The second essential concern has to do with adjusting the intensity of the fast. Some individuals are so toxic that the waste products released during a fast are too strong, too concentrated or too poisonous for the organs of elimination to handle safely, or to be handled within the willingness of the faster to tolerate the discomforts that toxic releases generate. The highly-toxic faster may even experience life-threatening symptoms such as violent asthma attacks. This kind of faster has almost certainly been dangerously ill before the fast began. Others, though not dangerously sick prior to fasting, may be nearly as toxic and though not in danger of death, they may not be willing to tolerate the degree of discomfort fasting can trigger. For this reason I recommend that if at all possible, before undertaking a fast the person eat mostly raw foods for two months and clean up all addictions. This will give the body a chance to detoxify significantly before the water fast is started, and will make water fasting much more comfortable. Seriously, dangerously ill people should only fast with experienced guidance, so the rapidity of their detoxification process may be adjusted to a lower level if necessary. A fast of only one week can accomplish a significant amount of healing. Slight healing does occur on shorter fasts, but it is much more difficult to see or feel the results. Many people experience rapid relief from acute headache pain or digestive distress such as gas attacks, mild gallbladder pain, stomach aches, etc., after only one day's abstention from food. In one week of fasting a person can relieve more dangerous conditions such as arthritic pain, rheumatism, kidney pain, and many symptoms associated with allergic reactions. But even more fasting time is generally needed for the body to completely heal serious diseases. That's because eliminating life-threatening problems usually involve rebuilding organs that aren't functioning too well. Major rebuilding begins only after major detoxification has been accomplished, and this takes time. Yes, even lost organ function can be partially or completely restored by fasting. Aging and age-related degeneration is progressive, diminishing organ functioning. Organs that make digestive enzymes secrete less enzymes. The degenerated immune system loses the ability to mobilize as effectively when the body is attacked. Liver and kidney efficiency declines. The adrenals tire, becoming incapable of dumping massive amounts of stress-handling hormones or of repeating that effort time after time without considerable rest in between. The consequences of these inter-dependent deterioration's is a cascade of deterioration that contributes to even more rapid deterioration's. The name for this cascading process is aging. Its inevitable result--death. Fasting can, to a degree, reverse aging. Because fasting improves organ functioning, it can slow down aging.