Adèle Buckenmeyer, Nabil Nasri, and Daniela Cota (Cota team, INSERM U1215) have published a Spotlight article in Trends in Endocrinology & Metabolism, commenting on the work of Xiao et al. (Nature Metabolism, 2026). This study identified para-tyramine-O-sulfate (pTOS), a postprandial metabolite produced by the gut microbiota from dietary tyrosine, as a potent appetite suppressant in Burmese pythons. Acting on the ventromedial hypothalamus, pTOS also rises after meals in humans, though to a lesser extent. Notably, its postprandial increase is blunted in prediabetic and type 2 diabetic patients. The authors discuss the potential of this pathway as a therapeutic target in obesity, with possible advantages over current GLP-1-based treatments.