Image result of keto flex FAQ Bredesen Protocol(tm) diet is Nutritional Ketosis as well as Time-Restricted Eating of nutritious, nutrient-rich food items. KetoFlex 12/3 is eating all meals during a 12-hour time frame and making sure you do not eat anything within three hours before going to sleep. For instance, if you fall asleep at 10 p.m., be sure to finish eating by 7 PM.