Years ago I followed Paavo Airola's fasting program, and I still think he's one of the best on this subject. I fasted (fresh fruit and vegetable juices diluted with water) for ten days and that is the absolute best I have ever felt in my life. I'd bounce out of bed every morning, raring to go and with a lot of energy. However, I had been studying the method for a long time and my head was in the right place, plus I was very positive and kept things to myself because who needs negative feedback when you're trying to do something good for yourself? Part of it, however, included daily enemas because with only juices going through one's system, peristalsis is a factor and you want to clean out, not keep the toxins in. So, anyway, that's my experience, and I felt fantastic and have never felt that good since then. It was truly cathartic and healthy! Fasting is a breeze after the third day — no more hunger, but it is extremely necessary to know how to break the fast! That's probably the most important factor. He describes it all in his book, Are You Confused?. Lots of luck to you!