Study Explores Gut Microbiome Recovery Following Colonoscopy at Mizzou

The gut microbiome comprises diverse microorganisms that play an essential role in human health, with alterations in its composition linked to several chronic conditions, including obesity, type 2 diabetes, inflammatory bowel disease, and cardiovascular disease.

Katherene Osei-Boadi Anguah, an assistant professor in nutrition and exercise physiology, noted that the preparation for colonoscopy effectively clears much of the gut microbiome. This absence provides a unique opportunity to study how the microbiome regrows and how diet—particularly dietary fiber—affects this process.

In collaboration with colleagues from the School of Medicine, College of Veterinary Medicine, and MU Health Care, Anguah's team recruited patients scheduled for routine colonoscopies, ensuring they had no prior gastrointestinal issues. The researchers monitored the gut microbiome before the procedure and again two weeks post-colonoscopy. Participants maintained detailed food intake logs, collected both pre- and post-procedure, to track their eating habits.

The results showed that approximately 70% of beneficial microorganisms were lost three days after the colonoscopy, with some recovery observed by day five. Notably, participants experienced a reduction in energy levels the day before the colonoscopy due to an all-liquid diet, followed by increased food consumption afterward to offset their caloric deficit.

The types of food consumed post-procedure, particularly the amount and timing of fiber intake, influenced the speed of microbiome recovery. While participants’ fiber intake was initially above the average American level, it decreased significantly on the day of the colonoscopy but returned to baseline by the second day post-procedure. The findings indicate that at least two days of normal eating are necessary to restore the gut microbiome after the disturbance caused by colonoscopy prep.

Anguah highlighted the correlation between microbiome diversity and fiber intake, noting that recovery aligned with the return of fiber consumption to pre-procedure levels. Additionally, the unexpected rise in certain pathogenic bacteria post-colonoscopy raises concerns about the increased risk of harmful bacteria proliferation following gut disruption.

These findings set the groundwork for future research aimed at enhancing dietary recommendations from dietitians and gastroenterologists. Anguah expressed interest in investigating whether fiber intervention could support gut microbiome recovery and mitigate the effects of pathogenic bacteria observed in their study.

The research, titled "Repopulation of the gut microbiota after a screening colonoscopy," was published in PLOS One, with contributions from Aaron Ericsson, Jennifer Anderson, Jessica George, Elizabeth Parks, and Yezaz Ghouri.