GABA-fortified oolong tea s reduced leptin expression in epididymal adipose tissue and showed a protective effect on nonalcoholic fatty liver disease. It boosted lipid metabolism and promoted fatty acid oxidation. It also reduced lipogenesis-related protein levels of sterol regulatory element binding protein, acetyl-CoAcarboxylase, and fatty acid synthase and inhibited hepatic triglyceride levels. The gene discussed is FASN; the disease is metabolic dysfunction-associated steatotic liver disease.