I have to agree with Wheatgrass Yogi. It may sound strange,but the longer the fast the "purer" it needs to be. Water plus nothing fasts seem to have less muscle wasting than fasts that include supplements. When the body goes into starvation mode it continues to seek glucose for fuel including stored glucose in muscles and organs. This is why famine victums and anorexics look so terrible. Water plus nothing stays in ketosis as long as there is body fat to provide ketones. It also allows the body to break down tumors, abcesses and mineral deposits in joints. These stored minerals erode the joints and cause arthritis. That is why distilled water is best.