• 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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National Dentist Day 2025

National Dentist Day: Best Oral Hygiene Tips Shared by Experts

Every year, on March 6th, National Dentist Day is celebrated to recognize the invaluable contributions of dentists in maintaining our oral health. This special day also serves as a reminder of the importance of good oral hygiene habits. Whether you're looking to improve your daily dental routine or seeking expert advice, we’ve compiled the best oral hygiene tips shared by dentists to help you achieve a healthy and confident smile.

1. Brush Properly, Not Just Regularly

Brushing twice a day is essential, but how you brush matters just as much as how often. Experts recommend using a soft-bristled toothbrush and fluoride toothpaste. Follow these steps for effective brushing:

  • Use a gentle, circular motion rather than scrubbing.

  • Brush for at least two minutes twice a day.

  • Ensure you clean all tooth surfaces, including the back molars and gum line.

2. Flossing is Non-Negotiable

Flossing removes food particles and plaque from between your teeth where your toothbrush can’t reach. Dentists suggest flossing at least once a day to prevent cavities and gum disease. If traditional flossing is difficult, consider using:

  • Water flossers

  • Interdental brushes

  • Floss picks

3. Rinse with Mouthwash for Extra Protection

Using an antibacterial mouthwash helps reduce plaque, prevents bad breath, and protects against gum disease. Look for a fluoride-based or alcohol-free mouthwash, especially if you have sensitive gums.

Tip: Rinse for 30 seconds after brushing and flossing for best results.

4. Eat a Tooth-Friendly Diet

What you eat significantly impacts your oral health. Dentists recommend incorporating the following foods into your diet:

  • Dairy products (milk, cheese, yogurt) to strengthen enamel.

  • Crunchy fruits and vegetables (apples, carrots) to naturally clean teeth.

  • Nuts and seeds for essential minerals like calcium and phosphorus.

  • Green tea for its antibacterial properties.

Avoid excessive consumption of sugary snacks, acidic beverages, and sticky candies, which can erode enamel and lead to cavities.

5. Stay Hydrated and Limit Sugary Drinks

Drinking plenty of water helps wash away food particles and bacteria, keeping your mouth fresh and clean. Limit soda, sports drinks, and coffee, as they can stain teeth and contribute to decay.

Pro Tip: If you drink sugary or acidic beverages, use a straw to minimize direct contact with your teeth.

6. Replace Your Toothbrush Regularly

A worn-out toothbrush is ineffective at cleaning your teeth. Dentists recommend replacing your toothbrush every 3-4 months or sooner if the bristles are frayed. Using an electric toothbrush can also improve plaque removal.

7. Schedule Regular Dental Checkups

No matter how diligent your oral hygiene routine is, visiting your dentist every six months is crucial for professional cleanings and early detection of dental issues. Regular checkups can help prevent cavities, gum disease, and even serious health conditions linked to poor oral health.

8. Protect Your Teeth While Playing Sports

If you engage in contact sports, wearing a custom-fitted mouthguard can protect your teeth from injuries and fractures. This simple preventive measure can save you from costly dental treatments.

9. Avoid Smoking and Tobacco Products

Smoking and tobacco use are major contributors to gum disease, tooth loss, and oral cancer. If you’re looking for another reason to quit, your oral health is a great motivation. Talk to your dentist about resources to help you quit.

10. Teach Kids Good Oral Hygiene Habits Early

Children should learn proper oral hygiene habits from a young age. Encourage them to:

  • Brush their teeth with fluoride toothpaste.

  • Floss regularly.

  • Visit the dentist every six months.

  • Avoid excessive sweets and sugary drinks.

Setting a strong foundation for oral health can prevent future dental issues and ensure a lifetime of healthy smiles.

Conclusion

This National Dentist Day, take the opportunity to improve your oral care routine by following these expert tips. Good oral hygiene isn’t just about having a bright smile—it’s also essential for overall health and well-being. Show appreciation for your dentist by prioritizing your dental health and scheduling your next checkup.

For personalized dental care advice, consult a professional at SecondMedic, where expert guidance helps you maintain optimal oral health.

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