• Published on: Sep 15, 2021
  • 5 minute read
  • By: Dr Rakesh Rai

Everything About Liver Function Tests- Purpose & Significance

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Everything About Liver Function Tests- Purpose & Significance

Liver function tests are medical laboratory tests that measure the number of various substances in the blood that are released into your blood by liver cells or made by your liver. These substances are often called "liver enzymes" because they are enzymes that are produced exclusively by the liver to help regulate metabolism for processing chemicals, nutrients, and drugs.

A high level of any one of these may suggest an abnormal situation involving your liver. The most common symptoms associated with a problem involving your liver include nausea, vomiting, yellowing skin color (jaundice), fever, and abdominal discomfort such as pain on gentle pressing around about halfway down on the right side of the abdomen.

A liver function test is a blood test that evaluates an individual's liver function or sees if there may be a problem in this organ. Liver functions including leukocyte count, alkaline phosphatase, ALT/AST enzymes, and bilirubin levels are measured with results interpreted by physicians who then advise treatment options to relieve pain or reduce the risk of liver disease. If the level of these agents is elevated then the physician will typically recommend further diagnostics such as antibody testing for hepatitis B and C infections, ultrasounds, and biopsies.

Liver function tests are a series of blood tests used to evaluate liver function. Tests may include the following:

  • Inclusion of serum albumin or total proteins as variables in the SMA12 test
  • Albumin fractional catabolic rate (ACR) and erythrocyte sedimentation rate (ESR) measurements, which can be used as a surrogate marker for changes in hepatocellular activity
  • Visible change is indicative that hepatocytes have been damaged or destroyed, an indicator that liver disease is present.
  • Fractional synthetic rate of albumin synthesis calculated from measurements of serum creatinine and urinary urea nitrogen providing information about hepatocyte intracellular mass status with decreased album

The most common of these are aminotransferases ALT and AST. These enzymes are released into the bloodstream in excessive amounts by the cells that line the bile ducts that carry bile from the liver - where it gets made - to where it gets used up in digestion ??i.e., all over your body, not just in your liver but also near your kidneys) when there's any sort of problem with those cells or with damage done to them because of some other hurtful event.

In the context of a medical lab test, a liver function test is anyone that has to do with the liver. Serum bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase are common ones. A veterinarian could use ultrasound as well as biochemistry analysis. These tests show how well your liver is performing its duty to remove toxins from your body and to make bile for those toxins.  Liver function tests are conducted to assess the liver's ability to convert inactive substances in your blood to active ones.

Alanine aminotransferase (ALT/SGPT): tests what process - amino acid, carbohydrate, or fat - your liver is having trouble breaking down to store sugar for later use indigestion. This test will only show what type of enzyme the liver has difficulty processing at this time, so if this is normal but an alkaline phosphatase test comes back abnormal, this means there may be a different illness affecting the liver.

The test can measure certain chemicals that are released because of metabolism and excreted from the body in urine, such as albumin.

The most common indicators measured by blood-based liver function tests include GGT, ALP, total bilirubin / conjugated/unconjugated bilirubin, ALT and ASAT.

A group of enzymes found in healthy livers called GOT (gamma-glutamyl transpeptidase) and GPT (gamma-glutamyltransferase) can also be measured to determine damage to liver cells.

Liver Function Tests (LFTs) are a group of tests that measure the levels and function of various substances in the blood leave before digestion and within the liver. These include enzymes and proteins made by the liver; cholesterol, copper, iron, calcium, sodium, potassium; bilirubin level; albumin levels. The LFTs can be used to help diagnose many diseases such as viral hepatitis or alcoholic liver disease.

A history would normally prompt additional testing such as abdominal imaging for gallstones or metabolic abnormalities like cirrhosis caused by alcohol consumption. Kidney function should be tested because high-protein diets may cause kidney problems too. A genetic test might be warranted if there is a family history of inheritance. Liver function tests are a group of blood tests that doctors might use to evaluate the liver's ability to gather and store glycogen (sugar) and protein, produce bile, filter the blood, and produce cholesterol.

