There are two essential rules of fasting. If these rules are ignored or broken, fasting itself can be life threatening. But if the rules are followed, fasting presents far less risk than any other important medical procedure with a far greater likelihood of a positive outcome. And let me stress here, there is no medical procedure without risk. Life itself is fraught with risk, it is a one-way ticket from birth to death, with no certainty as to when the end of the line will be reached. But in my opinion, when handling degenerative illness and infections, natural hygiene and fasting usually offer the best hope of healing with the least possible risk. The first vital concern is the duration of the fast. Two eliminatory processes go on simultaneously while fasting. One is the dissolving and elimination of the excess, toxic or dysfunctional deposits in the body, and second process, the gradual exhaustion of the body's stored nutritional reserves. The fasting body first consumes those parts of the body that are unhealthy; eventually these are all gone. Simultaneously the body uses up stored fat and other reserve nutritional elements. A well-fed reasonably healthy body usually has enough stored nutrition to fast for quite a bit longer than it takes to "clean house." While house cleaning is going on the body uses its reserves to rebuild organs and rejuvenate itself. Rebuilding starts out very slowly but the repairs increase at an ever-accelerating rate. The "overhaul" can last only until the body has no more reserves. Because several weeks of fasting must pass by before the "overhaul" gets going full speed, it is wise to continue fasting as long as possible so as to benefit from as much rejuvenation as possible. It is best not to end the fast before all toxic or dysfunctional deposits are eliminated, or before the infection is overcome, or before the cause for complaint has been healed. The fast must be ended when most of the body's essential-to-life stored nutritional reserves are exhausted. If the fast goes beyond this point, starvation begins. Then, fasting-induced organic damage can occur, and death can follow, usually several weeks later. Almost anyone not immediately close to death has enough stored nutrition to water fast for ten days to two weeks. Most reasonably healthy people have sufficient reserves to water fast for a month. Later I will explain how a faster can somewhat resupply their nutritional reserves while continuing to fast, and thus safely extend the fasting period.