- Diagnosis of nonalcoholic steatohepatitis (NASH) and a NAFLD (nonalcoholic fatty liver disease) activity score (NAS) >= 5; NOTES and EXCEPTIONS: NAS is based on findings from a liver biopsy; participants with NAS of =< 2 are eligible for enrollment; participants with NAS of 3-4 must be discussed with the principal investigator and Division of Cancer Prevention (DCP) before enrollment to consider other risk factors (i.e., obesity, alcohol intake); participants with a prior diagnosis of NASH and no available NAS must be discussed with the principal investigator and DCP before enrollment to considered risk factors (i.e., obesity, alcohol intake)