ketogenic

Ketogenic describes processes or diets that promote ketosis, a metabolic state in which ketone bodies become a primary energy source when carbohydrate intake is very low. Ketosis can occur during prolonged fasting, carbohydrate restriction, or when exogenous ketones are consumed.

The ketogenic diet is a high-fat, very low-carbohydrate diet designed to induce and maintain ketosis. Typical macronutrient distribution is about 70–75% fat, 20–25% protein, and 5–10% carbohydrates, with emphasis on nutrient-dense, fiber-rich foods. Variants include the standard ketogenic diet, high-protein ketogenic diet, targeted ketogenic diet (carbohydrates around workouts), and cyclical ketogenic diet (periodic higher-carb days). The diet often excludes most grains, sugars, and high-starch foods, while emphasizing meats, fish, eggs, full-fat dairy, non-starchy vegetables, nuts, seeds, and healthy fats.

Historically, the ketogenic diet was developed in the 1920s as a treatment for epilepsy, particularly drug-resistant pediatric epilepsy. It remains an accepted therapy for certain epilepsy cases and has been explored for other neurological conditions. Beyond epilepsy, ketogenic approaches have been studied for weight loss, type 2 diabetes, metabolic syndrome, and some neurodegenerative diseases, though evidence varies and long-term effects are still being investigated.

Mechanistically, carbohydrate restriction lowers insulin and glucose availability, increasing lipolysis. The liver converts fatty acids into ketone bodies—acetoacetate, beta-hydroxybutyrate, and acetone—that can supply energy to the brain and other tissues. Benefits reported in some studies include weight loss and improved glycemic control, but results are inconsistent across individuals.

Safety and monitoring are important. Early side effects, sometimes called the “keto flu,” can occur with rapid changes. Possible nutrient deficiencies, dehydration, kidney stone risk, and lipid profile changes may arise, especially with prolonged use. Medical supervision is advised for certain conditions, including pregnancy, liver or pancreatic disease, kidney problems, or eating disorders.