Understanding Fatty Liver Disease

There are two main categories of fatty liver disease, based on the underlying cause:

• Alcohol-associated liver disease (ALD):
  Fatty liver disease caused by regular or excessive alcohol consumption. Alcohol can lead to fat accumulation in the liver and, over time, inflammation, fibrosis, cirrhosis, or liver failure.

• Metabolic dysfunction–associated steatotic liver disease (MASLD):
  Formerly known as nonalcoholic fatty liver disease (NAFLD), MASLD is not caused by alcohol use. Instead, it is associated with metabolic conditions such as obesity, insulin resistance, type 2 diabetes, high blood pressure, and abnormal cholesterol levels. MASLD affects approximately one in three adults and an increasing number of children in the United States.

  When MASLD progresses to liver inflammation and injury, it is referred to as metabolic dysfunction–associated steatohepatitis (MASH) (formerly NASH), which carries a higher risk of fibrosis, cirrhosis, and liver-related complications.

Not everyone with fatty liver disease will progress to advanced stages.  Early identification and lifestyle changes can alter the course of the disease.

Fatty liver disease often has no signs or symptoms, especially in the early stages. When symptoms do occur, they may include:

• Generalized malaise or feeling unwell

• Fatigue

• Intermittent discomfort or pain in the upper right abdomen

As fatty liver disease progresses to advanced fibrosis or cirrhosis, additional signs and symptoms may develop, including:

• Itchy skin

• Abdominal swelling due to fluid buildup (ascites)

• Mental confusion (hepatic encephalopathy) or extreme fatigue

• Shortness of breath

• Yellowing of the skin and eyes (jaundice)

• Enlarged spleen

• Swelling of the legs and/or genital area

• Spider-like blood vessels on the skin (spider angiomas)

• Nausea and loss of appetite

• Unintentional weight loss

Imaging studies are commonly used to detect fatty liver disease and assess the degree of liver damage.

• Abdominal Ultrasound – A noninvasive test used to evaluate the organs and structures within the abdomen. It is often the first imaging study used to detect fatty changes in the liver.

• Computed Tomography (CT Scan) – Uses a combination of X-rays and computer technology to create detailed cross-sectional images of the liver and surrounding structures. CT scans can identify fatty infiltration and evaluate for other liver abnormalities. Contrast is sometimes used to enhance image detail.

• Magnetic Resonance Imaging (MRI) – Produces highly detailed images of the liver using a powerful magnet and radio waves. MRI is more sensitive than ultrasound or CT for detecting liver fat.

• Magnetic Resonance Elastography (MRE) – An advanced MRI-based technique that combines imaging with low-frequency vibrations to create a visual map (elastogram) of liver stiffness. MRE is one of the most accurate noninvasive tools for assessing liver fibrosis and inflammation.

• FibroScan® (Transient Elastography) – A specialized ultrasound-based test that measures liver stiffness and fat content. It is commonly used to stage fibrosis and monitor disease progression or improvement over time.

Blood tests help evaluate liver function, metabolic health, and possible causes of liver injury. No single blood test can diagnose MASLD or MASH on its own, but together they provide important clues.

Common Blood Tests

• Complete Blood Count (CBC)
  Looks at red blood cells, white blood cells, and platelets. Low platelets can be a sign of advanced liver disease.

• Hemoglobin A1c (A1c)
  Measures average blood sugar over 3 months. Higher levels are commonly associated with MASLD and MASH.

• Lipid Panel
  Measures cholesterol and triglycerides, which are often elevated in metabolic liver disease.

• Comprehensive Metabolic Panel (CMP)
  Includes electrolytes, kidney function, and liver-related values such as bilirubin and albumin.

• Prothrombin Time / INR (PT/INR)
  Assesses blood clotting, which can be affected when liver function declines.

Liver Enzymes

Liver enzymes are released into the blood when liver cells are stressed or injured.

• ALT (Alanine Aminotransferase)
  Most specific to the liver and often elevated early in liver disease.

• AST (Aspartate Aminotransferase)
  Found in the liver and other tissues; elevations may indicate liver injury.

• Alkaline Phosphatase (ALP)
  Can rise with bile duct problems or certain liver conditions.

• GGT (Gamma-Glutamyl Transferase)
  Often elevated with liver disease and alcohol exposure; helps clarify the source of abnormal ALP.

• Bilirubin
  A yellow pigment processed by the liver. Elevated levels can cause jaundice and signal impaired liver function.

