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Dr. Christopher S. Baird

How do your intestines detox your body?

Category: Health      Published: November 19, 2014

By: Christopher S. Baird, author of The Top 50 Science Questions with Surprising Answers and Associate Professor of Physics at West Texas A&M University

Tylenol molecule
In too high of a concentration, the Tylenol molecule (shown above) becomes toxic to the human body. Since it is the liver's job to detoxify the body, Tylenol overdose leads to liver failure, not intestinal failure. Public Domain Image, source: Wikipedia.

The intestines are not the main organ that detoxifies the human body. That function is carried out mainly by the liver. It is the function of the intestines to absorb nutrients from the food you eat and excrete food that your body does not absorb. Although all cells have the ability to metabolize chemicals, it is mainly the job of the liver to metabolize chemicals that are particularly dangerous or that accumulate to particularly dangerous levels.

The word "detoxify" (or "detox" for short) is a vague word that is loaded with many pseudo-scientific connotations. In a scientific context, the word "detoxify" means to remove or dismantle specific chemicals that can harm the body if their concentration is too high. One of the liver's primary functions is to dismantle and deactivate dangerous chemicals before they build up enough to do damage. The liver is the body's natural detoxifier. But the liver is not infinitely powerful. If dangerous chemicals get too highly concentrated for the liver to handle, or if certain dangerous chemicals enter the body which the liver can't handle at all, they can damage the liver and even cause death. For an over-dose of certain chemicals, manual detoxification carried out by medical professionals can deactivate the toxins or counter the effects of the toxins before they damage the liver. The point is that it's the liver that gets damaged when you swallow 50 Tylenol pills at once, not the intestines. Long-term over-consumption of alcohol can lead to liver failure, not intestinal failure, because it is the liver that is breaking down the alcohol.

The textbook Hepatotoxicity by Hyman J. Zimmerman states, "The liver has long been credited with the responsibility for detoxification and considered the guardian of the body (1,2). However, appreciation of the protective role of the liver has been tempered by the recognition that some ‘detoxifying' changes may result in harmful products (3-10)."

The liver is a very hardy organ and does an amazing job of detoxifying the body. If a person is exposed to certain chemicals that the liver cannot handle, or to concentrations of chemicals that are higher than the liver can handle, then the person should be rushed to the emergency room immediately, since liver failure is often fatal. Doctors can manually remove some toxins from the blood using dialysis or can counter the effects of some toxins with other chemicals. In a worst case scenario, doctors can conduct a liver transplant to save the patient's life. If a person has neither an underlying long-term liver disease that requires medical attention, nor exposure to toxin levels that requires hospitalization, then the liver is doing its job of detoxification just fine. Generally healthy people don't need to have their livers or their bowels "cleansed", as many pseudo-scientific advocates claim. Do-it-yourself "detox diets", "bowel cleanses", and "liver cleanses" are non-scientific. They do nothing to detoxify your body of dangerous chemicals. They are not supported by any scientific evidence, and they even lack any physically-plausible mechanism by which they could work. The Mayo Clinic states,"Detox, or detoxification, diets are popular, but they're not scientifically proven... there's little evidence that detox diets actually remove toxins from the body. Indeed, the kidneys and liver effectively filter and eliminate most ingested toxins."

Topics: bowel, bowel cleanse, cleanse, detox, detox diet, detoxification, detoxify, intestines, liver, liver cleanse