Causes

Experts don't know exactly why some people accumulate fat in the liver while others do not. Similarly, there is limited understanding of why some fatty livers develop inflammation that progresses to cirrhosis.

NAFLD and NASH are both linked to the following:

• Overweight or obesity
• Insulin resistance, in which your cells don't take up sugar in response to the hormone insulin
• High blood sugar (hyperglycemia), indicating prediabetes or type 2 diabetes
• High levels of fats, particularly triglycerides, in the blood

These combined health problems appear to promote the deposit of fat in the liver. For some people, this excess fat acts as a toxin to liver cells, causing liver inflammation and NASH, which may lead to a buildup of scar tissue in the liver.