Carbohydrate-restricted ketosis: This type of ketosis mimics the same biological alterations seen during lengthy fasts, but without the complete restriction of food. Carbohydrate-restricted ketosis is achieved primarily through a very low-carbohydrate ketogenic diet. This restriction, in turn, results in reductions of insulin and blood glucose levels similar to that of fasting, which again increases blood ketone levels. For most individuals, nutritional ketosis is much more sustainable than fasting or starvation ketosis. Fasting can still have its place in a keto diet for beginners. Many individuals following a ketogenic diet like to implement a regular fasting protocol such as intermittent fasting (IF) (12–20 hours daily) or every-other-day fasts (EOD), depending on their goals. This practice is not critical for success on a ketogenic diet, but it can enhance the level of ketone production, and thus magnify the benefits.

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]
Now that ketogenic diets have become popular, many keto hybrid diets have sprung up, including plant-based versions. (One is “ketotarian,” which is predominantly plant-based but includes the option of eggs, ghee, and fish and shellfish.) While this approach can be healthy, Hultin cautions against trying keto as a vegan. “Because you can’t eat beans or lentils on a ketogenic diet, and nuts and seeds are even limited due to their carbohydrate content, you’re really just left with some tofu and will need to rely on low-carb protein powder,” she says. There is a good possibility this won’t pan out. “I don’t see this as a sustainable diet due to the extreme restrictions,” she says.
A simple standby, but one that ketoers adore. 2 or 3 fried eggs and some bacon might not sound like much, but it’s full of protein that will keep you full and energized all morning. Take the opportunity on the weekend to lay your bacon strips on a single cookie sheet and bake in the oven for 20 minutes at 400 degrees. The result is the best bacon you’ve ever had, in a big batch, with no sitting over a popping, hissing frying pan.
After initiation, the child regularly visits the hospital outpatient clinic where they are seen by the dietitian and neurologist, and various tests and examinations are performed. These are held every three months for the first year and then every six months thereafter. Infants under one year old are seen more frequently, with the initial visit held after just two to four weeks.[9] A period of minor adjustments is necessary to ensure consistent ketosis is maintained and to better adapt the meal plans to the patient. This fine-tuning is typically done over the telephone with the hospital dietitian[19] and includes changing the number of calories, altering the ketogenic ratio, or adding some MCT or coconut oils to a classic diet.[18] Urinary ketone levels are checked daily to detect whether ketosis has been achieved and to confirm that the patient is following the diet, though the level of ketones does not correlate with an anticonvulsant effect.[19] This is performed using ketone test strips containing nitroprusside, which change colour from buff-pink to maroon in the presence of acetoacetate (one of the three ketone bodies).[45]
A ketogenic diet (also known as the keto diet) is typically lower in carbohydrates and higher in fats than a standard American diet. Once your body adapts to a ketogenic diet, it switches from primarily using carbohydrates and glucose to fat and ketones as fuel. This adaptation within the body increases fat breakdown and oxidation, which can improve body composition, general health, performance, and perhaps even longevity! The amount of fat, carbohydrates, and protein needed to achieve a well-formulated keto diet for beginners differs from person to person and is goal-dependent. Any dietary protocol in which you are lowering carbohydrates sufficiently enough to induce a state of ketosis can be considered a ketogenic diet. However, throughout this guide you will begin to understand how to construct a well-formulated ketogenic diet to meet your goals.
Achieving optimal ketosis hinges on finding the right balance of macronutrients (or “macros” in keto-speak); these are the elements in your diet that account for the majority of your calories, a.k.a. energy—namely, fat, protein, and carbohydrates. By the way, it’s often “net grams” of carbohydrates that are counted toward your daily intake; “net” deducts the amount of fiber in a food from its carbohydrate total.