Soybeans have desirable nutritional properties, since they contain about twice the protein of other legumes per serving. Some soybean protein ingredients have protein digestibility corrected amino acid scores commensurate with proteins thought to be optimal to meet human protein needs. This chapter examines recent human clinical studies related to the efficacy and safety of soybean foods and food or dietary supplement ingredients including soybean oils, proteins, isoflavones and selected other compounds for which soybeans are a significant source.