Non-alcoholic Fatty Liver Disease: Causes, Diagnosis, and Prevention

You don’t have to be a heavy drinker to have a troubled liver — in fact, your liver might be quietly waving a white flag without you even noticing. Welcome to the sneaky world of Non-alcoholic Fatty Liver Disease (NAFLD) — where sugar, stress, and sofa-time do more damage than a pub crawl ever could.

With about 47 new cases per 1,000 people each year—and higher rates in men– NAFLD is now one of the most common liver conditions worldwide, and the kicker? Most people don’t even know they have it until severe damage is done.

In India, NAFLD is fast turning into a silent epidemic. Studies show that anywhere from nine to 32% of the population may be affected. To put that simply, one to three out of every 10 people could be living with fatty liver disease, often without even knowing it.

The truth is, liver disease isn’t something to take lightly. But the good news? Your everyday habits—what you eat, how active you are, how you manage your weight—play a big role in prevention and recovery.

Let’s break it down and see what you can do to protect your liver health.

Non-alcoholic Fatty Liver Disease—now also known as Metabolic dysfunction-associated steatotic liver disease (MASLD)—is when fat builds up in your liver, and it’s not because of drinking excessive alcohol.

This usually happens when your body is dealing with things like being overweight, high blood sugar, high cholesterol, or high blood pressure. Basically, your liver starts storing fat it shouldn’t.

What is Fatty Liver?

Let’s break it down. Your liver is the largest organ inside your body. It helps you digest food, store energy, and filter out harmful stuff.

It’s completely normal for your liver to have a little bit of fat. But when that fat makes up more than five to 10% of your liver’s weight, that’s when it’s called fatty liver, or steatosis.

Think of it like this: your liver’s supposed to help your body run smoothly, not store excess fat like a pantry.

We still don’t know the exact cause of NAFLD (or MASLD), but what we do know is that certain health conditions can increase your chances of developing it. Things like obesity, insulin resistance, type 2 diabetes, and high levels of cholesterol or triglycerides are often behind it.

Who’s at risk?

While NAFLD can affect anyone, including children and teens, it’s most commonly seen in middle-aged adults. Here are some key risk factors to watch out for :

• Carrying excess weight, especially around your belly

• Having type 2 diabetes

• High blood pressure

• High cholesterol

• Metabolic syndrome (a combo of diabetes, high blood pressure, and obesity)

• High triglyceride levels in your blood

• Being over the age of 50

• Smoking

• Insulin resistance

• PCOS (polycystic ovary syndrome)

• Sleep apnea

• Hypothyroidism (underactive thyroid)

If any of these sound familiar, it’s a good idea to monitor your liver health and check in with your doctor regularly.

In its early stages, NAFLD usually doesn’t cause much trouble, but if it’s left unchecked, it can lead to serious liver damage over time. The good news? For most people, it stays mild. But in some cases, it can progress through several stages.

Let’s break down the four main stages of NAFLD :

1. Simple Fatty Liver (Steatosis)

This is the earliest stage. It’s just a build-up of fat in the liver and usually doesn’t cause any harm. Most people don’t even know they have it—it's often found by chance during tests for something else.

2. Non-Alcoholic Steatohepatitis (NASH)

Now things get more serious. At this stage, the liver becomes inflamed, which means the body is reacting to the fat build-up. Inflammation can lead to damage if not managed.

3. Fibrosis

With ongoing inflammation, scar tissue forms around the liver and nearby blood vessels. The liver still works fairly well at this point, but the damage is starting to add up.

4. Cirrhosis

This is the most advanced and serious stage. Over time, scarring becomes severe, the liver shrinks, and its texture becomes lumpy and hardened. This stage is permanent and can lead to liver failure or even liver cancer.

Here’s the good news - It can take years to move from one stage to the next. And if NAFLD is caught early, making healthy lifestyle changes—like improving your diet, staying active, and losing weight—can slow it down or even reverse it in the early stages.

So yes, your liver is resilient—but it needs your help to stay that way.

Fatty liver is often called a “silent killer”—and for good reason. In the early stages, NAFLD usually doesn’t show any obvious symptoms, which means many people don’t even know they have it.

