Answer: The only weight loss benefit resulting from a colon cleanse is the weight removed from your intestines. In other words, the number on the scale may go down immediately after you cleanse, but unless you are “dieting” that number will return to normal soon after. You only lose body weight (fat or lean tissue) when you consume fewer calories than you burn or through a surgical procedure that removes some part of the body.
Additionally, there are no validated health benefits from colon cleansing. We do not recommended colon cleansing, or fasting for that matter.
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There is a very weak theory of "autointoxication" claiming that stagnation of the large intestine (colon) causes toxins to form. The theory suggests that these unknown toxins are then absorbed by the body and begin to poison it. Some proponents depict the large intestine as a “sewage pipe and tank” that becomes a "cesspool" if neglected. However, the vast majority of the digestive process takes place in the small intestine, from which nutrients are absorbed into the body. The remaining mixture of food and undigested particles then enters the large intestine, which can be compared to a 40-inch long hollow tube. Its principal functions are to transport food wastes and bacteria from the small intestine to the rectum for elimination and to absorb some minerals, electrolytes and water to maintain the body’s fluid and electrolyte balance.
The colon is very efficient at keeping itself clean, and there is no published research on colon cleansing for better health or to prevent disease.
The only reason to cleanse the colon is in preparation for a medical examination of the colon. Colonic cleanses are not only expensive but potentially harmful. Some colon-cleansing programs disrupt the water and electrolyte balance and can be harmful by causing dehydration and salt depletion.
Equipment that is not sterilized can transmit diseases from one person to the next causing serious infections. In some cases the bowels can be punctured from inserting the tube and cause life-threatening diseases or death. Legal action has been taken by local and federal government authorities against healthcare professionals who have performed colonic irrigations. The FDA classifies colonic irrigation systems as Class III devices that cannot be marketed except for medically indicated colon cleansing for radiographic endoscopy.
Based on current data, we discourage the use of colonics and detoxification systems due to safety concerns. They should only be used by trained, medical professionals for the purpose of medical examinations of the colon. For those truly interested in ridding the body of man-made poisons, the best current method is to avoid contact in the first place.