Liver Functions: What Your Liver Does and How to Protect It

Your liver is one of the body's busiest organs, with hundreds of jobs that keep you well. Its main liver functions are making bile to digest fats, processing nutrients from food, storing energy, making proteins and clearing toxins, alcohol and medicines from your blood. Knowing these liver functions helps you understand a blood test result, spot the signs of a problem early and look after your liver for life.

Key takeaways

• The liver digests fat, stores energy, makes proteins and breaks down alcohol and medicines.
• Liver disease often causes no symptoms until it is advanced.
• Fatty liver disease, alcohol and viral hepatitis are the most common causes in Australia.
• A liver function test is a simple blood test, and most liver damage can improve if the cause is treated early.

The Main Liver Functions in Your Body

The liver sits in the upper right of your abdomen, tucked under the ribs, and it's the largest organ inside the body. Where is the liver located in the body, exactly? Just below the diaphragm, beside the stomach and in front of the right kidney. These are the functions of the liver that matter most for your health:

The liver also plays a part in digestion, metabolism, cholesterol and the immune system, and it can regrow after some kinds of damage.

Symptoms of a Liver Problem

A liver problem often causes no symptoms at first, because the liver keeps working until much of it is damaged. When liver functions start to fail, you may notice tiredness, nausea, loss of appetite, itchy skin, yellowing of the skin or the whites of the eyes (jaundice), dark urine, pale stools, easy bruising, and swelling of the belly or legs. Hepatitis, an inflammation of the liver, can cause a flu-like illness with aches and fever, and hepatitis from a virus may be passed on to others. Because the liver also handles the fat and nutrients absorbed by the small intestine, some people lose weight or feel run down. Confusion or drowsiness in someone with liver disease is serious and needs urgent care.

Common Causes of Liver Disease

The most common cause of liver disease in Australia is fatty liver disease, where fat builds up in the liver. What is fatty liver disease? It's now called metabolic dysfunction associated steatotic liver disease, and it's linked to excess weight, type 2 diabetes, high blood glucose and high cholesterol. It affects about one in three Australian adults, and most don't know they have it. Over years, the fat can cause inflammation and scarring.

Alcohol is the next most common cause, followed by hepatitis B and hepatitis C, which are viral infections. Other causes of liver disease include some medicines and supplements, too much paracetamol, an inherited iron overload called haemochromatosis, autoimmune hepatitis, and gallstones that block the duct from the gallbladder. Everything you eat and drink passes through the liver, which is why diet and alcohol matter so much to your liver functions.

Symptoms of liver disease from any of these causes are often vague until late, which is why a blood test is the usual first clue.

What a Liver Function Test Measures

A liver function test, or LFT, is a blood test that checks how well your liver is working and whether it's under strain. It measures liver enzymes (ALT, AST, GGT and ALP), which rise when liver cells or the bile ducts are irritated or damaged, and bilirubin, a yellow pigment the liver clears into bile. It also measures albumin and total protein, which show how well the liver makes proteins, a vital job of the organ. Raised enzymes can point to fatty liver, alcohol, hepatitis or a medicine, and a raised ALP with bilirubin can point to a blocked bile duct or a problem with the gallbladder. Your doctor may add a blood glucose, a clotting test or a hepatic ultrasound, which looks at the liver itself.

Next Steps After an Abnormal Liver Test

A slightly abnormal result is common and often settles, so the usual first step is a repeat test in a few weeks, after cutting back on alcohol and reviewing your medicines. If it stays abnormal, your doctor may test for hepatitis B and C, iron overload and autoimmune causes, and arrange an ultrasound of the liver and the area around the stomach. A special scan that measures liver stiffness can show whether scarring has started. Bilirubin that isn't excreted properly can make you jaundiced, and that needs prompt review. If results are well outside the range, your doctor may refer you to a specialist in hepatic disease, and rarely a small sample of liver tissue is taken to look at its lobules under a microscope.

Ways to Protect Your Liver

Most liver damage is preventable. Keep to Australia's alcohol guideline of no more than 10 standard drinks a week and no more than 4 on any one day, and have some alcohol-free days. Keep a healthy weight, especially around the abdomen, and stay active, which reduces fat in the liver. Get vaccinated against hepatitis B, and never share needles, razors or toothbrushes, which can spread hepatitis C. Take paracetamol and other medicines only at the dose on the pack, and tell your doctor about any herbal supplements, because some harm the liver. A diet rich in vegetables, wholegrains and lean protein, and low in sugary drinks, also lowers the risk of gallstones, which can block the bile duct.

When to See a Doctor About Your Liver

See a doctor if you notice yellow skin or eyes, dark urine or pale stools, ongoing itch, swelling of your belly or legs, or ongoing tiredness with nausea. See one too if you drink more than the guideline, have diabetes or excess weight, or were born in a country where hepatitis B is common, because a check can find liver disease early. Lifestyle changes and treatment can often reverse early damage, and only a small number of people ever need a liver transplant. Call 000 or go to an emergency department for vomiting blood, black stools, severe abdominal pain, confusion or extreme drowsiness. If someone has taken too much paracetamol or other substances, call 000 or the Poisons Information Centre on 13 11 26 straight away, even if they feel well.

Summary

This guide covered the main liver functions, the signs of a problem, the common causes of liver disease, and the blood test that checks your liver. If you're worried about your liver functions, a Medio GP can talk it through by phone, request a liver function test if they think you need one, and refer you to a specialist if it's right for you.

Frequently asked questions

Where is the liver located in the body?

The liver is located in the upper right of your abdomen, under the lower ribs and just below the diaphragm. What does the liver look like? It's a reddish brown, wedge-shaped organ about the size of a rugby ball, weighing around one and a half kilograms in an adult. What are some of the other parts that make up my liver? Thousands of tiny lobules, with blood vessels and bile ducts running between them.

What are the signs of liver problems?

Signs and symptoms of liver disease include tiredness, nausea, itchy skin, yellow skin or eyes, dark urine, pale stools, easy bruising and a swollen belly. What are the 7 signs that my liver is failing? Jaundice, confusion, bleeding easily, vomiting blood, a swollen belly, leg swelling and extreme drowsiness, which need urgent care.

Can a doctor help with liver functions?

Yes. A doctor can look at your symptoms and risks, request a liver function test and explain the results, then look for the cause if something is wrong. A Medio GP can do this by phone, and refer you to a specialist or for a scan if they think you need one.

How can I improve my liver function?

You can improve your liver function by cutting back on alcohol, losing weight if you carry extra, staying active and eating more vegetables and fewer sugary foods. What are other ways to keep your liver healthy? Get vaccinated against hepatitis B, take medicines only as directed, and ask your doctor before starting supplements.

What is the liver function?

The liver function is the work your liver does: making bile to digest fats, processing nutrients, storing energy, making proteins and clearing toxins and medicines. What are the liver's functions on a blood test? A liver function test checks enzymes, bilirubin and proteins to show how well it's coping.

What is the best drink to repair your liver?

No drink repairs the liver on its own. Water is the best everyday drink, and cutting out alcohol does the most to help a damaged liver recover. Some studies link coffee to a lower risk of liver disease, but detox drinks and teas have no proven benefit.