Fatty Liver Blood Test: What 1 in 3 UK Adults Need to Know About Their Liver

Yes, a fatty liver blood test can pick up signs of liver strain years before symptoms appear, and it's more useful than most people realise. Up to 1 in 3 people in the UK have early-stage fatty liver disease, often with zero symptoms, and testing is one of the simplest ways to check, especially during Alcohol Awareness Week, running 6-12 July this year.

Why Liver Health Is Trending in the UK This Week

Alcohol Awareness Week always brings liver health into the conversation, but the story this year is bigger than alcohol alone. Non-alcoholic fatty liver disease, or NAFLD, has actually overtaken alcohol as the leading cause of liver disease in the UK.

That surprises most people I speak with. It's not just heavy drinkers who need to think about their liver. Diet, weight and inactivity all play a role, and around 1 in 5 people in the UK now have NAFLD significant enough to matter clinically.

Alcohol still carries real risk though. Roughly 1 in 5 UK adults drink over the recommended 14 units a week, and alcohol-related liver disease still accounts for over a third of all liver disease deaths. Together, these two causes explain why liver disease deaths in the UK have quadrupled over the last 50 years, now over 11,000 a year.

This year's Alcohol Awareness Week theme from Alcohol Change UK is "Alcohol and Me," and I think that framing is a good one clinically. It asks people to look honestly at their own drinking patterns rather than compare themselves to a stereotype of what "a problem drinker" looks like. Plenty of people who'd never describe themselves that way are still drinking above the 14-unit guideline, and plenty more have liver strain that has nothing to do with alcohol at all. A fatty liver blood test cuts through both of those blind spots.

What Is Fatty Liver Disease?

Fatty liver disease describes a spectrum, not a single fixed condition, and understanding the stages helps explain why early testing matters so much.

It typically starts with fat building up inside liver cells, known as steatosis. On its own, this stage often causes no damage and no symptoms, which is exactly why a fatty liver blood test picks up so many cases that would otherwise go unnoticed.

If fat accumulation continues, it can trigger inflammation, sometimes called steatohepatitis. This is where the liver starts working harder than it should, and where blood markers typically begin to shift.

Left unaddressed, ongoing inflammation can lead to fibrosis, scar tissue forming as the liver tries to repair itself. Early fibrosis often still causes no symptoms, but it's a meaningful turning point clinically.

The most advanced stage is cirrhosis, where scarring becomes extensive and permanent, and the liver's ability to function is seriously compromised. This is exactly why catching fatty liver disease early matters: the earlier stages are far more manageable, and often reversible, than the later ones.

Can you have fatty liver disease without symptoms? 

Yes, and it's the rule rather than the exception. Fatty liver disease is usually symptom-free through its early stages, which is exactly why relying on how you feel isn't a reliable way to rule it out. A liver function blood test is far more useful at this stage than waiting for symptoms to appear.

What a Blood Test Can Actually Tell You

Can a blood test detect fatty liver disease? 

Yes. A liver function blood test can't diagnose fatty liver disease outright, but it can flag raised liver enzymes that suggest something needs a closer look, often years before symptoms start. It's usually the first step, sometimes followed by a scan, to confirm what's actually going on.

Here's the part that matters clinically: liver disease is often silent until it's advanced. Around 4 in 5 people with the more serious form of fatty liver disease are thought to be undiagnosed, simply because there was nothing obvious prompting a test.

A fatty liver blood test checks enzymes and markers that flag when your liver is under strain, often years before any symptoms appear. It's included in our Complete Wellness Check, alongside kidney function, cholesterol and blood sugar, because liver strain rarely shows up in isolation.

If a marker comes back raised, this doesn't confirm liver disease on its own. This is worth discussing with a healthcare professional, who can look at the full picture, including alcohol intake, weight, diet and other blood results, before deciding what happens next.

The best way to catch liver problems early is straightforward, regular testing, not waiting for symptoms like fatigue, itchy skin or abdominal discomfort, which often only appear once damage is more advanced.

Understanding Your Liver Function Test Results

What blood test checks liver function? 

A liver function test, or LFT, is a panel of blood markers rather than a single number. The main ones are ALT, AST, GGT, ALP and bilirubin, and together they build a picture of how your liver is coping.

Reading a liver function test result can feel like decoding another language, so here's what each marker actually means in plain terms.

ALT (alanine aminotransferase) is an enzyme found mainly in liver cells. When liver cells are under strain or damaged, ALT leaks into the bloodstream, so a raised ALT is often the first sign something is worth investigating further.

AST (aspartate aminotransferase) is similar to ALT but is also found in muscle and heart tissue, not just the liver. Looking at ALT and AST together helps clarify whether a raised result is liver-related or coming from somewhere else.

GGT (gamma-glutamyl transferase) is particularly sensitive to alcohol and can rise even before other liver markers do. It's one of the reasons GGT comes up so often in conversations about alcohol and liver health specifically.

ALP (alkaline phosphatase) is found in the liver and in bone, so a raised ALP doesn't automatically point to the liver. Your clinician will usually look at ALP alongside GGT to work out which is more likely responsible.

Bilirubin is a yellow pigment produced when red blood cells break down, and it's processed by the liver. Raised bilirubin can show up as yellowing of the skin or eyes, known as jaundice, and it's a marker of how well the liver is clearing waste products.

None of these markers work well in isolation. This is exactly why a full liver panel, interpreted by a healthcare professional alongside your history and other results, gives a far clearer picture than any single number.

Can Fatty Liver Disease Be Reversed?

Can fatty liver disease be reversed? 

In its earlier stages, yes, often through weight loss, dietary changes and reducing alcohol. Even fibrosis can improve to some degree once the underlying cause is addressed. Cirrhosis, the most advanced stage, is generally not reversible, which is exactly why earlier detection through a fatty liver blood test matters so much.

