Time-Restricted Eating and Symptom Severity in Irritable Bowel Syndrome: Results from a Pilot Study

Background/Objectives: Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder affecting approximately 5–10% of the population, with many individuals reporting insufficient improvement from treatment options. This study aimed to explore whether time-restricted eating (TRE) could alleviate symptoms in patients with IBS. Methods: This single-group, pre–post pilot study included participants with IBS who followed an 8-week time-restricted eating protocol, defined as a daily 16 h fasting period and an 8 h eating window (16:8). Symptom changes were assessed using the validated IBS Symptom Severity Scale (IBS-SSS) at baseline and post-intervention. The study was retrospectively registered after completion of data collection. Results: A total of 134 patients were enrolled, of whom 97 completed the intervention. Participants demonstrated a mean reduction in the IBS-SSS score of −100.2 (p < 0.001). Subgroup analysis also demonstrated mean reductions in the IBS-SSS scores for participants with IBS-constipation (IBS-C) (−125.2, p < 0.001), IBS-diarrhea (IBS-D) (−76.0, p < 0.005), and IBS-mixed (IBS-M) (−93.1, p < 0.001). Additionally, the participants experienced improvements in both self-reported physical and mental health. Conclusions: These preliminary findings suggest that TRE may represent a promising behavioral strategy for IBS symptom management, warranting controlled trials.