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Every drug, pesticide, hormone, food sub-
stance and chemical is broken down or meta-bolized by the liver cells. If these substances are not processed by the liver, they will be stored in the fat tissues and cell membranes of the body. The danger of these substances being stored is that they will be released during exercise, stress, and fasting and can then hurt the body. This can cause unwanted symptoms like headaches, stomach pain, and nausea (feeling sick in the stomach). If these potentially harmful substances are not broken down, they can build up in the blood, which creates more work for the immune system.
Sometimes, when the liver processes a substance, the substance is activated rather than broken down. If this happens, the liver will produce toxic by-products that may hurt the body. For example, when the liver processes acetaminophen (Tylenol®), substances that are bad for the body are produced.
In order to break down bad substances, the liver has two detoxification pathways. Generally, the detoxification pathways change chemicals that dissolve in fat (fat-soluble chemicals) into chemicals that dissolve in water (water-soluble chemicals). Only chemicals dissolved in water can be easily removed from the body in water-based fluids such as urine and bile. The diagram below gives a simplified version of this process.
Detoxification Process
The first pathway in the detoxification process is called Phase One. In this pathway, a harmful chemical is changed to a less harmful one through a series of chemical reactions. Throughout the process, free radicals are made. Free radicals are unstable particles that react with the body and damage the body’s cells. Free radicals can be caused by pollution, radiation and food preservatives as well as sources inside the body like HIV, or even the body itself. If there are too many free radicals, damage may occur to the liver cells. How well your body gets rid of free radicals depends to a large degree on the kind of food you give your body.
After the toxic chemical has gone through and been changed by the Phase One pathway, it moves on to the second pathway called Phase Two. In this pathway, the liver cells add a substance to the toxin to make it water-soluble. Water-soluble substances (easily dissolved in water) can then be removed from the body through urine and feces.