“The GI tract is a major endocrine organ,” says Sean Adams, professor and scientific director, Center for Alimentary and Metabolic Science at UC Davis. “Many of the cells secrete hormones which are relevant to food intake regulation, energy expenditure, gastric emptying, gastric motility. Nutrients and metabolites can trigger these cells to produce native GLP-1, peptide YY (PYY), Glucose-dependent insulinotropic polypeptide (GIP) and Cholesystokinin.”
While these hormones rise after a meal, the hormone ghrelin falls. “A meal has the opposite effect with ghrelin,” says Adams. “It’s actually reduced following a meal. Most people believe it’s a hunger-regulating hormone. I don’t believe it. I think it’s more of a glucose regulatory hormone. PYY and GLP-1 go back and interact with ghrelin. In short ,these hormones regulate each other.”