Drugs can accumulate in liver cells, leading to changes in levels of enzymes. Enzymes that are elevated may indicate an inflammatory or viral process as well as the use of certain medications such as steroids which need some time to clear from the body after discontinuation. The test isn't specific for any disease but can show if there is a liver problem even before symptoms occur, including cirrhosis and early hepatitis B and C infections. When first conducted, rapid elevations or decreases might be indications of acute injury or pre-clinically chronic injury respectively.

The liver may be the body's most important gland. It synthesizes nutrients from fat, carbohydrates, and protein into a form that can be absorbed by the blood to supply the cells, brain, and other tissues with a continuous supply of fuel. The liver also acts as a storage center for high-density energy reserves in times of food shortage or famine.

In response to viruses or bacteria which enter from our gut through their ingestion of contaminated water or insects’ excretions for example), substances called antibodies are manufactured in great numbers by specialized cells in an inflammatory reaction known as acute hepatitis. LFT helps measure the liver's endurance, by testing erythrocyte count, serum albumin level, bilirubin level and prothrombin time.

It's normal for your erythrocyte count to drop over time as you age. This is due mainly to the production of fewer red blood cells in your bone marrow. It may provide an indication of what is happening inside the liver with regard to the regeneration of new cells. An elevated or persistently high level can indicate cirrhosis or cancer. If it's persistently high, then requires radiologic imaging for diagnosis.

The liver function tests are blood tests that tell the physician how well the liver is working. The enzymes GGT, ALT, AST, and ALP are primarily tested to examine what should be healthy activities through three phases of hepatic metabolism. Since these enzymes exist primarily in the liver, they do not normally show up in any other tissue or fluid other than the bloodstream. If there is a disease that affects the cells within the liver, then inflammatory processes will ensue. This will lead to excessive production of oxygen-free radicals to facilitate cell death and release toxins into circulation which can affect all body systems including altering enzyme quantities, so they bump up against their normal reference ranges for evaluation.

The purpose of liver function tests is to diagnose and monitor a person's condition, based on levels of certain enzymes in the blood.

A high level of transaminases might be due to a variety of diseases or conditions, including hepatitis, cirrhosis, biliary obstruction from gallstones, or pancreatitis. Liver disease disrupting the production and release of albumin will also produce abnormally low-level albumin which can be detected with this test. A qualitative determination can be made if large amounts of Clotting Factor VIII are released into the bloodstream - Hepaetous Patina (HP) - leading to severe bleeding episodes independent from coagulation defects where plasma clotting normally should take place.

Liver function tests measure the level of different substances produced or used by the liver, such as albumin. The liver conditions may include fatty liver (hepatic steatosis), alcoholic hepatitis, cirrhosis, and many disorders affecting other parts of the body which ultimately damage the working capacity of your liver. Liver function tests are not meant to detect acute hepatitis or mild cases of elevated enzyme levels that commonly resolve on their own. Normal results suggest that there is no abnormality with your kidneys. Abnormal livers often show high amounts of creatinine kinase (CK) and alanine aminotransferase (ALT).

The liver is the body's only organ able to break down toxic compounds, so its function must be checked. The example you gave -- SGPT, or aspartate aminotransferase -- measures the level of a major liver enzyme. High levels could indicate damage from drugs also used for weight loss, such as acetaminophen/paracetamol (Tylenol) or metformin (Glucophage). Too-low levels of hepatocyte enzymes mean that the liver's not functioning properly and may develop complications like hepatitis and cirrhosis.

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Importance of Liver Health for Overall Wellness: Why It Matters

The liver is one of the most vital organs in the human body, performing over 500 essential functions. Despite its importance, liver health is often overlooked until problems arise. Maintaining liver health is crucial for digestion, detoxification, metabolism and overall wellness.

In India, rising cases of fatty liver disease, alcohol-related liver damage and metabolic disorders highlight the need for greater awareness about liver care. Understanding the importance of liver health can help prevent long-term complications.

 

What Does the Liver Do?

