The Impact of Sham Feeding with Chewing Gum on Postoperative Ileus Following Colorectal Surgery: a Meta-Analysis of Randomised Controlled Trials

J Gastrointest Surg. 2020 Nov;24(11):2643-2653. doi: 10.1007/s11605-019-04507-3. Epub 2020 Feb 26.


Background: Chewing gum as a form of sham feeding is an inexpensive and well-tolerated means of promoting gastrointestinal motility following major abdominal surgery. Although recognised by the Enhanced Recovery After Surgery (ERAS) Society as one of the multimodal approaches to expedite recovery after surgery, strong evidence to support its use in routine postoperative practice is lacking.

Methodology: A comprehensive literature review of all randomised controlled trials (RCTs) was performed in the Medline and Embase databases between 2000 and 2019. Studies were selected to compare the use of chewing gum versus standard care in the management of postoperative ileus (POI) in adults undergoing colorectal surgery. The primary outcome assessed was the incidence of POI. Secondary outcomes included time to passage of flatus, time to defecation, total length of hospital stay and mortality.

Results: Sixteen RCTs were included in the systematic review, of which ten (970 patients) were included in the meta-analysis. The incidence of POI was significantly reduced in patients utilising chewing gum compared to those having standard care (RR 0.55, 95% CI 0.39, 0.79, p = 0.0009). These patients also had a significant reduction in time to passage of flatus (WMD - 0.31, 95% CI - 0.36, - 0.26, p < 0.00001) and time to defecation (WMD - 0.47, 95% CI - 0.60, - 0.34, p < 0.00001), without significant differences in the total length of hospital stay or mortality.

Conclusion: The use of chewing gum after colorectal surgery is a safe and effective intervention in reducing the incidence of POI and merits routine use alongside other ERAS pathways in the postoperative setting.

Keywords: Chewing gum; Colorectal surgery; Postoperative ileus; Sham feeding.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Abdomen
  • Adult
  • Chewing Gum
  • Colorectal Surgery*
  • Gastrointestinal Motility
  • Humans
  • Ileus* / etiology
  • Ileus* / prevention & control
  • Length of Stay
  • Postoperative Complications / etiology
  • Postoperative Complications / prevention & control


  • Chewing Gum