Dimethylarginine dimethylaminohydrolase 1 (DDAH1), a key metabolizing enzyme for asymmetric dimethylarginine (ADMA), has been demonstrated to exert a protective effect in the pathogenesis of nonalcoholic fatty liver disease (NAFLD), yet its role in fasting-induced hepatic metabolic adaptation remains incompletely elucidated. This evidence concerns the gene DDAH1 and metabolic dysfunction-associated steatotic liver disease.