The brain is composed of a network of neurons that transmit signals by propagating nerve impulses. The propagation of this impulse from one neuron to another is typically controlled by neurotransmitters, though there are also electrical pathways between some neurons. Neurotransmitters can inhibit impulse firing (primarily done by γ-aminobutyric acid, or GABA) or they can excite the neuron into firing (primarily done by glutamate). A neuron that releases inhibitory neurotransmitters from its terminals is called an inhibitory neuron, while one that releases excitatory neurotransmitters is an excitatory neuron. When the normal balance between inhibition and excitation is significantly disrupted in all or part of the brain, a seizure can occur. The GABA system is an important target for anticonvulsant drugs, since seizures may be discouraged by increasing GABA synthesis, decreasing its breakdown, or enhancing its effect on neurons.[7]
There are so many tricks, shortcuts, and gimmicks out there on achieving optimal ketosis – I’d suggest you don’t bother with any of that. Optimal ketosis can be accomplished through dietary nutrition alone (aka just eating food). You shouldn’t need a magic pill to do it. Just stay strict, remain vigilant, and be focused on recording what you eat (to make sure your carb and protein intake are correct).
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.
The DNA test does not necessarily take into account your goals (e.g. breathholding, Ironman, cognition, etc.) and if your goals would benefit from ketosis, then you may want to choose it as a dietary strategy even though it could indeed be true that for FAT LOSS a higher carb intake may suit you. So it all depends on your goals. Or you could just us the supplements like ketones AND eat more carbs and get "best of both worlds".
A lot of changes are happening in your body and you’re going to feel it! The first five to seven days can be pretty rough, but your body is getting over its dependency on sugar. During this time of transition it is essential that you supplement electrolytes. Your body is flushing out lots of water, and with that goes electrolytes. The Keto Flu can be greatly reduced if you add sodium, potassium and magnesium to your diet. Check out our supplements page for a list of electrolyte supplements we recommend. Stay on course and you’ll start feeling better in no time!
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.

There are numerous benefits that come with being on keto: from weight loss and increased energy levels to therapeutic medical applications. Most anyone can safely benefit from eating a low-carb, high-fat diet. Below, you’ll find a short list of the benefits you can receive from a ketogenic diet. For a more comprehensive list, you can also read our in-depth article here >


Our bodies are incredibly adaptive to what you put into it – when you overload it with fats and take away carbohydrates, it will begin to burn ketones as the primary energy source. Optimal ketone levels offer many health, weight loss, physical and mental performance benefits.1There are scientifically-backed studies that show the advantage of a low-carb, ketogenic diet over a low-fat diet. One meta-analysis of low-carbohydrate diets showed a large advantage in weight loss. The New England Journal of Medicine study resulted in almost double the weight loss in a long-term study on ketone inducing diets.
The Gatorade Sports Science Institute (GSSI) is widely considered one of the world’s top go-to resources for cutting-edge exercise and nutrition science advice – which is probably why Gatorade vending machines dot the campus here, and the majority of the kids seem to be walking around campus with a never-ending big gulp-sized cup full of sports drink.
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.
Me, I was a lot of things before I was keto: vegan, high starch, skinny, an Adderall abuser, paleo, Catholic, raw till 4, pescatarian, etc. The reason I went high fat/low carb was because some very smart-sounding people on the internet told me that I could “hack my body” and eat some fun things (bacon) if only I’d cut out a food group that was probably giving me constipation and cancer anyway.
The DNA test does not necessarily take into account your goals (e.g. breathholding, Ironman, cognition, etc.) and if your goals would benefit from ketosis, then you may want to choose it as a dietary strategy even though it could indeed be true that for FAT LOSS a higher carb intake may suit you. So it all depends on your goals. Or you could just us the supplements like ketones AND eat more carbs and get "best of both worlds".
I've tried that before(enzymedica digest gold for example) but it didn't seem to help much. It seems from testing that I have some heavy metal stuff going on and there might have been a chronic mold exposure in the past that is still reeking havoc and I imagine that might be affecting this pretty heavily. I will definitely be sticking to the avocadoes and coconut and 100% dark chocolate because I can't tolerate dairy. The hard part is figuring out what is the bare minimum of starch to make my gut feel good and be regular and at the same time become fat adapted and get those increased cognition and longevity benefits!!
Sleep enough – for most people at least seven hours per night on average – and keep stress under control. Sleep deprivation and stress hormones raise blood sugar levels, slowing ketosis and weight loss a bit. Plus they might make it harder to stick to a keto diet, and resist temptations. So while handling sleep and stress will not get you into ketosis on it’s own, it’s still worth thinking about.
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?
Those new to keto should be testing to see if their bodies are in ketosis, regardless of method. Testing, in general, is the most objective way to know if you’re in ketosis. There can be some subjective benefits of ketosis: appetite suppression, fat loss, low blood sugar, improvement in mental cognition and focus. But before recognizing these subjective benefits, it’s important to track and measure the level of ketones in the blood to ensure ketosis on a physical level.
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.
Great article! As someone who just started a “ketogenic diet” two weeks ago, I am opting to hold off on using ketone supplements for the following reason. You state how “Keto-adaptation occurs when you have shifted your metabolism to relying on fat-based sources, instead of glucose (sugar) sources, as your primary source of fuel.” If the goal is to “switch” our body’s energy supply to ketones and one uses supplemental ketones, how do they really ever know if their body has successfully accomplished this goal if they are using supplemental ketones? Aren’t they getting a false sense of ketosis if their blood or breath tests show them above 0.5 millimolar through the use of the supplements? I understand that it may take me longer to reach ketosis naturally but I guess I see it was worth it to truly reap all of the benefits that you outline in your article.
^ Lawrie 2014, pp. 92-. "A much delayed onset of rigor mortis has been observed in the muscle of the whale (Marsh, 1952b). The ATP level and the pH may remain at their high in vivo values for as much as 24h at 37ºC. No adequate explanation of this phenomenon has yet been given; but the low basal metabolic rate of whale muscle (Benedict, 1958), in combination with the high content of oxymyoglobin in vivo (cf 4.3.1), may permit aerobic metabolism to continue slowly for some time after the death of the animal, whereby ATP levels can be maintained sufficiently to delay the union of actin and myosin in rigor mortis."

