- Fatty liver affects about 30% of adults worldwide, and most of them feel completely well.
- When early symptoms appear, they are vague: tiredness and a dull ache or fullness under the right ribs.
- Yellow eyes, a swollen belly, vomiting blood or new confusion are signs of advanced disease and need urgent care.
- People with type 2 diabetes, obesity or metabolic syndrome should ask about a simple liver check, even without symptoms.
Your liver is a quiet organ. It has no pain nerves inside it, and it keeps doing its hundreds of jobs even when a large part of it is under strain. That is good news for survival, but it means fat can build up in the liver for years without a single warning sign. Most people find out by chance, after a routine blood test or an ultrasound done for another reason.
Doctors now call this condition metabolic dysfunction-associated steatotic liver disease (MASLD). When the fat is joined by inflammation and liver cell damage, it is called MASH. You may still see the older names, NAFLD and NASH, on reports and websites; they describe largely the same people. If you are new to the topic, start with our overview, Fatty Liver (MASLD) Explained. This article goes deeper into symptoms: what you might notice, what you probably will not, and when to act.
How common is a “silent” fatty liver?
Younossi et al., Hepatology 2023 (meta-analysis); Younossi et al., J Hepatol 2019 (people with type 2 diabetes).
With numbers like these, fatty liver is one of the most common health conditions on earth. Yet many people who have it do not know. The reason is simple: in its early stages, it rarely causes symptoms at all.
Early symptoms: subtle, if any
Some people with MASLD or MASH do notice changes. None of them is specific to the liver, so they are easy to put down to a busy life, poor sleep or getting older.
The most commonly reported symptom. It can have many causes, including poor sleep, low iron or thyroid problems.
A dull ache, heaviness or fullness under the right ribs, sometimes from a slightly enlarged liver stretching its outer capsule.
Velvety darkening on the neck or armpits (acanthosis nigricans) is a sign of insulin resistance, which often travels with fatty liver.
Not a symptom of the liver itself, but belly fat is one of the strongest clues. See visceral fat and metabolic health.
Importantly, how you feel says very little about how much damage there is. People with significant scarring can feel fine, and people with only mild fat can feel tired for unrelated reasons. That is why testing, not symptoms, guides decisions.
Why symptoms come so late
Fatty liver usually moves slowly, over years or decades, and many people never progress beyond simple fat. When it does progress, it follows a familiar path. The liver has huge spare capacity, so it keeps working normally until scarring is advanced.
How fatty liver can progress, and where symptoms usually start
Rinella et al., multisociety nomenclature consensus, Hepatology 2023. Fat and early scarring can often improve with lifestyle changes.
The stage that matters most for long-term health is fibrosis, the amount of scar tissue. Large studies show that the risk of serious liver problems rises sharply as fibrosis advances, while fat alone carries a much lower risk. It is also worth knowing that the most common cause of death in people with MASLD is heart disease, not liver failure, because the same metabolic problems affect both organs.
Signs of advanced liver disease
When scarring becomes severe (cirrhosis), the liver starts to struggle with its jobs: clearing toxins, making proteins and clotting factors, and letting blood flow through easily. That is when clearer signs appear.
- Yellow skin or yellow whites of the eyes (jaundice)
- Swollen belly (fluid, called ascites) or swollen ankles and legs
- Bruising or bleeding easily, including nosebleeds
- Confusion, drowsiness or unusual forgetfulness
- Itchy skin, dark urine or pale stools
- Unplanned weight loss and muscle wasting
- Sharp or stabbing pain under the ribs (gallstones are common)
- Burning in the chest or upper belly after meals (reflux)
- Bloating and gas
- Headaches
Get urgent medical help (emergency department or emergency number) if you vomit blood or material that looks like coffee grounds, pass black tarry stools, become confused or very drowsy, or develop yellow eyes with a fever or a rapidly swelling belly. These can be signs of serious liver complications that need same-day treatment. For new yellowing of the skin or eyes without these, see a doctor within a day or two.
Who should get checked, even without symptoms
Because symptoms are unreliable, major liver and diabetes societies recommend looking for fatty liver and scarring in people at higher risk. The good news is that the first step is simple: a routine blood test that your doctor can turn into a scarring score called FIB-4.
