Numerous metabolites and derivatives of the intestinal microbiota, such as short-chain fatty acids, lipopolysaccharides, secondary bile acids, trimethylamine, imidazole propionic acid, branch chain amino acids, and indole, can act as messengers to influence a range of aspects, including host energy homeostasis, obesity, appetite, blood sugar regulation, insulin sensitivity, inflammation, and endocrine regulation, as well as to control host metabolism [24]. This evidence concerns the gene INS and obesity due to melanocortin 4 receptor deficiency.