The present invention provides a composition (e.g., a pharmaceutical composition) comprising at least one delivery agent compound and at least one of peptide YY (PYY) and a PYY agonist. Preferably, the composition includes a therapeutically effective amount of peptide YY or the PYY agonist and the delivery agent compound. The composition of the present invention facilitates the delivery of PYY, a PYY agonist, or a mixture thereof and increases its bioavailability compared to administration without the delivery agent compound. PPY and PYY agonists possess activity as agents to reduce nutrient availability, including reduction of food intake.