Sir,We read with great interest the recently published article by Ergül et al.[1] They aimed to show the beneficial effect of chewing gum on colonoscopy preparation and found enhancement in bowel preparation quality with gum chewing. We thank Ergul et al. for this valuable evaluation, but there are several issues that need to be clarified for a better understanding of the results presented in the authors’ report.The authors found more effective cleaning with sugarless gum in their study. But the ingredients of the gums used were not defined. Most of the sugarless gums contain sweeteners such as sorbitol, xylitol, and aspartame. Sorbitol is poorly absorbed by the gut, and as such acts as an osmotic agent. Sorbitol has been shown to induce osmotic diarrhea at high doses, but its effect at low doses is still controversial.[23] Sorbitol, even in low doses, might have additive effect on bowel cleaning. Although there are different sweeteners in chewing gums, most of them still contain sorbitol in Turkey where the study originated. Thus, in this study the ingredient of the gum could have been mentioned.Although chewing gum is a cheaper and simple method, which can be used before colonoscopy preparation, but the value of utilizing this must be interpreted with caution until the ingredients of the gum are further clarified.