Metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are liver diseases that are becoming more common, especially in people with obesity, diabetes, high blood pressure, and high cholesterol. These diseases were previously called nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), but experts updated the names to better reflect their connection to metabolic health.

MASLD means your liver has too much fat. This can happen even if you don’t drink alcohol. MASLD is often found in people who are overweight or have diabetes. More than a third of the world’s population has MASLD.

MASH is a more serious form of liver disease. This means that your liver is not only fatty, but also inflamed and damaged.

Which of these liver diseases you have, along with several other factors, is key to understanding your outlook, also called prognosis.

Understanding MASLD and MASH results

Many people with MASLD do not have liver-related complications, especially if they lower their metabolic rate risk factors. Research shows that people with MASLD live an average of about three years less than those without the condition. MASLD can increase the risk of heart disease and certain types of cancer. And up to 20% to 30% of people with MASLD may develop MASH.

With MASH, inflammation and damage can lead to scarring, also called fibrosis; cirrhosis, which is severe scarring; and liver cancer over time. These conditions have a major impact on survival rates.

Factors affecting results

Healthcare professionals use a system called staging of fibrosisfrom F0 to F4, to measure how much damage there is in the liver.

People with F3 or F4 fibrosis are at greater risk of liver failure and cancer. The average 10-year survival rates reflect this.

• F0 to F2: About 89% to 93%.
• F3: About 81%.
• F4, also called cirrhosis: About 51%, depending on complications.

Worsening of scarring to cirrhosis is typically slow and takes years to decades. On average, people with MASH move to the next stage of fibrosis approximately every seven years, compared to every 14 years in those with MASLD.

People who have scarring of the liver without major complications, called compensated cirrhosis, have higher survival rates than those with scarring with major complications, known as decompensated cirrhosis. Complications include abdominal fluid buildup, called ascites; gastrointestinal bleeding, also called variceal bleeding; and confusion, known as hepatic encephalopathy. For people with decompensated cirrhosis, the average survival time is 2 to 3 years without receiving a liver transplant.

Other factors that affect the prognosis include:

Heart health. Heart disease is the No. 1 cause of death in people with MASLD or MASH. That’s because these liver diseases often come with high blood pressure, high cholesterol and diabetes – all of which hurt the heart.

Diabetes and obesity. Having diabetes or being overweight worsens liver health. It also increases the risk of kidney problems and other health problems.

Age and gender assigned at birth. Older people tend to have more liver damage. Men may be more likely to develop severe scarring, while women may have more fat in the liver but slower progression until they reach menopause.

Lifestyle. Drinking alcohol, eating less healthy food and not exercising can make liver disease worse. But healthy habits can slow or even reverse damage.

Genes. Some people have genetic traits that make them more prone to liver damage. Scientists are still learning how to use this information to help people with liver disease.

The good news is that MASLD and MASH can often be managed — and sometimes improved — with lifestyle changes. For example, losing just 7% to 10% of your body weight can reduce liver fat and inflammation. To eat one Mediterranean-style diet that includes plenty of fruits, vegetables, whole grains and healthy fats can also improve liver health.