In addition, most studies that compare carbohydrate utilization with fat utilization fail to take into account the fact that full “fat adaptation” that allows you to gain all the benefits of using fat as a fuel actually takes time – often more than four weeks – and up to a couple years. But since most studies that compare fat and carbohydrate burning are short-term, you rarely see the benefits of this kind of fat adaptation actually fleshed out in research. Instead, the average research participant begins the study in a non-fat adapted state, gets either a high fat or high carb diet, then launches into exercise. But in an ideal study, that person would have followed either a high-fat or high-carb diet for many months before getting their fat burning capability investigated.

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“When you start the keto diet, you lose sodium and other electrolytes in the urine due to reductions in insulin,” says Yawitz. “This is a major contributor to symptoms of keto flu.” So it’s important to replenish sodium through the diet, especially if you exercise or sweat a lot. “This can help ward off more serious side effects that are seen with long-term sodium deficiencies,” says Yawitz. These include lethargy and confusion — and in extreme cases, seizures, coma, and death, according to the Mayo Clinic.
My keto journey began with chicken and avocado, like many high-fat brethren before me, until I eventually found the paleo cookbooks and created a little diet-friendly life for myself, devoid of family party-friendly foods but productive and communal in its own way. I was joining the online forums. I was reading studies about the health benefits of keto. I was drinking the bone-broth Kool-Aid, believing my fasting states and butter coffee were catapulting me towards some sort of psychophysiological excellence. I lost around 15lbs in 2015 because I didn’t allow myself most of the foods I usually “overdid” and was motivated not only by the progress but by the exclusive, cultish energy of ketosis. We were not the Google diet generation -- we were Google scholar. We treated epilepsy, after all, and our fearless keto leaders preached the Good News to all who would listen, then verbally abused well-meaning bloggers and medical professionals who suggested that extreme dieting might be unhealthy and unsustainable. Amen?
The original therapeutic diet for paediatric epilepsy provides just enough protein for body growth and repair, and sufficient calories[Note 1] to maintain the correct weight for age and height. The classic therapeutic ketogenic diet was developed for treatment of paediatric epilepsy in the 1920s and was widely used into the next decade, but its popularity waned with the introduction of effective anticonvulsant medications. This classic ketogenic diet contains a 4:1 ratio by weight of fat to combined protein and carbohydrate. This is achieved by excluding high-carbohydrate foods such as starchy fruits and vegetables, bread, pasta, grains, and sugar, while increasing the consumption of foods high in fat such as nuts, cream, and butter.[1] Most dietary fat is made of molecules called long-chain triglycerides (LCTs). However, medium-chain triglycerides (MCTs)—made from fatty acids with shorter carbon chains than LCTs—are more ketogenic. A variant of the classic diet known as the MCT ketogenic diet uses a form of coconut oil, which is rich in MCTs, to provide around half the calories. As less overall fat is needed in this variant of the diet, a greater proportion of carbohydrate and protein can be consumed, allowing a greater variety of food choices.[4][5]
^ Bechtel PJ (2 December 2012). Muscle as Food. Elsevier Science. pp. 171–. ISBN 978-0-323-13953-3. Retrieved 19 May 2014. Freezing does stop the postmortem metabolism but only at about −18ºC and lower temperatures. Above −18ºC increasing temperatures of storage cause an increasing rate of ATP breakdown and glycolysis that is higher in the comminuted meat than in the intact tissue (Fisher et al., 1980b). If the ATP concentration in the frozen tissue falls below ~ 1 µmol/g no contraction or rigor can occur because they are prevented by the rigid matrix of ice.

Note: Are you a vegetarian or vegan and want to go on a ketogenic diet? It’s still possible! Just keep in mind that the dietary restrictions can sometimes be a little bit intense. Make sure to plan ahead and prepare to aid your success. To help out, we’ve published articles (with 7 day meal plans included) for both the vegetarian ketogenic diet and the vegan ketogenic diet.


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]
In the US especially, coconut oil and MCT oil manufacturers are legally allowed to claim that lauric acid is an MCT because chemists named it that way, even though it does not act like other true biological MCT oils. If you are relying on plain coconut oil or “MCT-labeled” oil to get enough useful MCTs, think again and check the label: odds are you’re getting very few of the potent, ketogenic shorter chain MCTs (also known as “C8” and “C10”), and instead getting mostly cheaper but ineffective lauric acid.

