Whether it's from work, a family emergency, vacation, or partying too much, we know when we reach this point, and know we will have to get down into shape. A true Keto diet requires you to try without any carbohydrates for 5 or 6 days soon after which it allows a 1 or 2 day "carb-up". Well really, the goal of cutting is exactly what it says, and that is, decrease back on some of that fat.