Fast Fit Keto : However, many find the keto diet difficult and take weeks to get into the rhythm. With Fast Fit Keto, you can naturally achieve the state because it kicks the metabolic ketosis state into action for a positive result.One reason many fail to get the result through diet is their food, which carries carbohydrates. Carbs are a fast source of energy and are not the primary source of energy. When our body burns these carbs for energy instead of stored fat, we feel stressed and drained after a long workday.