Nonalcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease in North America.

Some people with excess fat in the liver simply have what's called a fatty liver. Although this is not normal, it's not serious if it doesn't lead to inflammation or damage. However, once there's a buildup of simple fat, the liver becomes vulnerable to injury which may result in inflammation and scarring of the liver. Others have what's called Nonalcoholic Steatohepatisis (NASH). Although it is similar to alcoholic liver disease, people with this type of...