Dietary fiber is a critical component of nutritional therapy for gastrointestinal (GI) disorders and is increasingly recognized as a therapeutic adjunct. This review summarizes recent evidence (2020– 2024) on fiber intake in inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and di- verticular disease, based on a literature review of clinical studies, meta-analyses, and guidelines. In IBD, high-fiber diets have shown beneficial effects with differences between Crohn’s disease (CD) and ulcerative colitis (UC). A recent meta-analysis in CD found that high fiber intake is safe and associated with prolonged remission, although some CD patients report fiber-related symptom exac- erbation. In UC, fiber-rich diets (especially soluble fiber) have been linked to reduced inflammation and sustained remission (for example, a low-fat, high-fiber diet improved quality of life in UC patients in remission). In IBS, soluble fiber (e.g., psyllium) significantly alleviates symptoms, particularly in constipation-predominant IBS, whereas insoluble fiber is often ineffective or poorly tolerated. For diverticular disease, high fiber intake remains a mainstay of therapy: guidelines recommend gradually increasing fiber to reduce symptoms and prevent diverticulitis, and recent studies associate high fiber diets with lower diverticulitis risk. In conclusion, dietary fiber is a valuable component of nutritional therapy across these gastrointestinal conditions, but its role is nuanced. Tailoring the type and amount of fiber to the specific disease (e.g., CD vs UC) and individual tolerance is crucial to maximize ben- efits and minimize adverse effects