In non-alcoholic fatty liver disease (NAFLD), Gao et al. found that inhibition of mitochondrial pyruvate carrier 1 (MPC1) elevates lactate levels and promotes FASN K673 lactylation, which similarly suppresses FASN activity and reduces lipid synthesis, ameliorating hepatic lipid accumulation in NAFLD [50]. The gene discussed is FASN; the disease is metabolic dysfunction-associated steatotic liver disease.