Ben. I do not read epidemiological studies anymore… Just biology. There are plenty of examples of traditional cultures consuming high carb (and high fat) without any of the health issues those studies in your article claim. So either high fat or high carb both work if done properly… AND in the right environment. Both are ancestral not just one of the two and have posit and negat because it has to do with the climate and environment around. I do not listen to anybody that pushes JUST one because they are ignoring the reality. I hope you join this "common sense" wagon.
Physicians of ancient Greece treated diseases, including epilepsy, by altering their patients' diet. An early treatise in the Hippocratic Corpus, On the Sacred Disease, covers the disease; it dates from c. 400 BC. Its author argued against the prevailing view that epilepsy was supernatural in origin and cure, and proposed that dietary therapy had a rational and physical basis.[Note 3] In the same collection, the author of Epidemics describes the case of a man whose epilepsy is cured as quickly as it had appeared, through complete abstinence of food and drink.[Note 4] The royal physician Erasistratus declared, "One inclining to epilepsy should be made to fast without mercy and be put on short rations."[Note 5] Galen believed an "attenuating diet"[Note 6] might afford a cure in mild cases and be helpful in others.[11]
You need to do a “common man’s” version of a good ketogenic nutrition program or discussion. Great article, and I leaned a few things. Those Ketone Salts and other supplements can get pricey. I eat a very low carb and high fat diet and meander in and out of ketosis during the week. A pure ketogenic diet is so restrictive that meals it can get very repetitive during the week. I’d like to learn more about cooking with oils and how temperature effects their qualities. I can only handle eating so much raw food, and I love to cook my greens and other vegetables in bacon fat and coconut oil. It will be next May before I can get my blood work performed (insurance reasons) so until then I’ll need to be careful and hold back on those after supper dark chocolate excursions! Thanks!!

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.
Although you'll be cutting way back on carbohydrates and sugar, some fruits are still okay to eat on the keto diet (though you'll still want to be mindful about quantity in order to remain in ketosis). The fruits that make the cut contain far fewer carbs than their off-limits cousins such as apples, pears, bananas, pineapples, papayas, grapes, and fruit juices in general.

Carbohydrates help control blood sugar levels, which are of particular importance for people with diabetes. A study published in May 2018 in the journal Diabetic Medicine shows that while a keto diet may help control HbA1c levels (a two- to three-month average of blood sugar levels), the diet may also cause episodes of hypoglycemia, which is a dangerous drop in blood sugar. Echoing many registered dietitians, the Lincoln, Nebraska–based sports dietitian Angie Asche, RD, says she is “hesitant to recommend a ketogenic diet for individuals with type 1 diabetes.”


Western diets are high in carbohydrates, leading to high blood sugar levels, whereas the ketogenic diet enforces a small amount of carbs to be consumed. It can take some weeks of keto dieting to reach increased levels of blood ketones. For others, after 2 - 4 days of low-carbohydrate, high-fat ketogenic dieting, ketone levels in the blood can increase to ~1 - 2 mM, achieving ketosis.5
People seem to expect, based on fitness guru promises, that being in a state of ketosis feels like a cognition-enhancing, energy-stimulating power hour whereby your waist measurement is negatively correlated with your IQ. I usually just felt fatigued as hell if I tried to exercise, beating my body to death on an aged and grating stair climber at 6am. Then I went about the day eating random assortments of protein and fat, felt totally out of control at the sight of brownies in the office, overdid coffee to suppress my cravings and increase my metabolism, and went to bed feeling the dull ache of deprivation underneath my dieting high. And that was only the beginning.

