BACKGROUND: Functional gastrointestinal disorders (FGIDs), now known as disorders of gut-brain interaction (DGBIs), such as Irritable Bowel Syndrome (IBS) and Functional Dyspepsia (FD), significantly impact global health, reducing quality of life and burdening healthcare systems. This study addresses the epidemiological gap in Poland, focusing on the West Pomeranian Voivodeship. METHODS: We conducted a cross-sectional study of 2070 Caucasian patients (58.2% female, mean age 57.5 ± 15.1 years) undergoing gastrointestinal endoscopic examinations at Pomeranian Medical University from 2021 to 2023. Data were collected using Rome IV diagnostic questionnaires and correlated with gastroduodenoscopy and colonoscopy findings. Exclusion criteria were age under 18, pregnancy, Crohn's disease, ulcerative colitis, severe comorbidities, cancer, immunosuppressive therapy, ileostomy/colostomy, incomplete questionnaires, or lack of consent. RESULTS: Using Rome IV criteria, IBS was diagnosed in 436 participants (21.1%) and FD in 248 participants (12.0%). Post-endoscopic evaluation revised FD diagnoses to 184 individuals (8.9%). Females had a higher prevalence of IBS and FD (OR 1.64 and 1.61, respectively). No significant association was found between higher BMI and increased risk of IBS and FD. Hypertension and diabetes prevalence were 35.1% and 13.0%, respectively. Individuals with a history of COVID-19 had a higher risk of developing IBS (OR 1.47, P = 0.050). CONCLUSIONS: Our study provides crucial epidemiological data on IBS and FD in Poland, emphasizing the importance of endoscopic evaluations. Our findings highlight the need for regional studies to understand local DGBI prevalence, aiding targeted healthcare strategies.