2.1. Study Design and Participants
obesity, cancer
OBESITY, CANCER, LACTOSE INTOLERANCE, INFLAMMATORY BOWEL DISEASE
The present study was a randomized, double-blind, placebo-controlled pilot trial. We recruited healthy participants aged 40–65 years undergoing colonoscopy for screening or post-polypectomy surveillance. The exclusion criteria in our study were as follows: history of cancer, inflammatory bowel disease, lactose intolerance, or obesity (body mass index (BMI) > 30), and use of antibiotics, laxatives, metoclopramide, tegaserod, erythromycin, or proton-pump inhibitors within 1 month before colonoscopy. A study investigator explained in detail the aim and contents of the study to the participants and all subjects provided written informed consent. Information including age, sex, height, body weight, BMI, smoking and alcohol history, co-morbidities, the reason for a colonoscopy, previous colonoscopy experience, symptoms before colonoscopy, dietary habits, the number of defecations per day or week, and Bristol Stool Scale (BSS) were collected using a questionnaire. The study outline is summarized in 