Inclusion Criteria:  Adult patients undergoing elective colonic and upper rectum laparoscopic surgery requiring an anastomosis, without the need of conversion  Exclusion Criteria:  General:  < 18 years of age Pregnancy or breast feeding  Medical:  Psychiatric pathology capable of affecting comprehension and judgment faculty History of inflammatory bowel disease Chronic vascular disease affecting the intestines Chronic constipation (<= 2 bowel movements/week) Previous abdominal or pelvic radiation treatment Previous or current intra-abdominal infection or inflammation (e.g. diverticulitis, appendicitis) Use of gut motility influencing agents (e.g. tricyclic antidepressants, chronic use of laxatives) Use of nitrates (e.g. isosorbide dinitrate, nitroglycerin) Hypotension (< 100/60 mmHg) Uncontrolled diabetes mellitus Renal or hepatic insufficiency Known allergies or intolerances to beetroot, nitrates/nitrites Enrollment in other clinical trials/experiments, unless approved by the Ethics Committee(s)  Surgical:  History of prior colorectal surgery Emergency surgery Open surgery Colorectal surgery not requiring an anastomosis (e.g. colotomy, wedge resection) More than 1 bowel anastomosis planned Concomitant surgical procedures required (e.g. resection of liver or lung metastases) Protective stoma planned