Additional Testing (When Needed)

If liver enzymes are persistently elevated, additional blood tests may be ordered to rule out other treatable liver conditions, such as:

• Viral hepatitis (A, B, C)

• Autoimmune liver disease

• Alpha-1 antitrypsin deficiency

• Wilson’s disease

• Hemochromatosis (iron overload)

Calculated Liver Scores

Some blood tests are combined into scores that help estimate liver severity:

• FIB-4 Score
  A noninvasive estimate of liver fibrosis based on age, AST, ALT, and platelet count.

  • Low score → minimal fibrosis

  • Higher score → increased risk of advanced fibrosis

• MELD 3.0 Score
  Used only in advanced liver disease to assess severity and transplant priority.

A liver biopsy is a procedure in which a small sample of liver tissue is removed and examined under a microscope. This allows for detailed evaluation of inflammation, scarring (fibrosis), and other underlying liver conditions.

While a liver biopsy is considered the gold standard for diagnosing and staging liver disease, it is not routinely required for most people with MASLD or MASH. It is typically reserved for select cases when the diagnosis is unclear or when results will significantly impact treatment decisions.

Sedation is usually provided to improve comfort during the procedure.

Common Types of Liver Biopsy

• Percutaneous (most common)
  A thin needle is inserted through the abdominal wall to obtain a small sample of liver tissue.

• Transjugular
  A vein in the neck is used to access the liver and obtain a tissue sample. This method is often chosen for people with ascites, bleeding or clotting disorders, or advanced liver disease.

• Laparoscopic
  Performed during abdominal surgery (such as gallbladder removal), allowing a liver biopsy to be completed at the same time.

The Standard American Diet is a major contributor to the development and progression of fatty liver disease. Diets high in ultra-processed foods, added sugars, and refined carbohydrates promote insulin resistance, inflammation, and fat accumulation in the liver—contributing not only to the development of fatty liver disease, but also to progression to more advanced stages. (And yes, the irony of the acronym “SAD” is not lost on me.)

The Mediterranean diet has long been recommended as an effective dietary approach for slowing progression and, in some cases, improving fatty liver disease. This eating pattern emphasizes whole, nutrient-dense foods such as vegetables, fruits, legumes, nuts, olive oil, fatty fish, white meat, and minimally processed whole grains, while limiting ultra-processed foods, sweets, processed meats, and red meat.

The Mediterranean diet is rich in antioxidants and anti-inflammatory compounds, which support liver health and improve insulin sensitivity. Beyond liver benefits, this dietary pattern has been associated with reduced risk of cardiovascular disease, type 2 diabetes, cognitive decline, and chronic inflammation, while supporting better sleep, cognition, and overall longevity.

Importantly, the Mediterranean diet is not overly restrictive and allows for cultural and regional variation, making it a sustainable long-term lifestyle rather than a short-term diet.

Coffee is one of the most widely consumed beverages in the world, and fortunately, there is strong evidence that it is beneficial for liver health. Research shows that people who drink coffee have a lower risk of developing fatty liver disease in the first place. Among those who already have fatty liver disease, coffee appears to have a protective effect by reducing liver inflammation and slowing the progression of fibrosis—the scarring process that can ultimately lead to cirrhosis.

Even among individuals with established cirrhosis, coffee consumption has been associated with lower liver-related mortality. In short, when it comes to liver health, coffee keeps getting better.

Is decaf good for your liver?
Unfortunately, most of the liver-protective benefits appear to be linked to caffeine. During caffeine metabolism, the body produces a compound called paraxanthine, which has been shown to slow the development of liver fibrosis. In addition to caffeine, coffee contains more than 1,000 biologically active compounds, and research is ongoing to determine which of these contribute to its liver benefits.

How much coffee is recommended?
Most studies suggest that at least 2 cups per day are needed to see liver-protective effects. In one study, consuming 2 cups daily was associated with a 44% reduction in the risk of cirrhosis, while 4 cups daily reduced the risk by up to 65%.

That said, not everyone tolerates this amount of coffee. Individuals with heart rhythm issues, significant anxiety, insomnia, or other caffeine sensitivity should avoid forcing higher intake and should discuss coffee consumption with their healthcare provider.

To maximize benefit, skip the creamers, sugar, and artificial sweeteners. Stick with black coffee when possible—organic if available.

