From my research, the reason to fast after 3 or 4 is increadibly important. An empty stomach, no work (no food assimilation) for the liver and kidneys put you in the best position to detox. All of your organs have no other work then to clean cell by cell. I find dry fasting after 3 makes me sleepy by 7. I naturally go into the deepest sleep I've ever had in my life. I hope this helps, and I definately know you need to do what's right for you. (I just wish somebody could have told me what I know now, 10 years ago!) I am literally waking up looking younger after one of these 'dead to the world' sleeps!