The most important thing to know about fatty liver disease is that the earlier it's caught, the more control you have over the outcome.

Weight loss is the single most evidence-backed intervention. Losing around 7 to 10% of body weight has been shown to meaningfully reduce liver fat and inflammation, and it doesn't need to happen quickly to be effective.

Regular exercise helps independently of weight loss, improving how the liver handles fat even before the number on the scale changes much.

Reducing alcohol intake matters whether or not alcohol was the original cause, since it adds an extra burden to a liver that's already under strain.

A Mediterranean-style diet, rich in vegetables, olive oil, oily fish and whole grains, and lower in processed and sugary foods, is consistently associated with improved liver health.

Managing type 2 diabetes and prediabetes is closely tied to liver health too, since insulin resistance is one of the main drivers of fat accumulation in the liver. Our GLP-1 Health Monitoring Panel and weight management blood tests are worth considering if this applies to you.

Cholesterol control also plays a role, since raised cholesterol and fatty liver disease frequently occur together and share some of the same underlying drivers.

None of this requires drastic, overnight change. Small, sustained adjustments, tracked with follow-up blood tests, tend to be far more effective than short bursts of extreme effort.

Getting Tested Without the Wait

Liver health isn't always an easy conversation to start with a GP, particularly around alcohol. I understand why many people put it off.

A private blood test UK-wide through Kuon Healthcare removes that barrier. It's a blood test without GP referral, so you can check your liver function on your own terms, privately and without judgement.

Our nationwide blood testing service sends a qualified phlebotomist to your home or workplace, wherever you are in the UK. For a more personal approach, our Bespoke Wellness Profile lets you build a panel around your own history, whether that's alcohol intake, weight changes, family history or simply wanting a baseline.

What We See in Practice

Two misconceptions come up more than any others when I talk to patients about liver health.

The first is that fatty liver disease only affects people who are significantly overweight. In practice, I've seen raised liver markers in people who look outwardly fit and healthy, often linked to diet, insulin resistance or alcohol patterns that don't match the stereotype.

The second is that liver problems always come with warning signs. Most people expect to feel something, tiredness, discomfort, anything, before there's a reason to test. In reality, by the time symptoms appear, the liver has often been under strain for years.

This is exactly why more people are choosing preventative testing over waiting to feel unwell. A baseline liver function blood test gives you a starting point, so any future change can be tracked against your own normal, not a generic range alone.

Who Should Consider a Liver Check

A few patterns come up often in my clinical experience. If any of these apply to you, a liver function blood test is worth considering:

Regularly drinking above 14 units a week, even if it doesn't feel like "a lot." Carrying extra weight, particularly around the middle, or having type 2 diabetes or prediabetes. A family history of liver disease or diabetes. Persistent fatigue, or discomfort in the upper right side of the abdomen. Simply never having had a liver check and wanting a baseline reading.

None of this means something is wrong. It just means testing gives you clarity rather than uncertainty. If several of these apply to you, a broader baseline check, such as our Full Body MOT, can give you a wider picture beyond the liver alone.

Frequently Asked Questions

Can you have fatty liver disease without drinking alcohol? 

Yes. Non-alcoholic fatty liver disease, or NAFLD, is linked to weight, diet and insulin resistance rather than alcohol, and it has overtaken alcohol as the UK's leading cause of liver disease. Up to 1 in 3 UK adults have early-stage NAFLD.

What are the early symptoms of liver problems?

Early liver disease usually has no symptoms at all, which is why it's often caught late. When symptoms do appear, they can include fatigue, discomfort under the right ribs, or itchy skin, but by then the liver is often under significant strain.

What blood test checks liver function?

A liver function test measures enzymes and proteins that indicate how well your liver is working. It's included in our Complete Wellness Check and can also be added to a Bespoke Wellness Profile for a more personalised panel.

How many units of alcohol is safe to drink per week? 

UK guidelines recommend no more than 14 units a week, spread across several days, with some alcohol-free days included. Around 1 in 5 UK adults currently drink above this limit.

Do I need a GP referral to get a liver blood test in the UK? 

No. You can book a private blood test UK-wide through Kuon Healthcare without a GP referral. A phlebotomist visits your home or workplace, and results are reviewed by our clinical team.

Can fatty liver disease be reversed? 

In earlier stages, yes, largely through weight loss, reduced alcohol intake, regular exercise and a healthier diet. Cirrhosis, the most advanced and scarred stage, is generally not reversible, which is why catching things early through a fatty liver blood test matters.

Can you have fatty liver disease with normal liver blood tests? 

Yes, this is possible, particularly in earlier stages, which is why liver blood tests aren't always the final word on their own. If you have risk factors but normal results, this is worth discussing with a healthcare professional, who may suggest imaging or repeat testing.

What causes raised ALT? 

Raised ALT is most commonly linked to fatty liver disease, alcohol, certain medications, or viral hepatitis, though it can also rise temporarily after intense exercise. A raised result on its own isn't a diagnosis, but it is a prompt for further investigation.

What foods are bad for fatty liver? 

Ultra-processed foods, sugary drinks, refined carbohydrates and excess saturated fat are all linked to increased liver fat. A Mediterranean-style diet, built around vegetables, whole grains, olive oil and oily fish, is generally associated with better liver health.

What does GGT mean on a blood test? 

GGT stands for gamma-glutamyl transferase, an enzyme that's particularly sensitive to alcohol intake and can rise before other liver markers change. A raised GGT alongside other liver markers can help build a fuller picture of what's going on, though it isn't diagnostic alone.

Ready to take control of your health? Book your test today at kuonhealthcare.co.uk