Non-Alcoholic Fatty Liver Disease: A Practical Guide - Hardcoverby Heidi Hamlin (Editor) Non alcoholic fatty liver disease (NAFLD) refers to the building up of extreme fat in the liver without any clear cause like alcohol use. NAFLD is categorized into two types that include non alcoholic steatohepatitis (NASH), which also involves liver inflammation, and non alcoholic fatty liver (NAFL). Non alcoholic fatty liver is less risky when compared to NASH. Typically, it does not develop to the stage of liver cirrhosis