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]

Physical or mental fatigue during workouts (or while you’re sitting at your office) is caused by the low blood glucose that occurs as your carbohydrate fuel tank approaches empty (also known as the infamous “bonk”, which is awesomely demonstrated in this funniest running cartoon I’ve ever seen). Because it is generally (and sadly) accepted as orthodox knowledge that the human body can’t burn fat as a reliable fuel source – especially when you’re exercising for long periods of time or at high intensities – nearly every shred of nutrition science is simply looking for ways to somehow increase the size of your carbohydrate fuel tank and hack the body to allow it to store more carbs or absorb carbs more quickly.
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.
This article really bothers me in that if you do a few incorrect things with this diet, it will actually do more harm than a full carb diet. I have been in ketosis for a month or so but to what detriment? Based on the “ketosis darkside” list you highlighted, i could be doing any or all of these without realising. Could i share with you my meal plans and see if in your opinion they are beneficial and healthy or if im digging myself an early grave?
During the 1920s and 1930s, when the only anticonvulsant drugs were the sedative bromides (discovered 1857) and phenobarbital (1912), the ketogenic diet was widely used and studied. This changed in 1938 when H. Houston Merritt, Jr. and Tracy Putnam discovered phenytoin (Dilantin), and the focus of research shifted to discovering new drugs. With the introduction of sodium valproate in the 1970s, drugs were available to neurologists that were effective across a broad range of epileptic syndromes and seizure types. The use of the ketogenic diet, by this time restricted to difficult cases such as Lennox–Gastaut syndrome, declined further.[10]
I'm constantly on the lookout for low-carb diet and ketosis friendly option that allow hard charging athletes, especially athletes who have glycolytic, high-intensity demands during sport, to get a “slow bleed” of carbohydrate into their body. For example, “UCAN Superstarch” is one such option, but, unfortunately, I've found that many athletes and exercise enthusiasts tend to get gastric distress or excessive fermentation from that slow-release starch.
Selecting the right food will be easier as you become accustomed to the Keto approach. Instead of lean meats, you’ll focus on skin-on poultry, fattier parts like chicken thighs, rib-eye steaks, grass-fed ground beef, fattier fish like salmon, beef brisket or pork shoulder, and bacon. Leafy greens such as spinach, kale and lettuce, along with broccoli, cauliflower and cucumbers, make healthy vegetable choices (but you’ll avoid starchy root foods like carrots, potatoes, turnips and parsnips). You can work in less-familiar veggies such as kohlrabi or daikon.
“If you’re going to do keto, there’s a better and a worse way to do it,” says Yawitz. “Loading your plate with meats, and especially processed meats, may increase your risk for kidney stones and gout,” which is a painful type of arthritis. “High intake of animal proteins makes your urine more acidic and increases calcium and uric acid levels. This combination makes you more susceptible to kidney stones, while high uric acid can increase your risk for gout,” adds Yawitz.
The ketogenic diet doesn’t put a cap on saturated fat or even trans fats. The latter are fats you should always avoid. Read ingredient labels and avoid any food with partially hydrogenated oils, aka trans fats. These fats heighten your LDL (“bad”) cholesterol levels and lower your HDL (“good”) cholesterol levels. They also raise your risk of heart disease and stroke, according to the American Heart Association.
The difference between ketosis and ketoacidosis is the level of ketones in the blood. Ketosis is a physiological adaptation to a low carbohydrate environment like fasting or a ketogenic diet. There are situations (such as treatment-resistant epilepsy) where ketosis can be beneficial to health. Ketoacidosis is an acute life-threatening state requiring prompt medical intervention; its most common form is diabetic ketoacidosis where both glucose and ketone levels are significantly elevated.
“Certainly, the quality of fat counts,” says Yawitz. “There’s a big difference nutritionally between bacon and almonds. As much as possible, people set on the keto diet should emphasize plant-based, unsaturated fats like nuts, seeds, olive oil, and avocado, which have even been shown to protect the heart.” If you have high cholesterol or other risk factors for heart disease, you should speak with your doctor before beginning the keto diet. This is because the diet may — but doesn't have to — include large amounts of saturated fat. Some studies have shown increases in cholesterol and triglycerides in people following the diet, while other research reveals that the keto diet may actually decrease heart disease risk as well as saturated fat intake.
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