This study was designed as a pilot, open-labelled study. We enrolled consecutive IBS-M patients (n=25, 19 females, 46.06 ± 13.11 years) according to Rome IV criteria. Fecal samples were obtained from all patients twice (pre- and post-intervention) and high-throughput 16S rRNA sequencing was performed. Patients were divided into two groups based on age, gender and microbiome matched.

Six weeks of AI-based microbiome diet (n=14) for group 1 and standard IBS diet (Control group, n=11) for group 2 were followed. AI-based diet was designed based on optimizing a personalized nutritional strategy by an algorithm regarding individual gut microbiome features. An algorithm assessing an IBS index score using microbiome composition attempted to design the optimized diets based on modulating microbiome towards the healthy scores. Baseline and post-intervention IBS-SSS (symptom severity scale) scores and fecal microbiome analyses were compared.

Inclusion Criteria:

• Diagnosed with IBS by a medical doctor.
• BMI between 18.5-39.9 kg/m2
• No hospitalization in the last 12 months.
• No antibiotics use in the last 6 months.
• No cancer diagnosis by a medical doctor.
• No chronic complex diseases including diabetes and hypertension.

Exclusion Criteria:

• Not being diagnosed with IBS.
• Having a diagnosed chronic disease.
• Having a diagnosed mental or psychiatric disorder .
• Having endocrinal disorders.
• Being pregnant.
• Antibiotics use in the last 6 months.
• Hospitalization history in the last 12 months.
• Drug use.
• Being morbid obese.