The purpose of this study is to evaluate the effectiveness of a mobile application (app) in helping clinicians and dietitians provide personalized low-FODMAP diet (LFD) therapy for patients with Irritable Bowel Syndrome (IBS). The study also aims to explore the potential biological mechanisms behind the clinical outcomes of this dietary intervention.

Participants diagnosed with IBS will be recruited and screened through clinical questionnaires. Eligible participants will receive dietary education from a dietitian and be randomly assigned to one of two groups: the AI-assisted LFDapp group or the LFD booklet group.

The study consists of three main phases:

Initial Intervention (4-6 weeks): Participants will follow their assigned diet intervention and complete assessments regarding gastrointestinal symptoms, psychological traits (such as anxiety and depression), and quality of life.

Reintroduction Phase (12 weeks): Participants who respond well to the diet will enter a phase where specific foods are gradually reintroduced.

Personalization & Follow-up (4 weeks): A personalized diet will be established, followed by a final evaluation of bowel function and mental well-being.

Researchers will use various standardized questionnaire to track changes in symptoms and overall well-being throughout the study period.

Inclusion Criteria:

• Participants aged between 20 and 65 years.
• Diagnosed with Irritable Bowel Syndrome (IBS)
• Overall IBS symptoms remain unresolved or active at the time of enrollment.

Exclusion Criteria:

• Inability to understand the study procedures or provide written informed consent.
• Currently pregnant.
• History of Inflammatory Bowel Disease (IBD).
• Active infection within the past 90 days.
• History of thyroid disease.
• Major psychiatric disorders, including patients with significant anxiety or depression currently requiring treatment with anti-anxiety or anti-depressant medications.
• History of epilepsy.
• History of stroke, cerebral hemorrhage, or other central nervous system diseases.
• Significant renal, hepatic, or major cardiovascular diseases.
• Malignant diseases (cancer).
• Type 2 diabetes.
• Other chronic pain conditions.
• History of abdominal surgery (excluding cholecystectomy or appendectomy) or any history of brain surgery.
• Appendectomy or cholecystectomy performed within the past year.
• Currently participating in other clinical trials.
• Use of antibiotics or analgesics within 90 days prior to enrollment.
• Newly initiated use of probiotics or prebiotics within 90 days prior to enrollment.
• Current use of antipsychotic medications, antidiarrheal agents, probiotics, or analgesics.

Randomly assigned in a 1:1 ratio to either the LFD app or LFD booklet group using a computer-generated random number table. The randomization sequence was sealed in opaque sealed envelopes, opened just before meeting the patients