The liver is a storehouse of a wide number of chemical and metabolic functions. Optimum functioning of the entire body depends largely upon the health of the liver. Apart from regularization of bodily functions, the liver also has a unique ability to regenerate its own tissues. It also performs the most important task of the metabolism of proteins, fats, and carbohydrates from the food that we eat.
Who is Advised A Liver Function Test?
- As a part of routine medical screening and health checkup
- A patient who presents with signs and symptoms indicate a liver disorder which needs to be diagnosed appropriately. Such signs and symptoms include:
➢ Unusual abdominal pain on the right side
➢ Nausea, vomiting
➢ Prolonged fever
➢ Unexplained weight loss
➢ Icterus (yellow discoloration of the skin and sclera)
➢ Pale colored urine
➢ Clay-colored stools
➢ Presence of abnormal bruise marks on skin or unusual bleeding
- As a follow-up test for patients having liver diseases in order to monitor the effects of treatment and progress of the disease
- To monitor adverse effects of certain medications on the liver (medications affecting liver function are mentioned below)
- Patients who have acute illnesses which may also affect the liver such as dengue, malaria, acute hepatitis.
- Patients who are exposed to environmental toxins such as lead, copper, iron.
- Patients who have a family history of some liver disorder
- Patients having a gall bladder disease
- Alcoholic patients
- Patients who have other systemic illnesses such as diabetes, metabolic syndrome, hypertension, dyslipidemia.
Drugs And Prescription Medications Which Are Known To Affect Liver Function Are
- Valproic acid
- Synthetic retinoids
- Anti-tubercular drugs
- Chemotherapy drugs
- Herbal medications
- Illicit drug abuse
When advised to undergo a liver function test, the first question asked by such patients is what food to avoid before the test and how to prepare for a liver function test. Before understanding how to prepare for the liver test, it would be worthwhile to know in brief regarding liver function test itself.
What is A Liver Function Test?
As the name suggests, a liver function test is a blood test done to assess the functioning of the liver by measuring various parameters.
The table below mentions parameters of a liver function test along with their normal range:
|Sr. No.||Liver Function Test Parameter||Normal Range|
|1.||Total Bilirubin||0.3 – 1.3 mg/dl|
|2.||Conjugated Bilirubin||0.1 – 0.4 mg/dl|
|3.||Unconjugated Bilirubin||0.2 – 0.9 mg/dl|
|4.||Aspartate Aminotransferase (SGOT)||12 – 38 U/L|
|5.||Alanine Aminotransferase (SGPT)||7 – 41 U/L|
|6.||Alkaline Phosphatase||40 – 125 U/L|
|7.||Total Proteins||5.2 – 8.2 g/dl|
|8.||Serum Albumin||2.4 – 4 g/dl|
|9.||Serum Globulin||2 – 3.5 g/dl|
|10.||Prothrombin time (PT)||11 – 13.5 seconds|
|11.||Gamma Glutamyl transferase||9 – 85 U/L|
Even a mild abnormality in liver function test values can be a result of an underlying liver disorder which needs to be evaluated and treated accordingly.
Foods To Avoid Before A Liver Function Test
- Liver function test does not require any amount of prior fasting unless told by the doctor. Yet, this does not mean that anything and everything can be eaten before the test.
- Your doctor may advise you to stop certain medicines (if you are on any) before the test. This is because some medications tend to interfere with test results.
- You may also be required to stop health supplements at least 12-24 hours before a liver function test.
- Drink plenty of water before the test so your veins are well hydrated and easier to find to draw a blood sample. This applies for every other blood test too.
- As far as possible, schedule your blood test in the morning itself so that you can avoid excess fasting and carry on with your routine immediately after the test.
Dietary restrictions before reporting for a liver function test are certainly a major part of preparing for the test. The reason why avoiding certain foods is important is because these foods tend to commonly affect the enzyme levels and give false-positive results.
Food eaten even on the previous night of a liver function test can influence test results. The liver is solely responsible for proteins, carbohydrate and fat metabolism. Therefore, in order to achieve accurate test results, there are certain foods to be avoided before going for a liver function test.
List Of Foods That Tend To Affect Liver Function Test Results Are
- Strictly avoid alcohol even 12-24 hours before a liver function test. The reason being, alcohol can affect blood glucose and fat levels giving incorrect results.
- Avoid cigarette smoking. The rule of avoiding alcohol and cigarette smoking does not just apply to liver function test, but to all other blood tests in general.
- Avoid eating a high protein diet before the test. Studies have shown that consuming a high protein diet shortly before a liver function test result in elevated transaminase.
- Transaminase (liver enzymes SGOT and SGPT) is also found to be higher in patients who consume a high carbohydrate diet before going for a liver function test.
- Eating foods that are rich in Vitamin K such as spinach, broccoli can temporarily raise prothrombin time. Hence, avoid excess intake of these just before a liver function test.
- Avoid eating a full heavy meal before going for the test. This is because blood levels of enzymes, nutrients, electrolytes, and vitamins are temporarily raised after eating a full meal.
Let your doctor know if you happen to eat any of the foods mentioned above, or consume alcohol or take any of the prescription medications which you have been told not to, on the previous night or just shortly before the liver function test so that the test can re-scheduled and you can be well prepared when you report for the next test and inaccurate test results can be avoided.