Studies have recently elucidated a link between certain prebiotics and lower perceived anxiety as well as biomarkers of stress. In this aim the investigators will explore the association between consumption of prebiotics and their relationship to perioperative anxiety / physiological stress response. The investigators hypothesize that subjects who receive prebiotics will have lower perioperative anxiety and stress versus control as measured by standardized surveys and biomarkers. Furthermore, the investigators hypothesize that lower anxiety will result in lower postoperative pain scores.