All you need to know about testing Gamma-Glutamyl Transferase levels with a laboratory test
19.4% of people tested have Gamma-Glutamyl Transferase levels which are too high.
And 1.2% have levels that are too low.
The average Gamma-Glutamyl Transferase result is 49.5 U/L
Note what is normal for you may differ for your age and sex.
The enzyme Gamma-Glutamyl Transferase (GGT) is found throughout the body, but it is most concentrated in your liver.
This makes a GGT blood test very useful helping to assess liver function and general health.
GGT levels are usually low, but can rise following liver damage. A GGT test is also particularly sensitive to detecting bile duct problems and levels can be acutely affected by alcohol consumption
By buying a laboratory test kit with professional nurse or clinic collection, you can accurately measure Gamma-Glutamyl Transferase for total reassurance.
Professional analysis in an accredited laboratory ensures rapid result delivery.
The Vitall Liver Function nurse or clinic test kit includes a Gamma-Glutamyl Transferase test and is available for just £59.00.
Tests which include a Gamma-Glutamyl Transferase test:
High levels of Gamma-Glutamyl Transpeptidase (GGT) are commonly seen in people who drink large amounts of alcohol or use drugs that can damage the liver. In early liver damage, GGT levels can rise and may return to the reference range if the cause is removed. After a certain point, liver damage can be irreversible, and a return of GGT to normal does not necessarily mean the liver is healing or has healed.
Raised GGT concentrations suggest that something is affecting the liver, but they are not specific to one particular cause.
Several medicines can increase GGT in the blood, including nonsteroidal anti-inflammatory drugs (NSAIDs), lipid-lowering drugs, antibiotics, histamine blockers, antifungal agents, anticonvulsants, antidepressants, and hormones such as testosterone. These increases do not necessarily indicate liver damage, and GGT levels alone cannot distinguish the cause.
Very high GGT, particularly when other liver enzymes are also increased, is generally treated as clinically significant and is often reviewed further to clarify the cause.
Low or normal results are not usually considered significant, and they suggest that liver disease is less likely.
When someone is otherwise well, low GGT levels are commonly not associated with any specific follow-up.
Measure your Gamma-Glutamyl Transferase levels and assess liver damage and your risk from liver disease with a Liver Function nurse or clinic finger-prick bloodtest kit
You get the convenient testing with the reassurance of professional clinical analysis. Your results are delivered quickly & securely online.
This Liver Function Test is advised if you:
The GGT test measures your levels of Gamma-Glutamyl Transferase (GGT), also known as gamma-glutamyl transpeptidase. GGT is an enzyme that is commonly found in the liver and, similar to other enzymes, it helps to speed up chemical reactions throughout the body. Typically, the GGT test alone will not be enough to diagnose or rule out a condition; for this reason, the GGT test is indicated alongside other liver enzymes (liver function tests).[1][2]
GGT plays an essential role in the regulation of glutathione, one of the body’s most important antioxidants. Therefore, GGT may rise or fall according to the levels of free radicals and other dangerous substances in the cellular environment. In most situations, GGT exerts a protective effect by increasing glutathione levels to neutralise oxidative stress.[1] Aside from the liver, GGT can also be found in cells from the bile ducts, kidney tubules, pancreas, and intestine.[3]
Altered GGT levels are usually observed in people with liver or biliary problems; however, it may also be elevated in patients with other conditions, such as chronic obstructive pulmonary disease or kidney disease.[3]
Considering that GGT is abundant in the liver, this test is commonly indicated if your GP suspects that you may have liver damage. Nonetheless, it can be used during the differential diagnosis of conditions that involve the gallbladder and the bile ducts.
You may need a GGT blood test if you have any signs or symptoms of liver or bile duct-related problems. The most common symptoms include jaundice, pain near the liver (upper right abdomen), nausea, vomiting, and feeling tired. The GGT test is usually accompanied by other liver function tests.[2][4]
Alcohol is a widely known hepatotoxin (liver toxin); it produces liver damage, which may increase GGT. For this reason, the excessive consumption of alcohol often requires testing. In certain situations, your GP may indicate this test to check if you have stopped drinking.[1] Using certain drugs may alter GGT levels too; in many cases, this occurs without liver damage if taken accordingly.[4]
The concentration of GGT in your blood is measured in units (U) per litre (L), and its reference ranges may vary among different populations, especially between different sexes and ages.[5] The exact range may also vary across different countries, regions, and laboratories:
You should always check the reference ranges from your laboratory; if your results are only slightly above or below the reference range, you may discuss it with your GP to see if it is significant or not. Having a normal GGT means that your tissues are not producing or releasing an excessive amount of this enzyme, which possibly means that you do not have liver or bile duct damage. Do not forget that medical examination and other studies may be required to completely discard damage or disease.
A high GGT usually indicates one of two things: tissue damage or GGT induction. Each mechanism has different causes and consequences.
