Low-carbohydrate diets or low-carb diets are dietary programs that restrict carbohydrate consumption usually for weight control or for the treatment of obesity. Foods high in digestible carbohydrates (e.g. bread, pasta) are limited or replaced with foods containing a higher percentage of proteins and fats (e.g. meat, poultry, fish, shellfish, eggs, cheese, nuts, seeds and peanuts) and other foods low in carbohydrates (e.g. most salad vegetables), although other vegetables and fruits (especially berries) are often allowed. The amount of carbohydrate allowed varies with different low-carbohydrate diets.
Such diets are sometimes ketogenic (i.e. they restrict carbohydrate intake sufficiently to cause ketosis), such as the Induction phase of the Atkins diet. Some sources, though, consider less restrictive variants to be low-carbohydrate as well.
In addition to obesity, low-carbohydrate diets are used as treatments for some other conditions, notably diabetes,epilepsy,chronic fatigue syndrome (see ketosis) and polycystic ovarian syndrome.