No-carbohydrate diet

A no-carbohydrate diet (no-carb diet, zero carb diet) excludes dietary consumption of all carbohydrates (including dietary fiber) and suggests fat as the main source of energy with sufficient protein. A no-carbohydrate diet may be ketogenic, which means it causes the body to go into a state of ketosis, converting dietary fat and body fat into ketone bodies which are used to fuel parts of the body that do not oxidize fat for energy, especially the brain. Some bodily organs and parts of the brain still require glucose, which is tightly regulated by the liver and adequately supplied by gluconeogenesis or by converting glycerol from the breakdown of triglycerides. A no-carbohydrate diet may use mainly animal source foods and may include a high saturated fat intake, though this is not prescriptive of the diet, which, by definition, only restricts carbohydrate intake.

One of the first registries on low-carbohydrate diets was in 1860 when English casket maker William Banting was prompted to lose weight and decided to write "Letter on Corpulence, Addressed to the Public", which aimed to completely avoid starch and sugar. Banting lost 45 pounds in a few weeks (with additional weight loss over several months) on a diet composed by meat (generally mutton or beef - plus poultry and fish), two very small (1 ounce) portions a day of rusk or dry toast, tea (with no sugar or milk), and a 2-4 drinks of dry wine or port a day as spelled out in his own writings (https://archive.org/details/letteroncorpulen00bant). Thus, the Banting diet became a very well known method during that period of the 19th century, promoted also for weight loss and diabetes control.

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