Low-carb high fat diet (LCHF). The term keto originates from ketosis, which is a fat-burning metabolic state that occurs when you limit your carbohydrates intake. Without the carbs, your body burns through fat for energy instead of glucose. Ketones are the compounds that are produced, and their presence means your body is in ketosis, or a fat-burning state. Eats things like avocado, eggs, steak, keto bulletproof coffee with grass fed unsalted butter and organic coconut oil or MCT oil. Find here the best keto spots near you in Barcelona.