My wife and I just completed the 21 day primal challenge. I will only speak for myself here. I feel great and have already seen some fair amount of weight loss. Muscle tone is geting very good and energy levels are up. I was quite the insomniac before averaging about 4-5 hrs a night. Now, I sleep a good 7-8 each night. Little aches and pains that were there constantly are now gone. I am staying primal!