Use of Beetroot Juice to Protect Against Postoperative Ileus (POI) Following Colorectal Surgery: a Pilot Study.

Inclusion Criteria: • All patients undergoing colonic or upper rectum laparoscopic surgery. Exclusion Criteria: * Pregnancy or breast feeding * Psychiatric pathology capable of affecting comprehension and judgment faculty * History of metastatic disease * History of prior abdominal bowel surgery * Abdominal radiation treatment * Chronic constipation (defined as two or fewer bowel movements per week) * Gut motility influencing agents (e.g. tricyclic antidepressants, chronic use of laxatives) * Frequent use of mouthwash, as this affects the enterosalivary circulation of nitrate * Current use of broad-spectrum antibiotics, which will affect the oral flora and likely affect the nitrate reductase activity * More than one bowel anastomosis during this surgery