The liver performs several key functions:

  • Filters toxins from the blood
     

  • Produces bile for digestion
     

  • Regulates blood sugar levels
     

  • Stores vitamins and minerals
     

  • Metabolizes fats, proteins and carbohydrates
     

  • Supports immune function
     

A healthy liver ensures the body functions smoothly.

 

Why Liver Health Is Important for Overall Wellness

1. Natural Detoxification

The liver processes harmful substances such as:

  • Alcohol
     

  • Medications
     

  • Environmental toxins
     

  • Metabolic waste products
     

Efficient detoxification prevents toxin buildup in the body.

 

2. Supports Digestion

The liver produces bile, which helps break down fats during digestion. Poor bile production may lead to:

  • Bloating
     

  • Indigestion
     

  • Nutrient absorption issues
     

 

3. Regulates Metabolism

The liver plays a major role in converting nutrients into energy. It regulates:

  • Blood glucose levels
     

  • Cholesterol production
     

  • Fat storage
     

Impaired liver function can disrupt metabolic balance.

 

4. Strengthens Immunity

The liver contributes to immune defense by removing bacteria and toxins from the bloodstream.

Chronic liver disease may weaken immune response.

 

5. Hormone Regulation

The liver helps regulate hormones, preventing imbalances that may affect mood and energy.

 

Common Liver Conditions

Fatty Liver Disease

Often linked to obesity and diabetes. Early stages may not show symptoms.

Hepatitis

Inflammation of the liver caused by viruses, alcohol or toxins.

Cirrhosis

Advanced liver scarring that impairs function.

Early detection improves outcomes significantly.

 

Early Signs of Liver Problems

Watch for:

  • Persistent fatigue
     

  • Yellowing of skin or eyes (jaundice)
     

  • Abdominal pain (right upper side)
     

  • Dark urine
     

  • Nausea
     

  • Swelling in legs
     

If symptoms persist, medical evaluation is essential.

 

Risk Factors for Liver Disease

  • Excess alcohol consumption
     

  • Obesity
     

  • Diabetes
     

  • High cholesterol
     

  • Viral hepatitis
     

  • Long-term medication use
     

Lifestyle factors strongly influence liver health.

 

How to Improve Liver Health Naturally

1. Maintain a Balanced Diet

Include:

  • Fresh fruits and vegetables
     

  • Whole grains
     

  • Lean protein
     

  • Healthy fats
     

Limit processed foods and sugary drinks.

 

2. Exercise Regularly

Physical activity reduces fat accumulation in the liver.

Aim for at least 30 minutes of exercise most days.

 

3. Avoid Excess Alcohol

Excess alcohol is a major cause of liver damage. Moderation or abstinence is recommended.

 

4. Stay Hydrated

Water supports detoxification processes.

 

5. Manage Weight

Healthy weight reduces risk of fatty liver disease.

 

6. Routine Health Screening

Periodic liver function tests (LFTs) help detect abnormalities early.

 

Liver Health in the Indian Context

Non-alcoholic fatty liver disease (NAFLD) is becoming increasingly common in urban India due to sedentary lifestyle and dietary habits. Public awareness about preventive care is essential to reduce long-term complications such as cirrhosis and liver failure.

 

When to Seek Medical Help

Consult a healthcare professional if you experience:

  • Persistent jaundice
     

  • Severe abdominal pain
     

  • Unexplained weight loss
     

  • Swelling in abdomen
     

  • Chronic fatigue
     

Early intervention prevents serious outcomes.

 

Conclusion

The importance of liver health for overall wellness cannot be overstated. The liver plays a central role in detoxification, digestion, metabolism and immune function. Maintaining liver health through balanced nutrition, regular exercise and responsible lifestyle habits supports long-term wellbeing.

Early detection of liver issues allows timely treatment and prevents complications. Protecting your liver today ensures a healthier future.

 

References

  • Indian Council of Medical Research – Liver Disease Reports
  • World Health Organization – Hepatitis and Liver Health Guidelines
  • National Institute of Nutrition India – Dietary Guidelines
  • Indian Journal of Gastroenterology – Fatty Liver Studies
  • Lancet Global Health – Liver Disease Research

 

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