Nonalcoholic steatohepatitis (NASH) is liver inflammation caused by a buildup of fat in the liver. Many people have a buildup of fat in the liver, and for most people it causes no symptoms and no problems. But in some people, the fat causes inflammation of the liver. Because of the inflammation, the liver doesn’t work as well as it should.
NASH can get worse and cause scarring of the liver, which leads to cirrhosis. But the disease doesn’t always get worse.
NASH is similar to the kind of liver disease that is caused by long-term, heavy drinking. But NASH occurs in people who don’t abuse alcohol.
What causes NASH?
Experts don’t know why some people with a buildup of fat in the liver get NASH and some don’t. It could be that something in the environment triggers the inflammation in those people. Or maybe it runs in their families.
Things that put people at risk for NASH and for liver damage include:
- Type 2 diabetes.
- High cholesterol and high triglycerides.
- Metabolic syndrome.
Most people who have NASH are 40 to 50 years old and have one or more of the problems listed above. But NASH can happen in people who have none of these risk factors.
What are the symptoms?
You may have no symptoms in the early stages of NASH. Most people who have NASH feel fine and don’t know that they have it.
As NASH progresses and liver damage gets worse, you may start to have symptoms such as:
- Fatigue (feeling tired all the time).
- Weight loss for no clear reason.
- General weakness.
- An ache in the upper right part of your belly.
It may take many years for NASH to become severe enough to cause symptoms.
How is NASH diagnosed?
No single test can diagnose NASH. Your doctor will ask you about other health problems you’ve had.
To see if fat is building up in your liver and to rule out other diseases, your doctor may do tests such as:
- An abdominal ultrasound.
- A CT scan.
- An MRI scan.
Your doctor may do a liver biopsy to be sure that you have NASH. In a liver biopsy, your doctor takes a sample of tissue from your liver and checks it for signs of NASH.
How is it treated?
There is no treatment for NASH. But you may be able to limit damage to your liver by managing conditions that increase your risk for NASH or make it worse. You can:
- Reduce your total cholesterol level.
- Reach a healthy weight. If you need to lose weight, be sure to do so slowly (no more than 1 to 2 pounds a week).
- Control diabetes.
- Stop or cut back on drinking alcohol.
- Exercise regularly.
Also, ask your doctor or pharmacist about all the medicines you are taking. Some may harm your liver.