Nonalcoholic steatohepatitis or NASH is a common, often “silent” liver disease. It resembles alcoholic liver disease, but occurs in people who drink little or no alcohol. The major feature in NASH is fat in the liver, along with inflammation and damage. Most people with NASH feel well and are not aware that they have a liver problem. Nevertheless, NASH can be severe and can lead to cirrhosis, in which the liver is permanently damaged and scarred and no longer able to work properly. NASH affects 2 to 5 percent of Americans. An additional 10 to 20 percent of Americans have fat in their liver, but no inflammation or liver damage, a condition called “fatty liver.” Although having fat in the liver is not normal, by itself it probably causes little harm or permanent damage.

If fat is suspected based on blood test results or scans of the liver, this problem is called nonalcoholic fatty liver disease (NAFLD). If a liver biopsy is performed in this case, it will show that some people have NASH while others have simple fatty liver. Both NASH and NAFLD are becoming more common, possibly because of the greater number of Americans with obesity. In the past 10 years, the rate of obesity has doubled in adults and tripled in children. Obesity also contributes to diabetes and high blood cholesterol, which can further complicate the health of someone with NASH. Diabetes and high blood cholesterol are also becoming more common among Americans.

Points to Remember
*Nonalcoholic steatohepatitis (NASH) is fat in the liver, with inflammation and damage.
*NASH occurs in people who drink little or no alcohol and affects 2 to 5 percent of Americans, especially people who are middle-aged and overweight or obese.
*NASH can occur in children.
*People who have NASH may feel well and may not know that they have a liver disease.
*NASH can lead to cirrhosis, a condition in which the liver is permanently damaged and cannot work properly.
*Fatigue can occur at any stage of NASH.
*Weight loss and weakness may begin once the disease is advanced or cirrhosis is present.