As you may know, "keto diet" is short for ketogenic diet, because who has the time to say "genic." It is a high-fat, moderate-protein, and low-carb diet with approximately 80% of your calories from fat, 15% from protein, and only 5% from carbohydrates. The goal of the diet is to induce ketosis in your body. The theory is that typically your body may rely on burning the carbs that you eat rather than the fat stores in your body for energy. The thinking is that by severely restricting the amount of carbs in your diet your body may then be forced to burn your body fat instead. Breaking down this fat then results in ketones, which is not some acapella group, but instead organic compounds made up of carbon, hydrogen, and oxygen atoms. One type of ketone produced is acetone, which is in certain types of nail polish removers. This accumulation of ketones may result in "keto breath", which is a rotten fruit or metallic smelling bad breath that can smell a bit like, surprise, surprise, nail polish remover.

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]


If you’ve decided keto is a good fit for your wellness goals, and you want to add fruit to your meal plan, choose fruits with the least amount of net carbs, which is the total amount of carbohydrate content in a fruit minus its fiber content (since the body can’t digest fiber), according to the website for the popular low-carb diet Atkins. The keto diet allows for about 25 g of net carbs per day, per the healthy-lifestyle website Ruled.me. Dietitians recommend reaching for the following.

So if your high-fat diet includes a high amount of roasted seeds or roasted nuts, nut butters, heated oils such as heated coconut oil or heated extra virgin olive oil, barbecued meats or meats cooked at very high temperatures, then your triglyceride count is going to go up. You should have triglycerides that are less than 150mg/dL, and a triglyceride to HDL ratio that is no more than 4:1, and in most of the healthiest people I’ve worked with, triglycerides are under 100 and the triglyceride to HDL ratio is less than 2:1. If your ratio is whacked, your ketotic diet isn’t doing you any favors.
Some clinicians[37] regard eliminating carbohydrates as unhealthy and dangerous.[38] However, it is not necessary to eliminate carbohydrates from the diet completely to achieve ketosis. Other clinicians regard ketosis as a safe biochemical process that occurs during the fat-burning state.[35] Ketosis, which is accompanied by gluconeogenesis (the creation of glucose de novo from pyruvate), is the specific state that concerns some clinicians. However, it is unlikely for a normally functioning person to reach life-threatening levels of ketosis, defined as serum beta-hydroxybutyrate (B-OHB) levels above 15 millimolar (mM) compared to ketogenic diets among non diabetics, which "rarely run serum B-OHB levels above 3 mM."[39] This is avoided with proper basal secretion of pancreatic insulin. People who are unable to secrete basal insulin, such as type 1 diabetics and long-term type II diabetics, are liable to enter an unsafe level of ketosis, eventually resulting in a coma that requires emergency medical treatment.[citation needed] The anti-ketosis conclusions have been challenged by a number of doctors and advocates of low-carbohydrate diets, who dispute assertions that the body has a preference for glucose and that there are dangers associated with ketosis.[40][41]

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]

To encourage ketone production, the amount of insulin in your bloodstream must be low. The lower your insulin, the higher your ketone production. And when you have a well-controlled, sufficiently large amount of ketones in your blood, it’s basically proof that your insulin is very low – and therefore, that you’re enjoying the maximum effect of your low-carbohydrate diet. That’s what’s called optimal ketosis.


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.

Food is your body’s primary source of energy, and three main nutrients in foods supply your body with this energy. These are carbohydrates, fat, and protein. Typically after eating a meal, your body will first break down carbohydrates from foods, and then fat and protein.Ketosis is a natural metabolic state that occurs when your body doesn’t have enoughcarbs (or glucose) for energy, so it burns fat instead.

Some research suggests that ketogenic diets might help lower your risk of heart disease. Other studies show specific very-low-carb diets help people with metabolic syndrome, insulin resistance, and type 2 diabetes. Researchers are also studying the effects of these diets on acne, cancer, polycystic ovary syndrome (PCOS), and nervous system diseases like Alzheimer's, Parkinson's, and Lou Gehrig's disease.


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.
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]
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?

“Rapid, significant weight loss is a common side effect of the keto diet because of the water losses that occur as carbohydrate stores are depleted,” says Clark. In a study in the American Journal of Clinical Nutrition, obese men following a modified version of the ketogenic diet, with high protein and low carbs, lost about 14 pounds in one month, compared with the control group, which lost about 10 pounds on a high-protein, medium-carb diet.
The Johns Hopkins Hospital protocol for initiating the ketogenic diet has been widely adopted.[43] It involves a consultation with the patient and their caregivers and, later, a short hospital admission.[19] Because of the risk of complications during ketogenic diet initiation, most centres begin the diet under close medical supervision in the hospital.[9]

Eat fewer calories by lowering your fat intake. On keto, protein and carb intake is usually the same for everyone, but you may want to adjust your fat intake to eat fewer calories than you're eating now. Because keto has a metabolic advantage over other weight-loss diets, you may only need to reduce your calories slightly (around 300 kcal less a day).

Hey Alex, thanks for commenting and great to have you as a new listener! For this kind of thing, because it requires so going into detail, I'd suggest you book a consult with me by going to
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]
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.
For example, in trained people and athletes who eat a low-carbohydrate, high-fat diet (not to be confused with a low-carbohydrate, high-protein diet), a large amount of fat burning can take place at intensities well above 80 percent maximum oxygen utilization (VO2 max) – allowing for very-high-intensity or long efforts with low calorie intake and also allowing for use of fat fuel stores during long steady-state exercise, even at a relatively fast pace (so much for the “fat burning zone” giving you the best bang for your buck). With high-fat, low-carb intake, you can go hard and still burn tons of fat. In addition, this means that more carbohydrate stores will be available when you really need them, such as for an all-out, 100%, maximum effort.
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]