Interestingly, Cyp2e1-null-FF mice exhibited overall higher TEE, increased ambulatory activity, and fatty acid oxidation efficiency than their WT-FF counterparts (S-Figs 4–6), probably explaining the underlying reasons for the leaner Cyp2e1-null-FF mice with lower body weight gain and hepatic steatosis. Here, CYP2E1 is linked to fatty liver disease.