You would think people would be relieved to hear they didn’t have to pump liquid into their rectum in order to clear out clogged waste and “toxins.” But despite the lack of evidence to support colonics—a practice that also goes by the names colon hydrotherapy, colon irrigation and colon cleansing—most gut doctors are asked about the procedure on a weekly, if not a daily, basis.
“It’s a very popular subject for patients to bring up,” says Dr. Brooks Cash, a professor of medicine at the University of South Alabama. “A lot of people think it will help with weight loss, and I tell them there’s really no data in the medical literature to support any significant health benefits.”
Cash would know. He co-wrote a review article on colon cleansing while working in the department of gastroenterology at the National Naval Medical Center. “We didn’t find any benefit, but we did show there can be substantial harms,” he says.
Those harms include bacterial infections, inadvertently poking holes in the colon or creating inflammation inside the gastrointestinal (GI) tract. There are even some case reports of death. “If the force used to administer the colonic is too great, that can cause a perforation that allows fecal material to enter the abdominal cavity and cause an overwhelming infection, and patients have died from that,” Cash says.
He points out that the term “colon cleansing” also refers to oral pills or supplements that purportedly rid your body of harmful junk. These also provide no proven benefit, though they do carry a risk for “electrolyte imbalances, kidney damage or a disruption of the microbiota of the GI tract,” he explains.
Other experts who have looked into colon cleanses agree. “Claims touting improved health, enhanced immunity or ‘detoxification’ are not supported by the evidence,” says Dr. Ranit Mishori, a professor of family medicine at Georgetown University School of Medicine.
In a study she published in the Journal of Family Practice, Mishori explains that the practice of cleansing or “detoxifying” the colon has been around for centuries. In 1919, she writes, the American Medical Association published a paper condemning the practice. Doctors have been trying to dissuade their patients from trying it ever since (often to no avail).
“People spend a lot of money on cleanses, looking for some magic bullet that would help them feel better,” she says. “The only ones set to benefit from cleanses are the manufacturers and sellers [of these products].”
Cash says much of the public interest in colon cleansing revolves around two common misconceptions. The first is the idea that your GI tract “is like pipes or plumbing, and that over time waste cakes the pipes or accumulates in the tubes of the GI tract,” he says. “You see these product commercials claiming that you have 20 pounds of waste adhering to the lining of your GI tract, but that’s not true.”
The second misconception, according to Cash, is the idea that your body is contaminated with toxins from your GI tract. He says your gut—as well as your liver, kidneys and immune system—are all designed to keep your body free of bacteria and harmful agents. Pumping yourself full of so-called cleansers, either orally or anally, is more likely to throw off than bolster your internal decontamination processes, he says.
But there are times when doctors may introduce fluid or other substances into your rectum. When screening for colon cancer or some other GI issues, a doctor may need to clear your colon of waste products in order to get a clear view, Mishori says. Other evidence shows that fecal transplants may be effective for specific medical conditions.
Also, for people who suffer from constipation, “medically supervised enema therapies may provide some temporary relief,” Cash says. “But usually that’s for a chronic issue.” For a temporary bout, lifestyle changes—like adding fiber to your diet—usually resolve things, he says.
Apples, not enemas. Spread the word.
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