Fatty Liver Disease
Key points
- About 1 in every 3 Australian adults has fatty liver disease
- It means too much fat has built up in the liver
- Fatty liver can be caused by problems with how your liver processes what you eat and drink (your metabolism), too much alcohol, a virus infection, some medicines and some other health conditions
- Over time, fatty liver can lead to liver damage
- Liver damage can gradually get worse and cause serious problems like cirrhosis, liver failure, liver cancer, and heart problems
- For most people, liver damage can be reversed
- Following a healthy lifestyle can make your liver as healthy as possible and is also good for your overall health
What is fatty liver disease?
Fatty liver disease is when fat builds up in the liver’s cells. It’s normal for all livers to contain some fat. But when fat makes up more than 5 to 10% of the total weight of the liver, it’s called fatty liver.
Anyone can develop a fatty liver. It can be caused by drinking too much alcohol, having overweight or obesity, having a condition like diabetes or polycystic ovary syndrome (PCOS), an underactive thyroid, or as a reaction to some medicines.
Here are the main causes of fatty liver disease:
Metabolic Associated Fatty Liver Disease (MAFLD): the most common type of fatty liver disease is caused by having overweight or obesity or not being active enough. People who have obesity, type 2 diabetes, high blood pressure and high cholesterol are at particular risk of fatty liver disease – even if they don’t realise it yet. The biggest risk factor for obesity that leads to fatty liver is having a diet high in sugars, saturated fats and processed foods.
Alcohol-related fatty liver disease: Most people know alcohol is bad for the liver. You’re at risk of fatty liver disease related to alcohol if you drink more than 10 standard drinks each week or if you binge drink (more than 4 standard drinks in a day).
Read more about alcohol and the liver
In many people, fatty liver is caused by many things at the same time, including a poor diet, being overweight, having diabetes and drinking too much alcohol.
The more causes you have, the faster the fatty liver is likely to get worse and the worse the outcome is likely to be.
What is Metabolic Associated Fatty Liver Disease (MAFLD)?
MAFLD is a type of fatty liver disease caused by problems of the metabolism. The metabolism is how your body makes energy to grow, reproduce, stay healthy and get rid of toxins.
More people these days have problems with their metabolism caused by having overweight or obesity, a poor diet and not getting enough physical activity. You may have metabolic problems if you have:
- a large waist size
- high amount of ‘bad’ cholesterol (LDL)
- low ‘good’ cholesterol (HDL)
- high blood pressure
- high blood sugar or diabetes
People who have 3 or more of these conditions have what’s known as metabolic syndrome. They may be quite overweight or carry a lot of weight around their middle. Some people with metabolic syndrome aren’t overweight at all – their fat is all deep inside their body.
Metabolic syndrome is very common. It can lead to serious conditions including type 2 diabetes and heart problems. It can also lead to MAFLD.
MAFLD is the most common cause of chronic liver disease in the world. In Australia, more than a third of people (37%) are thought to have the condition. People with MAFLD are also likely to have other health problems caused by their poor metabolism, such as heart disease, high blood pressure or type 2 diabetes.
MAFLD used to be called Non-Alcoholic Fatty Liver Disease (NAFLD). It is possible to get liver disease from both drinking an unhealthy amount of alcohol and being overweight or obese. You can have both conditions, and both need to managed to prevent complications.
If you have MAFLD, you are also at increased risk of cardiovascular problems like a heart attack or stroke. You are also at increased risk of many cancers. Changing your diet, reducing your weight, getting more exercise and sitting less will help reduce the risk.
What are the symptoms of fatty liver disease?
Fatty liver disease usually has no symptoms at all. Most people are diagnosed when they have a blood test or ultrasound for something else.
If you do develop symptoms, they might include feeling generally quite tired, and having some pain in the upper right side of the trunk.
Some signs that you have more serious liver disease are:
- Yellow eyes and skin (jaundice)
- Bruising easily
- Dark urine
- Swollen belly (asites)
- Vomiting blood
- Black poos
- Itchy skin
If you have any of these symptoms, see your doctor.
Fatty liver disease isn’t necessarily harmful at first. But it’s a progressive disease. That means it gets worse slowly over time. It causes inflammation in the liver, which eventually leads to scarring (fibrosis) and sometimes damage to the liver function (cirrhosis) or liver cancer. This more advanced stage of the disease is called non-alcoholic steatohepatitis (NASH).
Most people with fatty liver disease don’t get cirrhosis or NASH. But they are still at increased risk of heart disease, diabetes, kidney disease and cancer.
Read more about the symptoms of liver diseaseHow is fatty liver disease diagnosed?
If your doctor is worried about your liver, they may request a blood test to see how well your liver is functioning.
Liver function blood tests look for abnormal levels of liver enzymes in your blood. If you have fatty liver disease, you may have raised levels of the liver enzymes aspartate transaminase (AST), alanine transaminase (ALT) and gamma-glutamyl transpeptidase (GGT). If you have advanced liver disease and cirrhosis, you may have a reduced platelet count and albumin levels.