- Type 2 diabetes or prediabetes. This is the single biggest risk group for scarring.
- Obesity or a large waist, especially with high blood pressure, high triglycerides or low HDL.
- Metabolic syndrome: three or more of the five metabolic syndrome numbers outside the healthy range.
- Raised liver enzymes (ALT or AST) on any blood test, or fat seen on an ultrasound done for another reason.
- A close relative with cirrhosis, or regular alcohol use on top of metabolic risk factors.
People of South Asian heritage deserve special mention. Fatty liver and insulin resistance are common at lower body weights in South Asians, so a “normal” BMI does not rule it out. We explain why in What Causes Fatty Liver?
Check your waist. Waist size is a better clue to liver fat than weight alone. Try our Waist-to-Height Ratio Calculator; a ratio above 0.5 is a good reason to ask your doctor about your liver.
What to ask your doctor
If you fit one of the groups above, you do not need to wait for symptoms. At your next visit, ask whether your recent blood tests can be used to work out your FIB-4 score, and whether you need a liver scan. Bring a list of all medicines and supplements, and be honest about how much alcohol you drink, because both change how results are read. The tests themselves are covered in Fatty Liver Tests: Liver Enzymes, FIB-4 and Scans Explained.
MythIf your liver was in trouble, you would feel it.
FactThe liver has no internal pain nerves and huge reserve capacity. Most people with fatty liver, and many with significant scarring, feel perfectly well.
Common questions
Can fatty liver cause pain on the right side?
Sometimes. A dull ache or fullness under the right ribs can happen when the liver is enlarged. Sharp, severe or constant pain is more likely to be something else, such as gallstones, and should be checked.
Can fatty liver make me tired?
It can, and tiredness is the most common complaint. But fatigue has many causes, including poor sleep, sleep apnea, low iron, low vitamin B12 and thyroid problems, so it is worth a general check-up.
If my liver enzymes are normal, can I still have fatty liver?
Yes. Many people with fatty liver, and some with scarring, have normal ALT. That is why doctors use scores like FIB-4 and scans rather than enzymes alone.
Are skin changes a sign of fatty liver?
Dark, velvety patches on the neck or armpits point to insulin resistance rather than the liver itself. Yellow skin or eyes is different and needs prompt medical attention.
- About 3 in 10 adults have fatty liver, and most have no symptoms at all.
- Early clues are vague: tiredness and a dull ache under the right ribs.
- Jaundice, a swollen belly, easy bleeding, black stools or confusion signal advanced disease and need urgent care.
- If you have type 2 diabetes, obesity or metabolic syndrome, ask for a FIB-4 check rather than waiting for symptoms.
- Next: What Causes Fatty Liver? The Main Drivers.
Sources
- Rinella ME, Lazarus JV, Ratziu V, et al. A multisociety Delphi consensus statement on new fatty liver disease nomenclature. Hepatology. 2023;78(6):1966–1986.
- Younossi ZM, Golabi P, Paik JM, et al. The global epidemiology of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH): a systematic review. Hepatology. 2023;77(4):1335–1347.
- Younossi ZM, Golabi P, de Avila L, et al. The global epidemiology of NAFLD and NASH in patients with type 2 diabetes: a systematic review and meta-analysis. J Hepatol. 2019;71(4):793–801.
- Rinella ME, Neuschwander-Tetri BA, Siddiqui MS, et al. AASLD Practice Guidance on the clinical assessment and management of nonalcoholic fatty liver disease. Hepatology. 2023;77(5):1797–1835.
- European Association for the Study of the Liver (EASL), European Association for the Study of Diabetes (EASD), European Association for the Study of Obesity (EASO). EASL-EASD-EASO Clinical Practice Guidelines on the management of metabolic dysfunction-associated steatotic liver disease (MASLD). J Hepatol. 2024;81(3):492–542.
- Dulai PS, Singh S, Patel J, et al. Increased risk of mortality by fibrosis stage in nonalcoholic fatty liver disease: systematic review and meta-analysis. Hepatology. 2017;65(5):1557–1565.
This article is for general education and is not a substitute for advice from your own doctor or healthcare team.