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.
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!
Typically, to gain lean body mass one needs to have some degree of caloric surplus, or at the very least, not be in a significant deficit. This is especially true when looking to add muscle mass. It is certainly possible to gain muscle mass on a ketogenic diet. For most individuals this would require consuming adequate protein (while still remaining in ketosis), enough calories to support growth, sufficient electrolytes to support muscle function, as well as incorporating progressive resistance training. The type and volume of resistance exercise needed to add lean body mass will be very dependent on the individual and their age, training status, health status, etc. Therefore, the answer to this question can become quite nuanced, but in simple terms, yes, it is very possible to gain lean body mass on a ketogenic diet while still taking advantage of the health promoting effects this way of eating provides.
Now I though about taking keto supplement to boost my ketosis (I’m also looking to boost my overall electrolyte and vitamin/mineral). I’m unsure what product to take. Should I take keto os or ketocana (or else)? Should I take it in the morning while I’m empty stomack for the next 6 hours (wake up at 5) with my mg cap so I get a boost in electrolyte and keto in the morning? Should I take more? Depending on the set, I might not have to take mg cap anymore since they all include some in it.

Can’t get enough of avocados? You now have a great excuse to eat more of them. A ½-cup serving of the creamy fruit has almost 12 g of fat and only 2.6 g of net carbs. Avocados are also low in calories (about 138 for the same serving), making them an ideal snack in between meals. One serving also has about 6.4 g of dietary fiber (25.6 percent daily value, or DV), 404 milligrams (mg) of potassium (8.6 percent DV), and only 2.8 g of sugar. Try topping your salad with cubed avocado for a keto-friendly lunch.
Bulk buy and cook. If you’re someone who doesn’t like to spend a lot of time in the kitchen, this is the best of both worlds. Buying your food at bulk (specifically from wholesalers) can reduce the cost per pound tremendously. Plus, you can make ahead food (bulk cook chicken thighs for pre-made meat, or cook entire meals) that are used as leftovers, so you spend less time cooking.

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.
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. 
Apparently, Dominic’s research seems to be suggesting the fact that diet-induced ketosis from a high-fat, low-carb intake, especially when combined with the use of nutrition supplements such as powdered ketones or MCT oil, can vastly reduce the need for the brain to use oxygen to burn glucose. This is because the brain can use up to around 75% of its fuel from ketones. So a ketone-fed or a fat-adapted brain can be better equipped to withstand low oxygen availability and potentially support longer breath-hold times. Dominic’s research also shows that in the presence of ketosis, the brain and body are able to resist the potential cell damage of long periods of time with low oxygen, also known as “hypoperfusion”.
I was shocked at how easy it was (using the new supplements and methods outlined below that have been developed since my initial foray into ketosis) to get into ketosis without extreme carbohydrate restriction, without excessive, diarrhea and “diaper-moment” inducing amounts of MCT and coconut oil, and without the inflammation, triglyceride and hormonal issues, or social discomfort I outline above. I was also able to achieve a much more immediate and deeper level of ketosis than I ever achieved in previous experiments sans these newer strategies you’re going to learn about.
Considered a symptom of the keto flu, your breath on this diet often smells fruity at first. This is because acetone is a by-product of ketosis and is eliminated mostly through the lungs and the breath, according to a study in the journal International Journal of Environmental Research and Public Health in February 2014. Acetone is a type of ketone known for having a fruity aroma in smaller concentrations. “It’s hard to say exactly how long it will last as it depends on the person, but it’s common for someone to experience this side effect for a few weeks,” says Asche.
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.
Ketones are a special type of fat that can stimulate the pathways that enhance the growth of new neural networks in the brain. A ketogenic diet is one that is high in fats, and this diet has been a tool of researchers for years, used notably in a 2005 study on Parkinson’s patients finding an improvement in symptoms after just 28 days. The improvements were on par with those made possible via medication and brain surgery. Other research has shown the ketogenic diet to be remarkably effective in treating some forms of epilepsy, and even brain tumors.