If you have fatty liver disease, your doctor will then try to work out how much scarring (fibrosis) there is in your liver. This may be done through a blood test, with an ultrasound or FibroScan. Some people need a biopsy, when a small piece of tissue is removed from the liver to be examined under a microscope.
Read more about liver testsWhy did I get fatty liver disease?
The liver is responsible for breaking down fats and sugars from our food. When we consume more fat and sugar than our body needs, it’s stored as fat.
Most cases of fatty liver disease are caused by having overweight or obesity. But some people develop fatty liver disease even if they are a healthy weight.
You are more likely to get fatty liver disease if you:
- are above the recommended Body Mass Index
- have a high waist measurement
- have insulin resistance or type 2 diabetes
- have high levels of cholesterol in your blood
- have high blood pressure
- consume a lot of fatty foods, sugary drinks or highly processed food
- don’t get much exercise (you are sedentary)
How is fatty liver disease treated?
There is no medication that can treat fatty liver disease. But there are more than 200 drug trials around the world looking for a new medication and some of these are very promising.
In the meantime, you can stop it getting worse or even reverse the liver damage:
- Eat a healthy diet
- Do more physical activity
- Lose weight if you need to
- If you have diabetes, talk to your doctor about getting it under control
- If you have high cholesterol, talk to your doctor about getting it under control
- Avoid alcohol and smoking
Doing these things will reduce fat and inflammation in the liver. Losing 5 to 10% of your weight can control and sometimes even reverse fatty liver disease.
If you have early-stage disease, your doctor will monitor you and check your liver every few years. They will help you look after your liver health and hopefully repair or reverse the condition. They will want to check for scarring (fibrosis) every few years, and will keep an eye on your weight and BMI, blood sugars, blood fats and blood pressure.
People with more advanced disease, NASH, need to see a specialist liver doctor (hepatologist or gastroenterologist). As well as looking after their liver health, they will need regular scans to monitor their condition and check for liver cancer. Some people might be offered an opportunity to participate in a clinical trial.
It’s not possible to predict which people with fatty liver disease are going to go on to develop more advanced disease.
Read more about liver treatmentsFatty liver disease in children
As more children in Australia develop overweight and obesity, they are also developing fatty liver disease. In fact, the condition has been found in children as young as 2.
It’s thought that fatty liver disease in children is related to what they eat (too much fat and sugar in their diet) and not enough physical activity. But it can also be caused by other problems with the metabolism such as Wilson’s disease, viral hepatitis, or an autoimmune diseases.
Living with fatty liver disease
If you have fatty liver disease, it’s important for your overall health to follow a healthy lifestyle. Even small changes can make a big difference.
Your doctor will talk to you about medicines you might be taking for other conditions. If your liver isn’t working properly, you may need to avoid some certain medicines.
Keep an eye on your blood pressure and blood sugar, and make sure you keep regular appointments with your GP. It is important that conditions such as diabetes, high blood pressure and high cholesterol are treated well and regularly monitored. You probably won’t need to see a liver specialist unless your disease gets worse.
Read about lifestyle tipsWhat next?
Read more about living wellReferences
American Liver Foundation. Nonalcoholic Fatty Liver Disease (NAFLD).
British Liver Trust. NAFLD, NASH and fatty liver disease.
Brunt EM, Wong VW, Nobili V, Day CP, Sookoian S, Maher JJ, Bugianesi E, Sirlin CB, Neuschwander-Tetri BA, Rinella ME. Nonalcoholic fatty liver disease. Nat Rev Dis Primers. 2015 Dec 17;1:15080. doi: 10.1038/nrdp.2015.80. PMID: 27188459.
Canadian Liver Foundation. Fatty liver disease
Eslam M et al. Hepatol Int 2020;14:889–919. 2. Pardo Lameda IL,. Koch TR. (2020). Chapter 10: Acquired Metabolic Disorders. In: Radu-Ionita F et al. (eds). Liver diseases: a multidisciplinary textbook. Springer International Publishing, Cham, pp 107–116.
Farrell AM, Magliano DJ, Shaw JE, Thompson AJ, Croagh C, Ryan MC, Howell J. A problem of proportions: estimates of metabolic associated fatty liver disease and liver fibrosis in Australian adults in the nationwide 2012 AusDiab Study. Sci Rep. 2022 Feb 4;12(1):1956. doi: 10.1038/s41598-022-05168-0. PMID: 35121749; PMCID: PMC8817026.
Gofton C, George J. Updates in fatty liver disease: Pathophysiology, diagnosis and management. Aust J Gen Pract. 2021 Oct;50(10):702-707. doi: 10.31128/AJGP-05-21-5974. PMID: 34590082.
Health Direct. Body mass index (BMI) and waist circumference
Iser D, Ryan M. Fatty liver disease–a practical guide for GPs. Aust Fam Physician. 2013 Jul;42(7):444-7. PMID: 23826593.
Mayo Clinic. Nonalcoholic fatty liver disease
MedlinePlus. Fatty Liver Disease.
The Westmead Institute for Medical Research. MAFLD: A new name and definition brings hope for patients with fatty liver disease
Reviewed November 2022