Impact of Dietary Fiber Supplementation on Colonic Microbiome

This study is testing whether adding dietary fiber supplements changes the types of bacteria living in the colon (the gut microbiome) in people undergoing a colonoscopy or minor surgery for benign colorectal conditions, with the goal of understanding how fiber shapes gut health. **You may be eligible if...** - You are 18 years or older - You are scheduled for a colonoscopy or minor surgery for a benign colorectal condition (such as hemorrhoids, anal fissures, or anal fistulas) - You are able to understand and sign a consent form **You may NOT be eligible if...** - You have colorectal cancer, Crohn's disease, ulcerative colitis, or a suppressed immune system - You have a hereditary colon cancer syndrome (like Lynch syndrome or FAP) - You have previously had part of your colon surgically removed - Colorectal cancer or proctitis is found during your scope Talk to your doctor to see if this trial is right for you.