Steatotic Liver Disease (Fatty Liver): Types, Risks and Treatment

Your liver is the largest organ inside your body. It helps you digest food, store energy and remove toxins. Steatotic liver disease — formerly called fatty liver disease — is when too much fat builds up in it. Some fat in liver cells is normal; too much can cause trouble.

The two main types

MASLD's two forms

• Simple fatty liver: fat in the liver with little or no inflammation or damage. It usually doesn't progress far enough to cause damage or complications.
• MASH (metabolic dysfunction-associated steatohepatitis, formerly NASH): a worse form, with inflammation and liver damage on top of the fat. It can cause fibrosis (scarring), which sometimes leads to cirrhosis or liver cancer.

How alcohol harms the liver

The liver breaks down most of the alcohol you drink so your body can get rid of it — but that process produces harmful substances that can damage liver cells, cause inflammation and weaken your body's natural defenses. The more you drink, the more damage. ALD is the earliest stage of alcohol-related liver disease; the next stages are alcoholic hepatitis and cirrhosis.

Who's at risk

MASLD is the most common chronic liver disease, driven by rising rates of obesity, type 2 diabetes and high cholesterol. It's more common in people who:

• have type 2 diabetes or prediabetes;
• have obesity;
• are middle-aged or older (though children can get it too);
• have high cholesterol or triglycerides, or high blood pressure;
• take certain medicines, such as corticosteroids and some cancer drugs;
• have certain metabolic disorders, including metabolic syndrome;
• have lost weight rapidly;
• have certain infections, such as hepatitis C;
• have been exposed to certain harmful substances.

ALD happens only in heavy drinkers, especially those who've drunk heavily for a long time. Among heavy drinkers, risk is higher for women, people with obesity and people with certain gene variants.

Symptoms

Both types usually cause few or no symptoms. When they do, you may feel tired or have discomfort in the upper right side of your belly.

Diagnosis

With so few symptoms, it's hard to catch. A provider may suspect it after abnormal liver test results, then use:

• your medical history, including alcohol use and medicines;
• a physical exam — height and weight, and signs of liver disease such as an enlarged liver or jaundice (yellowing of the skin and whites of the eyes);
• blood tests, such as liver function tests and blood counts;
• imaging to check for fat and fibrosis in the liver;
• sometimes a biopsy to confirm the diagnosis and check for damage.

Treatment

MASLD

• The first step is usually weight loss, which can reduce liver fat, inflammation and fibrosis.
• If a medicine may be the cause, your provider may have you stop or switch it — but don't stop any medicine on your own.
• No medicines are currently approved to treat MASLD; more research is needed.

ALD

• The most important step is to stop drinking. Counseling, a recovery program, or medicines that reduce cravings or make you feel sick if you drink can help.

Cirrhosis. ALD and one type of MASLD can lead to cirrhosis. Its complications can be treated with medicines, surgery and other procedures; if it causes liver failure, a liver transplant may be needed.

Lifestyle changes that help

For any type of steatotic liver disease:

• Eat well: limit salt and sugar, and eat plenty of fruits, vegetables and whole grains.
• Exercise regularly — it helps you lose weight and reduces liver fat.
• Ask about vaccines. Chronic liver disease raises your risk of infection; your provider may recommend vaccines for hepatitis A and B, flu and pneumococcal disease.
• Check before taking supplements, vitamins or complementary and alternative medicines — some supplements and herbal remedies can damage the liver.

Sources

Based on "Steatotic Liver Disease," MedlinePlus, U.S. National Library of Medicine; a work of the United States government in the public domain.