But when symptoms do appear, here’s what you might notice:

• A general feeling of being unwell (malaise)

• Discomfort or mild pain in the upper right side of the belly

• Fatigue or feeling tired all the time

If it progresses to NASH (a more advanced stage), symptoms can get more noticeable and serious:

• Severe fatigue that doesn’t go away

• Pain or pressure in the upper right abdomen

• Weakness

• Unexplained weight loss

• Yellowing of the skin or eyes (jaundice)

• Spider-like blood vessels visible on the skin

• Itchy skin

• Redness in the palms

• Shortness of breath

Since symptoms can be vague or even absent, regular checkups and blood tests are key—especially if you have risk factors like obesity or diabetes. Catching it early can make all the difference.

The biggest complication of NAFLD—especially when it progresses to NASH—is cirrhosis, which is severe scarring of the liver. This happens when long-term inflammation damages liver tissue, and the liver tries to heal itself by creating scar tissue (called fibrosis).

Over time, this scarring builds up, hardens the liver, and reduces its ability to function. When it becomes widespread and permanent, it’s called cirrhosis—and that’s when things can get serious.

What can cirrhosis lead to?

If left untreated, cirrhosis can cause:

• Fluid buildup in the belly (ascites)

• Swollen veins in the esophagus, which can rupture and bleed

• Mental confusion, drowsiness, and slurred speech (due to toxin buildup in the brain)

• An overactive spleen, which can lead to low blood cell counts

• Liver cancer

• End-stage liver failure—where the liver can no longer do its job

The scary part? These complications are often irreversible. But the good news is, early intervention—through lifestyle changes and medical support—can stop the disease from progressing this far.

Your liver’s tough, but it can’t do it alone.

You might have NAFLD and not even know it, because it often shows no symptoms at all. In fact, many people only find out they have it during a routine blood test that picks up abnormal liver function. To confirm what's going on, your doctor may recommend a few tests:

How NAFLD is diagnosed :

• Blood tests – to check how your liver is functioning

• Imaging tests – like an ultrasound, CT scan, or MRI, to look for fat in the liver

• Liver biopsy – In some cases, a small sample of liver tissue may be taken to check for inflammation or scarring

What your results could mean :

• If you have fat in your liver but no inflammation or damage, you likely have MASLD (Metabolic dysfunction-associated steatotic liver disease, formerly NAFLD).

• If there’s fat, inflammation, and liver cell damage, that’s called MASH (Metabolic dysfunction-associated steatohepatitis, formerly NASH).

• If tests show scar tissue (fibrosis), you may be developing cirrhosis, which is a more advanced stage of liver damage.

There’s no specific medication approved just for NAFLD yet—but the best ‘treatment’ often starts with lifestyle changes. Things like eating healthier, exercising regularly, managing weight, and keeping blood sugar and cholesterol in check can go a long way in reversing or slowing the disease.

Not all is lost. It turns out, like so many other diseases and conditions, this too can be controlled or reversed by making some lifestyle changes. There are things that you can do to reduce your risk of NAFLD :

• Eating a healthy diet - Try to incorporate a diet rich in fruits, vegetables, lean proteins, healthy fats and whole grains, but low in sugar and salt. Avoid sugary drinks and processed food. Also, be mindful of your portion size.

• Losing weight - If you are overweight or obese, try to make changes to your lifestyle and routine.

Here’s the good news: NAFLD isn’t a life sentence. Just like many other lifestyle-related conditions, it can often be prevented—and even reversed—with a few smart changes to your daily routine.

Here’s what you can do to lower your risk and keep your liver healthy:

1. Eat a balanced, healthy diet

• Fill your plate with fruits, vegetables, whole grains, lean proteins, and healthy fats.

• Cut back on sugar, salt, processed foods, and sugary drinks.

• Also, keep an eye on portion sizes—eating too much of even healthy food can still lead to weight gain.

2. Lose extra weight

If you're overweight or obese, slow and steady weight loss can help reduce liver fat and inflammation. Even losing five to 10% of your body weight can make a big difference.

3. Get moving

Physical activity is a game-changer. Whether it's a walk, dancing, swimming, hitting the gym, or yoga, just move. Aim for at least 30 minutes of activity most days of the week. Move. It’s good for you!

4. Limit or avoid alcohol

NAFLD isn’t caused by alcohol, but drinking can definitely make it worse. If possible, avoid alcohol altogether, or at least limit your intake to protect your liver from added stress.

Remember, small changes can lead to big improvements over time. Your liver works hard for you—show it some love back!

Taking care of your liver doesn’t have to be complicated. You can prevent or even reverse fatty liver with a few healthy habits and regular checkups. Start small, stay consistent—and your liver will take care of the rest!