New preclinical research published in Cell Reports Medicine suggests that bowel preparation for colonoscopy may temporarily disrupt gut balance, potentially increasing susceptibility to infection and inflammation in individuals with compromised gastrointestinal health.
In mouse models, researchers simulated bowel preparation using polyethylene glycol (PEG), a common laxative ingredient. The treatment caused diarrhea, temporarily depleted the gut’s protective mucus barrier, reduced beneficial gut bacteria, and lowered levels of short-chain fatty acids that help protect against infection and inflammation. Although the mice recovered within a few days, this period created a window of weakened gut defenses.