The causes of fatty liver disease, plus how it can be treated and possibly reversed

The liver works hard and performs a ton of important functions for the human body. From aiding in digestion to cleaning your blood, it helps keep your body going, so you want to keep it as healthy as possible. With fatty liver disease, now more commonly called metabolic dysfunction-associated steatotic liver disease (MASLD), the liver can become damaged, disrupting its hard work.

It is as it sounds – it means there is excess fat in the liver, and it’s causing health problems. Without treatment, the presence of fat in the liver can lead to serious health risks.

Fortunately, MASLD is preventable and can be reversed with lifestyle changes and weight loss. Here, we’ll go into what different types of liver diseases are where fat is present, and what can cause them. We’ll also go over who is more at risk of developing it, and treatments that can help stop and possibly reverse damage to the liver.

What are MASLD, MASH and ALD (fatty liver diseases), and what can cause them?

Typically, a healthy, well-functioning liver contains a small amount of fat, which shouldn’t cause you to experience any symptoms. But if that percentage of fat becomes too high, it can cause liver damage and lead to serious complications. MASLD, MASH and ALD can happen for a number of reasons, but there are certain groups who are more at risk of developing it.

Metabolic dysfunction associated steatotic liver disease (MASLD)

Previously known as non-alcoholic fatty liver disease (NAFLD), this is the most common type of metabolic liver disease in the U.S. and affects about one in three adults. It’s not known what exactly causes it, but certain health conditions like diabetes and obesity can increase your risk of developing it. Most people diagnosed with MASLD have what clinicians call hepatic steatosis, an early phase where there is fat present in the liver but it hasn’t built up and reached the inflammatory stage.

Metabolic dysfunction-associated steatohepatitis (MASH)

MASH is a more severe form of liver disease that is caused by a buildup of fat in the liver and affects 1.5-6.5% of the U.S. population. Formerly known as non-alcoholic steatohepatitis (NASH), this is where inflammation in the liver can cause scarring, and in turn, more serious health problems, like cirrhosis. It’s important to note as well that chronic liver inflammation alone can cause liver cancer, so it’s important to address symptoms before MASH can become more serious.

The differences between MASLD and MASH

While both MASLD and MASH occur due to the presence of fat in the liver, there are differences between the two. MASLD is a form of liver disease that is diagnosed earlier on, and MASH is what MASLD can progress to over time, especially if it goes untreated.

With MASLD, treatment should begin as early as possible, as it’s possible to slow and stop the progression of the disease before MASH occurs. If left untreated, serious complications can develop.

Alcohol-related steatotic liver disease (ALD)

ALD is also a buildup of fat in the liver that’s caused by heavy alcohol use. Heavy alcohol use for men is considered five or more alcoholic drinks per day, or 15 or more drinks per week. For women, excessive alcohol use is considered consuming four or more drinks per day, or eight or more drinks per week.

Like with MASLD and MASH, there are often no symptoms associated with ALD, and not everyone who drinks alcohol experiences it. Studies show that there may be a genetic link to developing it, but the exact cause isn’t known. ALD is very common and very preventable, but it can progress to cause serious health problems, like cirrhosis, if not treated.

What is MetALD?

Previously, steatotic liver diseases not caused by alcohol and ALD were seen as completely separate conditions and were treated as such. But there’s a new category that has been created to cover people with metabolic liver disease who also drink moderate amounts of alcohol, named MetALD. The reason for adding this category is to bridge the gap between MASLD and alcohol-related liver diseases when it comes to treatment and clinical trials.

While there are medications and clinical trials that have helped people with MASLD and MASH, not a lot of research has been done for people with ALD and MetALD. However, research has shown that the medications and treatments that have helped symptoms in people with non-alcohol related metabolic diseases can also help with symptoms of ALD, as well as help someone with ALD reduce alcohol consumption.

With this new category, scientists have been able to better research the impact alcohol use has on liver diseases. It also acknowledges the coexistence of metabolic risk factors and alcohol use, and puts steatotic liver diseases on a spectrum, rather than defining them as separate conditions.

When fat in the liver can become a problem

Fat in the liver that hasn’t caused symptoms can become a problem easily, especially if measures aren’t taken to treat it, like lifestyle changes and weight loss. If left untreated, liver disease can progress in stages:

• Hepatitis –  Fat in the liver can cause inflammation.
• Fibrosis –  If inflammation isn’t treated, it can cause scarring of the liver.
• Cirrhosis –  Scarring on the liver can cause it to work improperly or stop working at all.
• Liver failure –  This can include a swollen liver, internal bleeding and other problems, and can only be cured by a liver transplant.

Who’s more at risk of developing MASLD and MASH (fatty liver disease)?

Steatotic liver diseases have historically been more common in older adults, but MASH has become the leading cause of liver disease in children. There are certain health conditions and risk factors that may increase your chance of developing it, including:

• A family history of steatotic liver disease
• Being overweight or obese with fat concentrated around the waist
• Having Type 2 diabetes or being diagnosed as prediabetic
• Having high levels of fat, like high triglycerides and high levels of LDL (“bad”) cholesterol, or having low levels of HDL (“good”) cholesterol in your blood
• Being diagnosed with a metabolic syndrome, where you may have high blood pressure, high blood sugar and other conditions
• Having sleep apnea
• If you’re postmenopausal
• Consuming large quantities of alcohol for long periods of time can increase your chances of developing ALD

There are other reasons you may develop MASLD and MASH, like if you take certain medications or if you have polycystic ovary syndrome (PCOS), but they’re less common.

