The assessment of liver fibrosis has gained importance since the progression of non-alcoholic fatty liver disease (NAFLD). Indeed, the description of the association between undetected liver fibrosis and lifestyle in terms of antioxidant habits, comorbidity and quality of life (QoL) domains may help in the characterization of subjects with NAFLD. A cross-sectional evaluation of (n = 116) consecutive patients from an Internal Medicine ambulatory evaluation was performed. Demographic data, lifestyle, co-morbidity, QoL (according to the SF-36 index) and analytical values to calculate the oxidative related Fibrosis-4 (FIB-4) index were recorded. The association between FIB-4 and co-morbidity, antioxidant habits in QoL was assessed in univariate analysis (p p p < 0.01). Liver fibrosis assessed by the oxidative surrogate index FIB-4 is associated with the interaction between antioxidant lifestyle, co-morbidity and physical, social and general aspects of QoL in apparent liver disease-free individuals, generating a proof of concept for health empowerment and personalized medicine.