The present invention relates to novel Pancreatic Polypeptide Family ("PPF") polypeptides. The PPF polypeptides of the invention generally include at least two PPF motif, have at least 50 % sequence identity to PYY (3-36) over its length and will generally retain, at least in part, a biological activity of a PP, PYY or NPY Preferred PPF polypeptides of the invention are those having a potency in one of the assays described herein (preferably food intake, gastric emptying, pancreatic secretion, or weight reduction assays) which is greater than the potency of PP, NPY, PYY, or PYY(3-36) in that same assay. In one aspect, the PPF polypeptides of the invention include novel PYY analog polypeptides. In another aspect, the PPF polypeptides of the invention include PPF chimeric polypeptides including a fragment of a PP family polypeptide linked to a second PP family polypeptide, wherein each of the first and second fragments includes a PPF motif. Methods of using the PPF polypeptides of the invention, and pharmaceutical compositions including the PPF polypeptides of the invention are also disclosed.