Found this online, don’t remember the source.
Stage 1 (Days 1-2)
On the first day blood sugar level drops below 70 mg/dl. To restore the blood to the normal glucose level, liver glycogen is converted to glucose and released into the blood. This reserve is enough for half a day. The body then reduces the basal metabolic rate (BMR). The rate of internal chemical activity in resting tissue is lowered to conserve energy. The heart slows and blood pressure is reduced. Glycogen is pulled from the muscle causing some weakness. The first wave of cleansing is usually the worst.
Headaches, dizziness, nausea, bad breath, glazed eyes and a heavily coated tongue are signs of the first stage of cleansing. Hunger can be the most intense in this period unless the enema is used which quickly assists the body into the fasting state by ending digestion in the colon.
Stage 2 (Days 3-7)
Fats composed of transformed fatty acids are broken down and converted to glucose. The skin may become oily as rancid oils are purged from the body. People with problem-free skin may have a few days of pimples or even boils. A pallid complexion is also a sign of waste in the blood. Ketones are formed by the incomplete oxidation of fats. It is suspected that the ketones in the blood suppress the appetite by affecting the food-satiety center in the hypothalamus. You may feel hungry for the first few days of the fast. This effect is temporary. The desire to eat will disappear. Lack of hunger may last 40 to 60 days, depending on whether you are on water or juice.
The body embraces the fast and the digestive system is able to take a much-needed rest, focusing all of its energies on cleansing and healing. White blood cell and immune system activity increases. You may feel pain in your lungs. The cleansing organs and the lungs are in the process of being repaired. Periodically, the lymphatic system expels mucoid matter through the nose or throat. The volume excreted of this yellow-colored mucus can be shocking. The sinuses go through periods of being clogged, then will totally clear. The breath is still foul and the tongue coated. Within the intestine, the colon is being repaired and impacted feces on the intestinal wall start to loosen.
Stage 3 (Days 8-15)
On the latter part of an extended fast, you can experience enhanced energy, clear-mindedness and feel better than you have felt since childhood. On the downside, old injuries may become irritated and painful. This is a result of the body’s increased ability to heal during fasting. If you had broken your arm 10 years before, there is scar tissue around the break. At the time of the break, the body’s ability to heal was directly related to lifestyle. If you lived on a junk-food diet, the body’s natural healing ability was compromised.
During fasting, the body’s healing process is at optimum efficiency. As the body scours for dead or damaged tissue, the lymphocytes enter the older, damaged tissue secreting substances to dissolve the damaged cells. These substances irritate the nerves in the surrounding region and cause a reoccurrence of aches from previously injured areas that may have disappeared years earlier. The pain is good as the body is completing the healing process. The muscles may become tight and sore due to toxin irritation. The legs can be the worst affected, as toxins accumulate in the legs. Cankers are common in this stage due to the excessive bacteria in the mouth. Daily gargling with salt and water will prevent or heal cankers.
Stage 4 (Days 16-30)
The body is completely adapted to the fasting process. There is more energy and clarity of mind. Cleansing periods can be short with many days of feeling good in between. There are days when the tongue is pink and the breath is fresh. The healing work of the organs is being completed. After the detoxification mechanisms have removed the causative agent or render it harmless, the body works at maximum capacity in tissue proliferation to replace damaged tissue. While a short fast will reduce the symptoms, a longer fast can completely heal. Homeostatic balance is at optimum levels. The lymphatic system is clean except for a rare discharge of mucus through the nose or throat. After day 20, the mind is affected. Heightened clarity and emotional balance are felt at this time. Memory and concentration improve.
Stage 5 (Breaking the Fast)
The sticky, toxic, mucoid coating on the intestinal wall is loose, and the first meal frees it from the intestinal wall. Toxins enter the blood through the colon. The gallbladder dumps its waste in a heavy discharge of bile. This can cause an instant bowel movement upon eating followed by intense diarrhea. If the symptoms are too uncomfortable, an enema will help.