The BacterioPHAGE for Gastrointestinal Health-2 study is designed to determine if a commercial bacteriophage product can increase the survival and efficacy of probiotic bacteria that will be concurrently administered. Bacteriophages may act as prebiotics, which are traditionally defined as indigestible dietary components that selectively enhance specific bacterial species in the intestines to confer a health benefit. In this study, the "prebiotic" is a unique combination of bacteriophages, or viruses that infect bacteria. These phages are generally regarded as safe for human consumption and are presumed to function by infecting pro-inflammatory E. coli strains in the gut. The removal of these strains alters the gut environment to allow growth of more favorable bacteria, and the lysis products of these E. coli may be assimilated by beneficial species to enhance their populations.The phage product, PreforPro, has shown to be effective in culture-based and animal studies, but its efficacy in increasing specific probiotic species has not been demonstrated in humans. The investigators have previously shown that PreforPro is both safe and tolerable in a human population and does not broadly disrupt the gut microbiota as would be seen with antibiotic treatment.