Fatty liver disease means that you have extra fat inside your liver. This extra fat keeps your liver from doing a good job of removing toxins from your blood. People who drink too much alcohol may have fat in their liver. When the fatty liver does not come from drinking too much alcohol, it is called nonalcoholic fatty liver disease.
There are 2 types:
Nonalcoholic fatty liver disease (NAFLD). This type is when you have fat in your liver. But your liver is not damaged. It is also called metabolic dysfunction-associated fatty liver disease (MAFLD)
Nonalcoholic steatohepatitis (NASH). This type is when you have fat in your liver. You also have signs of inflammation and liver cell damage.
Healthcare providers don’t know the exact cause of nonalcoholic fatty liver disease. Certain health conditions are closely linked to NAFLD. These include obesity, insulin resistance, metabolic syndrome, type 2 diabetes, high cholesterol, and high triglycerides. These conditions may lead to extra fat in the liver or fatty liver disease.
Children and young adults can get this disease. But it is most common in middle age. Risk factors include:
Being overweight or obese, especially having too much belly fat (central obesity)
Having high blood fat levels (either triglycerides or LDL cholesterol)
Having type 2 diabetes or prediabetes
Having high blood pressure
When these risk factors happen together, they cause a health problem called metabolic syndrome. People with metabolic syndrome often have fatty liver. They also are more likely to have heart disease. Other conditions that may raise your risk include polycystic ovary syndrome, sleep apnea, and hypothyroidism.
Nonalcoholic fatty liver disease is sometimes called a silent liver disease. This is because it can happen without causing any symptoms. Most people with NAFLD live with fat in their liver without getting liver damage. A few people who have fat in their liver develop nonalcoholic steatohepatitis (NASH).
If you have NASH, you may have symptoms. But it could take years for them to show up. Sometimes liver damage from NASH causes long-term scarring and hardening of your liver. This is called cirrhosis. It also increases risk for liver cancer. Symptoms from NASH may include:
Severe tiredness (fatigue)
Pain in the right upper belly (abdomen)
Yellowing of the skin or eyes (jaundice)
Spiderlike blood vessels on the skin
NASH that turns into cirrhosis could cause these symptoms:
Extra fluid buildup (fluid retention)
These symptoms may look like other health problems. Always see your healthcare provider for a diagnosis.
Nonalcoholic fatty liver disease can happen without causing any symptoms. It’s often diagnosed when you have routine blood tests to check your liver. Your healthcare provider may think you have it if your test results are abnormal. This is especially true if you are obese or have diabetes.
Your healthcare provider may use these tests to help make a diagnosis:
Imaging tests. Ultrasound, CT scan, or MRI may show fat deposits in your liver.
Blood test. A special blood test can check how diseased your liver is.
Liver biopsy. The provider puts a long needle through your skin into your liver. The needle removes a small piece of liver tissue. The tissue can be looked at under a microscope.
Based on the test results, your healthcare provider will make the following diagnosis:
You have NAFLD if you have fat but no inflammation or tissue damage.
You have NASH if you have fat, inflammation, and liver damage.
You may be developing cirrhosis if you have a type of scar tissue in your liver called fibrosis.
If you have NAFLD without any other health problems, you don’t need any special treatment. But making some lifestyle changes can control or reverse the fat buildup in your liver. These may include:
Lowering your cholesterol and triglycerides
Controlling your diabetes, if needed
Not drinking alcohol
If you have NASH, no medicine can fully reverse the fat buildup in your liver. Sometimes the liver damage stops or even reverses itself. But for other people, the disease keeps getting worse. If you have NASH, it’s important to control any conditions that may help cause the disease. Treatments and lifestyle changes may include:
Taking medicine to lower cholesterol or triglycerides
Taking medicine to lower blood pressure
Taking medicine to control diabetes
Limiting over-the-counter medicines
Not drinking alcohol. No amount of alcohol is known to be fully safe once you have NASH.
Eating a diet low in fat and simple carbohydrates
Seeing a liver specialist
Your provider may advise certain medicines if you have NASH. These include vitamin E in people without diabetes or heart disease. And they include pioglitazone, a diabetes medicine for people with or without diabetes. But these have side effects, so talk about them with your healthcare provider. Other medicines, including certain herbal supplements, are being looked into. Treating the underlying conditions is the absolute most important thing, and is more effective than any medicine.
The main complication is that NASH can become cirrhosis. Cirrhosis means lasting (permanent) scarring and hardening of the liver. People with cirrhosis may develop liver failure and need a liver transplant. NASH may also progress to liver cancer. Talk with your healthcare provider about any concerns you may have.
If you have nonalcoholic fatty liver disease, learn as much as you can about your condition. Work closely with your healthcare team. Many medicines can harm your liver. So always tell all your healthcare providers about any medicines you are taking. These include over-the-counter medicines, dietary supplements, herbs, and vitamins.
Other ways to manage the disease include:
Staying at a healthy weight
Eating a balanced diet
Getting regular exercise
Be sure to ask your healthcare provider about recommended vaccines. These include vaccines for viruses that can cause liver disease.
Call your healthcare provider if you have any symptoms that mean nonalcoholic fatty liver disease is getting worse. These are:
Loss of appetite
Fatty liver disease means that you have extra fat inside your liver. When this is not caused by drinking too much alcohol, it is called nonalcoholic fatty liver disease or metabolic dysfunction-associated liver disease.
Obesity may be the most common cause of this disease.
Nonalcoholic fatty liver disease can happen without causing any symptoms.
Blood tests and imaging tests, such as a CT scan and ultrasound, can help diagnose it.
Losing weight and making other lifestyle changes can help control and even reverse this disease.
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.