From Medscape:

Nonalcoholic fatty liver disease (NAFLD) … similar to alcoholic hepatitis but developing in the absence of alcoholism. Most of their patients were modestly obese and some had diabetes mellitus. NAFLD is the most frequent cause of abnormal liver tests in both adults and children.^[3]

NAFLD is common.^[4] The National Health and Nutrition Examination Survey (NHANES) III of American adults indicates that up to 23% may be affected.^[5,6] …  NAFLD also affects all ages: An autopsy study found fatty liver in nearly 10% of adolescents,^[9]