Because there are often no symptoms associated with MASLD, MASH and ALD, you may not know you have it. It’s usually detected during a routine blood test, where abnormal liver function may cause your doctor to order further testing.

To diagnose the disease, your doctor will ask about your family history and perform a physical exam. They’ll then ask about your medical history, including your alcohol use and what medications you take, as certain medications can cause MASLD.

Your doctor will likely order an ultrasound first to look at your liver. They may also order more blood tests, like a liver function test, and imaging tests like magnetic resonance imaging (MRI) or computed tomography (CT) scan to determine the level of fat in your liver. Depending on the results of those tests, they may refer you to a liver specialist known as a hepatologist.

If you have excess fat present in your liver, but no inflammation, you’ll be diagnosed with MASLD. If you have fat and inflammation, your diagnosis will be MASH.

Recommended treatments for MASLD, MASH and ALD (fatty liver disease)

There isn’t a specific cure for steatotic liver disease. It’s best treated with simple lifestyle changes such as weight loss and other things that can help to improve the health of your liver.

Self-care and diet can help treat and prevent MASLD, MASH and ALD

Changes you can make to help treat symptoms don’t have to be drastic. Steps you can take include:

• Losing weight – While losing any percentage of your body weight is helpful, doctors frequently recommend losing around 10% to reduce fat in the liver, as well as liver inflammation and fibrosis.
• Improving your sleep – Poor quality sleep has been linked to a small risk of developing MASLD and MASH, so it’s important to have good sleep hygiene. In addition to managing any sleep disorders you may have, making small adjustments to your routine and environment can help to ensure that you get enough good, quality sleep.
• Eating a healthy diet – Eating healthy foods is easier said than done, but to treat MASLD and MASH, it can be helpful to adopt a Mediterranean diet that’s heart-healthy, and consists of fruits and veggies, whole grains, nuts, beans, fish and other seafood. It also incorporates poultry and dairy in moderation and saves red meat and sweets for special occasions.
• Cutting back or avoiding certain beverages – A diet includes what you drink, too. Beverages that have high fructose corn syrup and other added sugars can be converted into fat that’s stored in the liver cells, so it’s important to cut back or eliminate them completely to lower your risk.
• Lowering your blood pressure, triglycerides and cholesterol – Fat in the liver can raise your blood pressure, and a diet high in triglycerides and cholesterol can increase the risk of developing MASLD and MASH. While these levels can be controlled with medications, you can also lower your levels naturally by losing weight, improving your diet and more.
• Cutting back or avoiding alcohol – Consuming large quantities of alcohol, even for a short period of time, can increase the risks of developing ALD. The most effective way to reduce your risk is to stop drinking alcohol completely. This should be done safely – if you feel you need support to help you stop drinking, reach out to your doctor.
• Properly controlling diabetes – Type 2 diabetes and steatotic liver diseases are often linked. When blood sugar isn’t controlled in the body, it can cause damage to internal organs, including the liver. And increased fat in the liver can raise blood sugar levels in the body, making it tough to manage diabetes. Managing diabetes properly not only helps with your diabetes symptoms but it can also help reduce your risk of developing MASLD and MASH.
• Easing stress on your liver – Some over-the-counter and prescription medications and supplements can cause liver damage, especially if there’s existing liver disease, they’re used more than prescribed or they’re used in combination with alcohol. Cutting back or eliminating the use of these medications can help treat your symptoms, but make sure you work with your doctor to determine what’s best for you.

Medications and supplements that can help MASLD and MASH

Based on your unique situation, your doctor may talk to you about medications available to help MASLD and MASH. Recently, the FDA approved a drug (resmetirom) that was initially approved to help lower levels of unhealthy fats in the body, like cholesterol, but it was discovered that it can help treat MASLD and MASH as well.

Medications, alongside diet and lifestyle changes, can lower the risk of liver scarring and slow the progression of disease. In addition, based on your situation, your doctor may also recommend the following:

• Taking metabolic medications as prescribed – If you’re taking prescribed metabolic medications, like diabetes medication and anti-obesity medications, or medications that help reduce blood pressure, cholesterol and triglycerides, it’s important to take them exactly as prescribed. While they’re not approved to cure or treat steatotic liver disease, they can help control some of the factors that cause it if they’re taken correctly.
• Staying current on your hepatitis A and B vaccines – Hepatitis is a disease that affects the liver. There are several different kinds, but two of them – hepatitis A and B – have vaccines. By staying up to date on your hepatitis vaccines, you can lower your risks of developing preventable liver disease and help reduce complications if you develop or already have a liver disease.

It’s important to treat MASLD and MASH (fatty liver disease)

Depending on the type, steatotic liver disease isn’t usually dangerous, especially if it’s diagnosed and treated early. Your best option to treat it is to make simple changes to your diet and lifestyle, but if you feel like the changes you’re making don’t seem to be working, or you need extra support, reach out to your doctor. They can help you with a treatment plan that can help protect your liver, improve your health, and slow or stop the progression of MASLD, MASH and ALD, no matter the cause.