PPIG and Hepatic fibrosis: On the contrary, in the absence of NAFLD, the levels of oxidative stress, inflammatory cytokines, and free radicals are all lower, and there is also less activity of CYP isoenzymes, resulting in a less favorable environment for the toxic effects of safrole and arecoline, which might provide some explanations for the insignificant relationship between betel nut chewing and liver fibrosis among the subjects without NAFLD.