GGT blood tests measure the amount of Gamma Glutamyl Transferase that is present in the blood. GGT is one of the liver enzymes that are usually restricted to the areas of the liver and some other organs but when there is some kind of liver disease, the levels of this enzyme increase because the enzyme starts to leak out of the liver into the bloodstream. There are other liver function tests that are usually conducted along with a GGT blood test to actually ascertain why the liver is damaged.
The GGT blood test is used when a patient comes into a doctor's office with visible signs of liver damage like jaundice. Jaundice is the first sign of liver damage because of the high levels of bilirubin in the blood. This substance is normally collected in the liver, processed and converted into a digestive juice called bile. When the liver is damaged, this function does not take place at all causing bilirubin to start accumulating in the blood stream. Jaundice can be caused either by a viral hepatitis infection from contaminated food and water sources or it can also be caused by alcoholism.
Elevated GGT levels themselves do not mean anything as the levels of GGT tend to fluctuate during the day; however, the presence of jaundice is usually confirmation enough of some kind of liver damage. A GGT test should then be compared with an ALP test.
Other liver enzyme tests include the ATP and ALT test as these are also some of the enzymes that start to leak out of the liver when there is liver inflammation.
If you are not an alcoholic, then the reasons for liver damage could be from consuming contaminated food or drink. The result is viral hepatitis. This is a problem that will take a month of complete bed rest and dietary modifications to cure. The dietary modification includes the elimination of fat from the diet completely and also reducing any spice that you could be taking. All of these tax the liver a great deal from a digestive system perspective. Alcohol induced, elevated GGT levels mean that it is probably time to reduce the amount of alcohol that you consume to zero. This is because any further abuse could cause cirrhosis of the liver.