expenditure and mitigate age-related weight gain.” Losing muscle mass can also decrease functional strength and heighten the risk of falls, notes Clark. Falls are the top cause of death from injury in older populations, according to the Institute of Medicine Division of Health Promotion and Disease Prevention.

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.)


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.)
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]
^ 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]
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?
What would your advice be to a high raw vegan who wants to try an HRV keto diet? The supps you recommended above look vegan, but aren’t the results based on those of omnis? Would they work the same way on vegans? Also I heard you mention in the recent Keto Summit that SE Asians need a little more carb and I happen to be one. I’m a petite 39-YO female and I’ve been raw for the past 11 years. I have been practicing intermittent fasting in the last 7 years and try to eat only twice a day. Up to how many grams of carbs can I consume to get into ketosis?
Keto breath, on the other hand, is less of a side-effect and more of a harmless inconvenience (your breath literally smells like nail polish remover). Basically, when your body breaks down all that extra fat on the keto diet, it produces ketones—one of which is the chemical acetone, Keatley previously told WomensHealthMag.com. (Yes, the same stuff that's in nail polish remover.)
Strawberries are another delicious, sweet, and filling fruit that you can eat in moderation on the keto diet. A ½-cup serving of sliced strawberries contains about 4.7 g of net carbs and 4.1 g of sugar. As there are only 27 calories in the aforementioned serving, you can eat strawberries raw, add a few pieces to your cereal, or blend a handful into a small low-carb smoothie. Strawberries also have antioxidant and anti-inflammatory benefits, per a study published in February 2010 in the Journal of Medicinal Food. The same ½ cup provides 48.8 mg of vitamin C (81.3 percent DV), 127 mg of potassium (2.7 percent DV), and 20 micrograms of folate (5 percent DV).
For patients who benefit, half achieve a seizure reduction within five days (if the diet starts with an initial fast of one to two days), three-quarters achieve a reduction within two weeks, and 90% achieve a reduction within 23 days. If the diet does not begin with a fast, the time for half of the patients to achieve an improvement is longer (two weeks), but the long-term seizure reduction rates are unaffected.[44] Parents are encouraged to persist with the diet for at least three months before any final consideration is made regarding efficacy.[9]
The Keto diet emphasizes weight loss through fat-burning. The goal is to quickly lose weight and ultimately feel fuller with fewer cravings, while boosting your mood, mental focus and energy. According to Keto proponents, by slashing the carbs you consume and instead filling up on fats, you safely enter a state of ketosis. That’s when the body breaks down both dietary and stored body fat into substances called ketones. Your fat-burning system now relies mainly on fat – instead of sugar – for energy. While similar in some ways to familiar low-carb diets, the Keto diet’s extreme carb restrictions – about 20 net carbs a day or less, depending on the version – and the deliberate shift into ketosis are what set this increasingly popular diet apart.

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.”
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]

Hi Maya. I LOVE your site!! Interesting, informative with fab recipes and ideas. Hubby and I have just started eating low carb and I have to say, we are not finding it too difficult and I already feel sooo much better!! I find the hardest part is choosing low carb veg, I feel as if we are not eating enough. Any suggestions on how to get more veggies into our diet?
Longer-term ketosis may result from fasting or staying on a low-carbohydrate diet (ketogenic diet), and deliberately induced ketosis serves as a medical intervention for various conditions, such as intractable epilepsy, and the various types of diabetes.[6] In glycolysis, higher levels of insulin promote storage of body fat and block release of fat from adipose tissues, while in ketosis, fat reserves are readily released and consumed.[5][7] For this reason, ketosis is sometimes referred to as the body's "fat burning" mode.[8]
"The keto diet is primarily used to help reduce the frequency of epileptic seizures in children. While it also has been tried for weight loss, only short-term results have been studied, and the results have been mixed. We don't know if it works in the long term, nor whether it's safe," warns registered dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women's Hospital.
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