• 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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Inflammation

How Inflammation Affects Overall Health: Understanding the Hidden Risks

Inflammation is often misunderstood. While it is a vital protective response of the immune system, persistent or chronic inflammation can quietly damage tissues and increase the risk of serious diseases. Understanding how inflammation affects overall health is crucial in preventing long-term complications and maintaining optimal wellbeing.

According to the World Health Organization and global medical research published in Lancet, chronic inflammation is linked to a wide range of non-communicable diseases, including heart disease, diabetes and autoimmune disorders.

 

What Is Inflammation?

Inflammation is the body’s natural response to:

  • infection

  • injury

  • toxins

  • stress

It activates immune cells to eliminate harmful stimuli and promote healing.

There are two main types:

Acute Inflammation

Short-term and protective.
Examples include swelling after injury or fever during infection.

Chronic Inflammation

Long-term, low-grade inflammation that persists even without injury.

Chronic inflammation is harmful.

 

How Chronic Inflammation Develops

Persistent inflammation can result from:

  • unhealthy diet

  • sedentary lifestyle

  • obesity

  • chronic stress

  • environmental toxins

  • untreated infections

Modern lifestyle patterns contribute significantly to this condition.

 

Impact on Heart Health

Inflammation damages blood vessels and promotes plaque formation.

This increases risk of:

  • heart attack

  • stroke

  • hypertension

ICMR data highlights cardiovascular disease as a leading cause of death in India, with inflammation playing a contributing role.

 

Link Between Inflammation and Diabetes

Chronic inflammation interferes with insulin signalling.

This leads to:

  • insulin resistance

  • elevated blood sugar

  • metabolic syndrome

NFHS-5 data shows rising diabetes prevalence, partly linked to inflammatory lifestyle factors.

 

Effect on Joint and Muscle Health

Inflammatory processes contribute to:

  • arthritis

  • joint stiffness

  • muscle pain

Autoimmune diseases often involve chronic inflammation.

 

Gut Health and Inflammation

The gut plays a central role in immune regulation.

Poor diet and stress disrupt gut balance, triggering:

  • inflammatory bowel conditions

  • digestive discomfort

  • nutrient malabsorption

Gut inflammation impacts systemic health.

 

Brain Health and Inflammation

Emerging research suggests chronic inflammation affects:

  • memory

  • mood

  • cognitive performance

Inflammatory markers are associated with depression and neurodegenerative disorders.

 

Chronic Fatigue and Inflammatory Stress

Persistent inflammation causes:

  • ongoing fatigue

  • reduced stamina

  • sleep disturbances

The immune system remains in constant activation mode.

 

Role in Autoimmune Disorders

Autoimmune diseases occur when the immune system mistakenly attacks healthy tissues.

Chronic inflammation is central to conditions such as:

  • rheumatoid arthritis

  • lupus

  • inflammatory bowel disease

 

Signs of Chronic Inflammation

Symptoms may include:

  • unexplained fatigue

  • persistent joint pain

  • digestive issues

  • frequent infections

  • skin problems

Early detection is important.

 

Lifestyle Factors That Increase Inflammation

High Sugar Intake

Excess sugar promotes inflammatory pathways.

 

Processed Foods

Trans fats and additives trigger immune responses.

 

Sedentary Lifestyle

Lack of exercise reduces anti-inflammatory benefits.

 

Poor Sleep

Sleep deprivation increases inflammatory markers.

 

Chronic Stress

Elevated cortisol disrupts immune balance.

 

Natural Ways to Reduce Inflammation

Anti-Inflammatory Diet

Include:

  • leafy greens

  • fruits rich in antioxidants

  • nuts and seeds

  • whole grains

Avoid excessive processed foods.

 

Regular Physical Activity

Exercise lowers inflammatory markers and improves circulation.

 

Stress Management

Meditation and breathing exercises reduce stress hormones.

 

Adequate Sleep

7–8 hours of quality sleep supports immune regulation.

 

Maintain Healthy Weight

Excess abdominal fat produces inflammatory chemicals.

 

Role of Preventive Health Screening

Regular tests such as:

  • blood sugar

  • lipid profile

  • inflammatory markers

help monitor risk factors early.

 

Importance of Early Intervention

Unchecked inflammation increases risk of:

  • cardiovascular disease

  • metabolic disorders

  • organ damage

Timely lifestyle changes reverse early inflammatory effects.

 

Long-Term Health Benefits of Inflammation Control

Reducing inflammation supports:

  • heart health

  • stable blood sugar

  • improved immunity

  • enhanced cognitive function

  • reduced pain

Preventive strategies protect long-term wellbeing.

 

Conclusion

Understanding how inflammation affects overall health reveals its profound impact on the heart, brain, gut and metabolic systems. While acute inflammation protects the body, chronic inflammation silently contributes to major diseases. Fortunately, lifestyle changes such as balanced nutrition, regular exercise, quality sleep and stress management significantly reduce inflammatory burden. Prevention and early monitoring remain the most effective tools for protecting overall health and ensuring long-term vitality.

 

References

  • World Health Organization (WHO) – Chronic Disease and Inflammation Reports

  • Indian Council of Medical Research (ICMR) – Cardiovascular and Metabolic Health Studies

  • National Family Health Survey (NFHS-5) – Diabetes and Hypertension Data

  • NITI Aayog – Preventive Healthcare Strategy Reports

  • Lancet – Inflammation and Chronic Disease Research

See all

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