Time-restricted eating (TRE) and intermittent fasting (IF) are increasingly recognized as effective tools for improving metabolic health and reducing liver fat in people with fatty liver disease. These approaches focus on when food is consumed rather than strictly what is eaten, and have been shown to improve insulin sensitivity, promote weight loss, and reduce liver inflammation—key drivers of MASLD and MASH.

Intermittent fasting involves alternating periods of eating with planned periods of fasting, most commonly through a daily eating window (for example, eating within an 8–10 hour window and fasting the remaining hours). This structured reduction in eating time allows the liver to shift away from constant glucose and insulin exposure, supporting metabolic repair and fat mobilization.

Fasting has been practiced for centuries for cultural and religious reasons, but modern research now supports its role in metabolic disease management. Emerging evidence suggests that when you eat can be just as important as what you eat, particularly for liver health.

Important safety note:
Intermittent fasting may be beneficial for individuals with fatty liver disease without advanced liver disease, but it is not recommended for patients with cirrhosis, who require more consistent caloric and protein intake to prevent muscle loss and complications. As with any dietary strategy, fasting should be individualized and discussed with a healthcare provider.

Exercise provides meaningful benefits for liver health independent of weight loss. Research shows that physical activity can reduce liver fat, improve insulin sensitivity, and lower inflammation—even when the number on the scale doesn’t change.

While studies vary on the optimal type and intensity of exercise, consistent moderate-intensity activity totaling at least 150 minutes per week, ideally spread over 4–5 sessions, has been shown to improve or prevent fatty liver disease. Examples include walking, hiking, swimming, cycling, mowing the lawn, or gardening.

Some evidence suggests that higher-intensity exercise may offer additional benefit, particularly for reducing liver fibrosis. Activities such as running, brisk walking, HIIT (high-intensity interval training), stair climbing, resistance training, burpees, or cross-country skiing fall into this category. That said, intensity should always be tailored to an individual’s fitness level and medical conditions.

The greatest and most sustainable improvements in liver health occur when exercise is combined with dietary and lifestyle changes.

And remember—you can’t outrun a bad diet.

Weight Loss Surgery:  Benefits and Limitations

Bariatric surgery includes invasive procedures used to treat obesity and obesity-related conditions. Fatty liver disease is increasingly recognized as an obesity-related condition that may benefit from surgical weight loss.

Accepted criteria for bariatric surgery include a BMI ≥ 40 kg/m² without additional medical conditions, or a BMI ≥ 35 kg/m² in the presence of comorbidities such as type 2 diabetes, uncontrolled hypertension, osteoarthritis, or urinary incontinence. Growing evidence suggests that bariatric surgery can significantly improve hepatic steatosis and may improve liver inflammation and fibrosis in appropriately selected patients.

The most common bariatric procedures include sleeve gastrectomy and Roux-en-Y gastric bypass. Less invasive, endoscopic bariatric therapies are an emerging area of interest and may expand treatment options in the future. Individuals with cirrhosis are at increased risk for postoperative complications and mortality, and careful preoperative evaluation is essential.

Bariatric surgery is a tool, not a cure. While many individuals experience durable weight loss and metabolic improvement, long-term success depends heavily on sustained lifestyle changes. Habits are difficult to break — and unfortunately, behavior modification isn’t included in the surgical package 😉.

In March 2024, the FDA granted accelerated approval to resmetirom (Rezdiffra) as the first treatment for adults with MASH and moderate-to-advanced liver fibrosis (F2-F3), to be used in combination with diet and lifestyle modification.  In August 2025, semaglutide (Wegovy) received FDA approval for the treatment of adults with MASH and F2-F3 fibrosis without cirrhosis, becoming the first GLP-1 receptor agonist approved for this indication. 

These medications work through different mechanisms and may be appropriate for different patients depending on fibrosis stage, metabolic profile, and comorbid conditions. 

The chart below includes medications approved for treatment of other medical conditions that have shown some benefits for treatment of fatty liver disease.

FDA-approved treatments for MASH

Medications approved for other conditions with potential liver benefit

The medications listed above are approved for the treatment of metabolic conditions that commonly coexist with fatty liver disease. Several have demonstrated improvements in liver fat, inflammation, and metabolic risk factors, but are not currently FDA-approved specifically for MASH unless otherwise noted.

There are multiple medications currently in various stages of clinical trials targeting inflammation, fibrosis, and metabolic dysfunction in MASH. This remains a rapidly evolving area of research, and additional treatment options are expected in the coming years.