The present invention relates to dietary supplementing methods useful for controlling obesity. More particularly, the invention relates to methods of administration of compositions containing defined chemical species useful for prevention and treatment of obesity. In a preferred embodiment, pharmaceutical compositions used in connection with the present invention comprise: (1) a zinc salt, (2) cyclo-Hispro and/or (3) arachidonic acid, and (4) at least one pharmaceutically acceptable excipient. More particularly, the invention relates to methods of manufacturing of preparing a soybean protein hydrolysate (SPH) comprising cyclo-Hispro.