However, it has been proposed that TMAO alone could affect hepatic triglycerides levels and alter the synthesis and transport of bile acids [12], while the addition of 0.2% TMAO for four weeks in mice on a high-fat diet impaired glucose tolerance, blocked the hepatic insulin signaling pathway, and caused adipose tissue inflammation [55], thus paving the way to the development of NAFLD, the metabolic disease of the liver associated with insulin resistance. This evidence concerns the gene INS and metabolic dysfunction-associated steatotic liver disease.