The present invention relates to the field of metabolic research. Metabolic disorders, such as obesity, are a public health problem that is serious and widespread. GZIP polypeptides have been identified that are believed to be beneficial in the treatment of metabolic disorders. These compounds should be effective for reducing body mass and for treating metabolic-related diseases and disorders. These metabolic-related diseases and disorders include hyperlipidemias, atherosclerosis, diabetes, and hypertension.