What Causes Fatty Liver?

Most people with fatty liver do not have symptoms even as the disease progresses. This silent disease may lead to cirrhosis or liver cancer if left untreated.

What Is Fatty Liver?

The liver is the largest organ inside the body and is responsible for various essential functions that help enable metabolism, immunity, digestion, detoxification and vitamin storage. It is the only organ in the body capable of regenerating after damage, but many diseases can harm it beyond the point of repair. It is normal for the liver to contain some fat. However, fatty liver or steatosis occurs when 5-10% of the liver's weight is fat.

What Is the Main Cause of a Fatty Liver?

The two main types of fatty liver disease are nonalcoholic and alcoholic fatty liver disease. 

  • Nonalcoholic fatty liver disease (NAFLD)

    About 100 million people in the United States are estimated to have nonalcoholic fatty liver disease. It occurs when excess fat builds up in the liver cells unrelated to heavy alcohol use. NAFLD usually affects people who are overweight and obese. Having diabetes, high cholesterol or high triglycerides can also increase your risk of developing NAFLD. Rapid weight loss and poor eating habits may also lead to this condition. The two types of NAFLD are simple fatty liver and nonalcoholic steatohepatitis (NASH).

  • Alcoholic fatty liver disease (alcoholic steatohepatitis)
    Each time you drink alcohol, some of your liver cells die. Prolonged alcohol misuse over time can result in severe and permanent liver damage. Alcoholic fatty liver disease is the earliest stage of alcohol-related liver disease which may lead to alcoholic hepatitis and cirrhosis.

What Are the Symptoms of Fatty Liver?

Both types of fatty liver disease are silent diseases with few or no symptoms. When symptoms occur, a person may experience abdominal pain in the upper right side of the abdomen and sometimes fatigue. Doctors may use blood tests, imaging tests and sometimes, a biopsy to diagnose fatty liver disease.

How to Reverse Fatty Liver?

You may be able to prevent or treat some types of fatty liver disease through healthy lifestyle changes. Your doctor may recommend gradually losing weight if you are overweight or obese. Other recommendations may include:

  • Limit your intake of fats and replace saturated fats and trans-fat in your diet with unsaturated fats found in omega-3 fatty acids, which may help reduce your risk of heart disease if you have NAFLD.
  • Consume more low-glycemic index foods, such as most fruits and vegetables and whole grains.
  • Avoid sugary foods and drinks, especially those containing large amounts of fructose, such as soft drinks, sports drinks, sweetened tea and juices.
  • Limit or avoid alcohol intake.


Taking steps against this silent disease can help reverse or slow its progression. It can be challenging to treat fatty liver disease once it has progressed. If you think you have fatty liver disease, visit a gastroenterologist as your first step. Please don't delay care. We're here for you always.


American Liver Foundation
National Center for Biotechnology Information
NHS Inform
National Institute of Diabetes and Digestive and Kidney Diseases
National Institutes of Health

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