Meta-Analysis Favors Low-Residue vs. Clear-Liquid Diet Before Colonoscopy

Clear liquids are still commonly used the day before colonoscopy, but in multiple randomized, controlled trials, patients allowed to eat a low-residue or fiber-free diet for one or more meals on the day prior to colonoscopy tolerated bowel preparation better than those on clear liquids and had comparable or better cleansing.

In a meta-analysis of nine studies with 1686 patients, a low-residue diet resulted in significantly better tolerability (odds ratio, 1.92) and willingness to repeat bowel preparation (OR, 1.86). The increased odds of an adequate bowel preparation (OR, 1.21) did not reach statistical significance, nor did the risk for adverse effects (OR, 0.88).