^ Lawrie 2014, pp. 92-. "A much delayed onset of rigor mortis has been observed in the muscle of the whale (Marsh, 1952b). The ATP level and the pH may remain at their high in vivo values for as much as 24h at 37ºC. No adequate explanation of this phenomenon has yet been given; but the low basal metabolic rate of whale muscle (Benedict, 1958), in combination with the high content of oxymyoglobin in vivo (cf 4.3.1), may permit aerobic metabolism to continue slowly for some time after the death of the animal, whereby ATP levels can be maintained sufficiently to delay the union of actin and myosin in rigor mortis."
Moreover, recent studies show that the Inuit have evolved a number of rare genetic adaptations that make them especially well suited to eat large amounts of omega-3 fat.[57][58][59] And earlier studies showed that the Inuit have a very high frequency—68% to 81% in certain arctic coastal populations—of an extremely rare autosomal recessive mutation of the CPT1A gene—a key regulator of mitochondrial long-chain fatty-acid oxidation[60][61]—which results in a rare metabolic disorder known as carnitine palmitoyltransferase 1A (CPT1A) deficiency and promotes hypoketotic hypoglycemia—low levels of ketones and low blood sugar.[62] The condition presents symptoms of a fatty acid and ketogenesis disorder.[62] However, it appears highly beneficial to the Inuit[60] as it shunts free fatty acids away from liver cells to brown fat, for thermogenesis.[63][64] Thus the mutation may help the Inuit stay warm by preferentially burning fatty acids for heat in brown fat cells.[64] In addition to promoting low ketone levels, this disorder also typically results in hepatic encephalopathy (altered mental state due to improper liver function), enlarged liver and high infant mortality.[65] Inuit have been observed to have enlarged livers with an increased capacity for gluconeogenesis, and have greater capacity for excreting urea to remove ammonia, a toxic byproduct of protein breakdown.[57][66][67][68] Ethnographic texts have documented the Inuit's customary habit of snacking frequently [69] and this may well be a direct consequence of their high prevalence of the CPT1A mutation[70] as fasting, even for several hours, can be deleterious for individuals with that allele, particularly during strenuous exercise.[57][70] The high frequency of the CPT1A mutation in the Inuit therefore suggests that it is an important adaptation to their low carbohydrate diet and their extreme environment.[57][60][70]

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.
Drink lots of water. This is especially crucial on a low carb or keto diet. Why? When you eat carbohydrates, your body stores the extra as glycogen in the liver, where they are bound to water molecules. Eating low carb depletes this glycogen, which allows you to burn fat – but it also means you are storing less water, making it easier to get dehydrated. Instead of the traditional recommendation of 8 cups of water per day, aim for 16 cups when following a low carb lifestyle.
I'd recommend starting with glucose and hemoglobin A1C, along with a good multi like https://bengreenfieldfitness.com/multi and a fish oil like the one at greenfieldfitnesssystems.com – Anyways, 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.
Here’s what we do know: The keto diet may be useful in treating symptoms of epilepsy, a seizure disorder. “The use of keto in treating epilepsy has the most evidence,” Angelone says. One study conducted by Johns Hopkins Medicine, for example, followed epileptic patients on the keto diet and found that 36 percent of them had a 50 percent reduction in seizures after three months on the diet, and 16 percent were seizure-free. However, experts aren't entirely sure why the keto diet has this affect, she adds.
In one week my husband lost 1.5 kg because of Keto diet and recipes. Thank you for the insights and tips. I would like to have a complete recipe for meals everyday and hoping by subscribing I will receive try my mail. I will keep u posted. It takes 2 to tango. The one who wants to diet must be cooperative with the plan and execution while the other person who is preparing the food must be patient to the dieting person. Its not easy to change meals so patience is required
Elevated blood ketone levels is the sign of ketosis, while certain subjective symptoms can also signal ketosis. Increased mental clarity, less brain fog, and diminished appetite are fairly common among people in ketosis. The ketogenic diet specifically has its own assortment of symptoms. Fortunately, the negative symptoms such as constipation, diarrhea, and bad breath are often temporary and tend fade as your body becomes better at fat burning and naturally producing ketones. The positive symptoms of ketosis coincide with higher levels of ketones in the blood. This may occur after several weeks of adhering to the ketogenic diet or very shortly after ingesting exogenous ketones.
Awesome info. I’ve been LCHF moderate protein (about 1 g per lean lbs/mass) and 50-100g of carbs for about a year. I’d consume around 2500 cals. I’m active 4-5 days a week (60-90 min cycling sessions) I started using MCT/Butter coffee. It surpressd my appetite and I would only eat whole food at lunch/dinner…still LCHF, but since my appetite was lower I was only takin in about 1800 cals. After about 2 weeks I started to gain body fat. Do you think the reduced caloric intake is the culprit? Should I “force” myself to eat…maybe up the MCT intake to make up the difference?
On the keto diet, your body begins to shed fat, water and glycogen, and as this happens you lose key electrolytes, such as sodium, potassium and magnesium. When you're running low on these electrolytes, you might experience headaches or extreme fatigue. These losses are most pronounced during the first few weeks after you enter ketosis, so if you're going to start the keto diet it's best to plan ahead to make sure you get healthy amounts of these electrolytes — and other vitamins and minerals — either through supplements or a thoughtfully-designed meal plan.

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.
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