Efficacy of PosBion® Postbiotic Supplementation in Adults With Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by recurrent abdominal pain and altered bowel habits, often associated with impaired intestinal barrier function, low-grade inflammation, and dysregulation of the gut-brain axis. Postbiotics have emerged as a promising therapeutic approach due to their immunomodulatory, anti-inflammatory, and gut barrier-protective properties. This completed single-arm, open-label clinical study evaluated the efficacy of PosBion® postbiotic supplementation in adults with IBS over a 12-week intervention period. The study assessed changes in IBS symptom severity, quality of life, gastrointestinal health, inflammatory biomarkers, intestinal barrier integrity, mucosal immunity, oxidative stress, and gut-brain axis biomarkers using validated questionnaires and salivary biomarker analyses.

Inclusion Criteria: * Experienced one or more symptoms consistent with irritable bowel syndrome (IBS), including: * Stomach pain or abdominal cramps * Bloating * Excessive gas * Diarrhoea * Constipation (or alternating diarrhoea and constipation) * Mucus in stool * Urgency to defecate * Sensation of incomplete bowel evacuation * Willing and able to comply with all study procedures and scheduled visits. * Provided written informed consent before study participation. Exclusion Criteria: * History of chronic or serious medical conditions, including but not limited to diabetes mellitus, cardiovascular disease, chronic kidney disease, cancer, or chronic respiratory disease. * Current use of supplements intended to improve gut health. * Current use of antibiotics or antiviral medications. * Current use of probiotic, prebiotic, or postbiotic supplements. * Major surgery within the previous 6 months. * Pregnant or breastfeeding women. * Known allergy or hypersensitivity to any ingredient of the investigational product. * Any condition that, in the opinion of the investigators, could interfere with study participation, compliance, or interpretation of the study results.