Most conditions that involve direct injury or inflammation will produce an imbalance between highly reactive chemicals (free radicals and reactive oxygen species) and antioxidants; to protect themselves from these toxic substances, tissues like the liver may increase GGT production.[1]
In the case of tissue damage, GGT is released from damaged cells into the bloodstream at a higher rate. The damage can be caused by a drug, toxin, or disease; for example, people with alcohol-related liver damage may present a high GGT due to alcohol’s toxicity. Nonetheless, not every liver or bile duct disease will obligatorily result in high GGT. For certain conditions, GGT levels may be directly related to how severe the damage is.[1]
Certain drugs or substances can increase GGT levels, and this usually occurs without causing damage to any organ. These drugs may function as ‘inductors’, increasing the activity or production of GGT in the liver. If you are using a drug that may increase your GGT levels, your GP may ask you to interrupt the medication for a couple of days before the test; your GP may also indicate other liver function tests to discard or confirm liver damage.[4]
By itself, a high GGT should not cause alarm — it is preferable to interpret this test alongside other liver function tests, as well as a medical examination.
For a better understanding, high GGT levels should not be regarded as an injury but as a response. In some circumstances, the response is temporary, and GGT levels come back to normal without long-term consequences; a typical example is mild viral hepatitis.
If the cause involves an intense or prolonged injury, it may result in chronic conditions and altered function. Even though GGT levels will usually go back to normal levels a couple of weeks or months after the treatment, there may still be permanent damage. Studies have also found that patients with higher GGT may be more likely to develop chronic or severe liver disease.[1] Some conditions that can lead to significant damage include hepatic cirrhosis, biliary obstruction, and severe viral hepatitis.[3]
Recent studies have found that high GGT levels may be related to increased risk of cardiovascular disease, arterial hypertension, heart failure, and arrhythmias. However, scientists are unsure about how GGT could influence the development of these conditions.[6] High GGT has also been linked to diabetes, metabolic syndrome, many types of cancer, and other conditions.[7] More research is required before adequately considering high GGT as a reliable risk factor for these conditions.
Lastly, GGT levels may rise as a response to certain drugs or substances, usually without causing tissue damage. Drinking alcohol a day or two before taking this test may also cause a temporary increase.[4]
Liver and bile duct problems are among the most common causes of high GGT, especially when related to alcohol consumption:
GGT levels may rise if you are using one or more of the following drugs: [4]
In recent years, studies have found that having a high GGT could be linked to multiple metabolic, cardiovascular, and oncological diseases. However, it is unknown whether high GGT causes these conditions or vice versa; as stated before, more research is required before drawing concrete conclusions. These conditions include arterial hypertension, metabolic syndrome, heart failure, atherosclerosis, and many types of cancer.[6][7] Smoking may also increase GGT levels.[4]
Most of the time, people with high GGT will present the same symptoms associated with common liver problems:
The first step towards reducing your GGT level is to identify what is increasing it. The most evident cause is liver damage, which may occur due to liver diseases, biliary problems, or consumption of substances at toxic levels. To diagnose it, your GP may indicate other liver function tests, as well as other exams depending on what they are suspecting.[2]
If the cause involves liver or bile duct problems, you may decrease your GGT levels by following these recommendations:
If you do not have a high GGT, but you want to prevent liver disease and other related problems, you may follow the previous recommendations. You may also prevent viral hepatitis by getting the hepatitis A[8] and hepatitis B vaccines.[9]
If one of your medications is the cause, your GP may ask you to interrupt it or change it for another drug. It is important to discuss your plans with your GP before making decisions that may impact your health; avoid initiating or quitting any treatment without consulting your GP first.
GGT levels will usually go back to normal once the problem is treated; this may take a few days or weeks, depending on the cause.
In the case of GGT induction, which occurs by using certain drugs or substances, your GGT levels may go back to normal a couple of days after stopping such usage. For this reason, your GP may ask you to stop certain medications or avoid drinking alcohol a day or two before taking this test.[4] Avoid stopping your medication without consulting your GP.
If you have tissue damage, your GGT levels may take a longer time to return to normal. Especially in the case of heavy alcohol consumption, your GGT levels may take at least a month of abstinence before going back to normal levels.[4]
The sample can be taken directly from a vein with a needle or by a finger-prick sampling methd. For an adequate diagnosis, the GGT test should be taken alongside other liver function tests. Vitall offers the Liver Function Home Test Kit, a fingerprick test that includes GGT, alanine aminotransferase (ALT), albumin (ALB), alkaline phosphatase (ALP), bilirubin, globulins, and total protein (TP).
A fingerprick Vitall GGT test is a very simple way of testing yourself from home and getting accurate results online. Taking the sample is very easy, too. After washing your hands, you can take a lancet and press it firmly against the skin of the selected area (usually the little finger). Wipe away the first drop of blood and fill the blood collection tube to the upper line. Then, secure the tube and gently turn it over five to ten times. Always remember to label your sample before sending it back in the Test Kit Box.
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Alanine Aminotransferase