Your liver can be damaged for years without obvious warning signs. Most liver problems develop silently, and by the time symptoms appear, the disease may already be moderately advanced. The most reliable way to check your liver health is through a simple blood test called a liver function panel, which your doctor can order as part of routine bloodwork. But there are also physical signs worth paying attention to, and certain risk factors that mean you should be screened proactively.
Why Liver Problems Are Easy to Miss
The liver is remarkably resilient. It can keep functioning even when a significant portion of it is inflamed or scarred, which means you can feel perfectly fine while damage accumulates. Fatty liver disease alone now affects roughly 1.3 billion people worldwide, about 16% of the global population. Most of those people have no idea anything is wrong.
This is why waiting for symptoms is not a good strategy. If you’re wondering whether your liver is OK, the honest answer is: you probably can’t tell just by how you feel. You need data.
Physical Signs That Suggest a Problem
When the liver does start sending signals, they tend to show up in ways you might not immediately connect to your liver. The classic signs include:
- Yellowing of the skin or whites of the eyes (jaundice). This happens when your liver can’t clear bilirubin, a waste product from broken-down red blood cells. On darker skin tones, jaundice may be easier to spot in the eyes or on the palms.
- Dark urine or pale, clay-colored stool. Both point to bilirubin not being processed normally.
- Swelling in the belly, legs, or ankles. A struggling liver can’t produce enough albumin, a protein that keeps fluid in your blood vessels. Without it, fluid leaks into surrounding tissue.
- Itchy skin. Bile salts that the liver normally clears can build up and deposit under the skin.
- Easy bruising. Your liver makes clotting proteins. When it’s impaired, even minor bumps leave marks.
- Persistent fatigue, nausea, or loss of appetite. These are vague but common early complaints.
None of these symptoms are unique to liver disease, which is part of the problem. Fatigue and nausea have a hundred possible causes. But if you’re experiencing several of these together, especially jaundice or unexplained swelling, that warrants prompt medical attention.
The Blood Test That Checks Your Liver
A liver function panel is a standard blood draw that measures several markers at once. It’s inexpensive, widely available, and often included in routine checkups if you ask for it. Here’s what it measures and what each marker tells you:
ALT and AST are enzymes concentrated in liver cells. When liver cells are damaged or inflamed, these enzymes spill into your bloodstream. Normal ALT runs between 7 and 55 units per liter; normal AST is 8 to 48. Elevated levels suggest your liver is under stress, though the numbers alone don’t tell you why.
Albumin is a protein your liver manufactures. A healthy range is 3.5 to 5.0 grams per deciliter. Low albumin can indicate that your liver’s ability to produce essential proteins has declined, which typically happens with more advanced disease.
Bilirubin is the waste product that causes jaundice when it builds up. Normal levels fall between 0.1 and 1.2 milligrams per deciliter. Elevated bilirubin means your liver isn’t clearing waste efficiently.
The panel also checks alkaline phosphatase (ALP), which rises when bile ducts are blocked or inflamed, and prothrombin time, which measures how quickly your blood clots. Slow clotting can signal that your liver isn’t making enough clotting proteins. These reference ranges can vary slightly between labs and may differ for women and children, so your results will come with the specific lab’s normal range printed alongside your numbers.
When Elevated Numbers Don’t Mean Liver Disease
An abnormal result on a liver panel doesn’t automatically mean your liver is sick. ALT and AST can spike temporarily from things that have nothing to do with chronic liver damage. Common culprits include over-the-counter pain relievers like acetaminophen (Tylenol), cholesterol-lowering medications called statins, intense exercise, and even herbal supplements. Alcohol consumed in the days before a blood draw can also push numbers up.
If your results come back slightly elevated, your doctor will typically repeat the test after a few weeks to see whether the spike was temporary. Persistently elevated enzymes, especially ALT, are what raise real concern and usually trigger further investigation.
Risk Factors That Warrant Proactive Screening
Certain people should be checked even if they feel fine. Current clinical guidelines recommend proactive liver screening for anyone with type 2 diabetes, anyone with two or more metabolic risk factors, and anyone who’s had an incidental finding of fatty liver or elevated enzymes on prior bloodwork.
The metabolic risk factors that matter most are the ones tied to fatty liver disease, now officially called metabolic dysfunction-associated steatotic liver disease (MASLD). You may have heard it called NAFLD or “non-alcoholic fatty liver disease,” but the medical community updated the name in 2023 to better reflect what drives the condition. You’re at risk if you have any one of the following: a BMI of 25 or higher, fasting blood sugar of 100 mg/dL or above (or a diabetes diagnosis), blood pressure at or above 130/85, triglycerides of 150 mg/dL or higher, or low HDL cholesterol (below 40 for men, below 50 for women).
Alcohol use is also assessed during screening. A newer category called MetALD describes people who have fatty liver disease and also drink moderate-to-heavy amounts of alcohol, recognizing that metabolic factors and alcohol can compound each other’s damage.
Imaging Tests That Go Deeper
If bloodwork suggests a problem, the next step is usually an imaging test to look at the liver directly. A standard abdominal ultrasound can reveal fat deposits and structural changes, and it’s painless and quick.
For a more precise picture, especially of scarring (fibrosis), doctors use a technique called elastography. This works like an ultrasound but measures how stiff your liver tissue is. Healthy liver is soft; scarred liver is stiff. Ultrasound elastography, sometimes called FibroScan, is the most common version and is about as accurate as a traditional biopsy for diagnosing fibrosis, without requiring a needle. MRI-based elastography provides even more detail and is typically reserved for cases where more extensive damage is suspected or when a patient’s body size makes ultrasound less effective.
Liver biopsy, where a small tissue sample is taken with a needle, used to be the gold standard but is now less common as a first-line test thanks to these non-invasive alternatives.
What You Can Do Right Now
If you haven’t had bloodwork recently, request a liver function panel at your next appointment. It’s a reasonable ask for any adult, and it’s especially important if you carry excess weight, have diabetes or prediabetes, take regular medications (particularly acetaminophen or statins), or drink alcohol regularly.
In the meantime, the lifestyle factors that protect your liver are straightforward. Reducing alcohol intake has the most direct impact. Losing even 5 to 10% of your body weight can measurably reduce liver fat in people with fatty liver disease. Regular physical activity helps independent of weight loss. And being cautious with acetaminophen, which is processed entirely by the liver, matters more than most people realize. Staying within the recommended dose and avoiding it when you’re drinking alcohol are simple steps that prevent a surprising amount of liver injury.
Your liver is likely fine if your bloodwork is normal, you don’t have major risk factors, and you’re not experiencing any of the symptoms listed above. But “likely fine” and “confirmed fine” are different things, and confirmation only takes a single blood draw.