Eventually waste turns the corner and enters the top portion, hardening into stool as it goes along. Finally, the finished product turns another corner and enters the descending portion of the colon, where it waits to be eliminated. The difference between an enema and a colonic is the distance that the water travels up the colon. With an enema, the water remains by the rectum and at most gets halfway up the descending colon. The aim of colonics is to force the water (either with pressurized water or gravity) through the entire length of the colon, all the way around to the ileocecal valve. Most colonic experts say that it takes more than one colonic to get all the way around to the other end of the colon. One colonic expert begins with a client lying on her left side so that the water collects in the descending colon. Then the client rolls onto her back so that the water moves into the next portion.
The 15-gallons (68 litres) of water typically used in a 30- to 45-minute session are not shot all at once. Some therapists ask clients to call out when they feel extremely full. Then the therapist will shut off the water and open the output valve. Water and debris - and indigestible foods - then flow out to the sewer (with the colonicist watching the clear tube and making comments on what's coming out, such as "You must remember to chew your food").
Other therapists say they can tell when the client is full. It's very intuitive work, says one. The process is one of water repeatedly flowing in and out. One of the big fears, usually put forth by gastroenterologists, is that too much water will be flushed into the colon, causing it to burst. A medical doctor, who has counseled some of his patients to get colonics, agrees that there is some risk to the procedure. According to him, the biggest danger is "operator failure". If the therapist turns on the machine for instance, and then leaves the room, you're going to be in big trouble.
But what exactly is the point of all this? Colonic pushers have developed their own rather medieval mythology as to how the digestive system works and how it becomes dysfunctional. Almost every colonic therapist believes that people have years worth of waste stored up in their colons. They say that this ancient matter is making people toxic and that unless they are having bowel movements three times a day they've probably fallen prey to the broken-down system. Practitioners also love to haul out diagrams of colons twisted up like a roller coaster from, they say, stress.