Liver profile testing is useful for determining how well you are able to handle toxic substances. The liver is responsible for transforming toxic substances into harmless by-products that the body can excrete. It does this in a variety of ways, including acetylation, conjugation, sulfation, sulfur transferase, and via the cytochrome P450 system.

The functional liver profile looks at the total toxic load in your body and sees how well your body handles it by measuring the abilities of your liver detoxification systems. When we are exposed to substances that the body sees as toxic, cytochrome P450 levels go up.

The cytochrome P450 system, called phase 1 liver detoxification, transforms endotoxins (toxins produced within the body) and exotoxins (those taken into the body from outside) into water-soluble forms that can be excreted in urine.

By measuring the cytochrome P450 levels and seeing how quickly the toxic materials are transformed, tests can provide useful information about how well the body is able to detoxify a wide variety of substances.

Many substances can stimulate cytochrome P450 production, including alcohol, barbiturates, carbon tetrachloride, charcoal broiled meats, dioxin, exhaust fumes, high protein diets, niacin, oranges, organophosphorus pesticides, paint fumes, riboflavin, sassafras, saturated fats, steroid hormones, sulfonamides, and tangerines.

When cytochrome P450 is released, a second phase of detoxification is also activated, which causes an elevation of D-glucaric acid. D-glucaric acid is released by the liver and is a by-product of turning toxic substances into glucuronidase, which is excreted in urine.

A sulfur/creatinine ratio is used to test this function. This ratio helps determine leaky gut syndrome, low glutathione levels, and the level of free radical activity. For the test, take small amounts of caffeine, aspirin, and acetaminophen at home and send urine samples off to the laboratory for analysis.

By measuring your urine and saliva, your liver’s ability to process toxins can be determined. Normal levels of cytochrome P450 are found in 50 percent of people tested. A low-caffeine clearance is found in about one-third of all people tested and indicates that your body is having difficulty detoxifying.

Highcaffeine clearance levels are found in people who have been exposed to high levels of toxins or smoke. Another way to measure liver detoxification pathways is to measure D-glucaric acid and mercapturic acid in the urine. D-glucaric acid is a general marker for cytochrome P450 liver detoxification pathways.

High levels of D-glucaric acid indicate the presence of environmental toxins such as pesticides, herbicides, fungicides, petrochemicals, and excessive alcohol intake. Mercapturic acid provides a measurement of glutathione conjugation. This test is easier on those who do not tolerate caffeine, aspirin, or acetaminophen.