you have a good point. who knows better than the person that is fasting how they feel? if we respect ourselves, we will pay attention to our body's signals. that is what i am doing too. i feel that if things get too much for me, i just drink some home made juice. we our our own experts in some cases. i couldn't afford to go to a fasting retreat right now. too expensive. and i think it would also irritate me that someone was telling me what to do and monitoring me. but i liked what he said anyhow because i could tell it was out of sincere concern especially for those who never fasted before.. either juice, water or anything.