This study aims to investigate the beneficial effects of the daily consumption of a synbiotic formulation-combining a prebiotic (Berberine, BBR) and a postbiotic (inactivated Bifidobacterium Longum, B.longum)-in adults experiencing intestinal discomfort.

This study is designed as a randomized double-blind placebo-controlled interventional study. One hundred and forty individuals aged between 18 and 75 years and experiencing a measurable level of intestinal discomfort will be randomly allocated to one of the four groups (35 subjects per group): control, prebiotic only, postbiotic only, or combination of both. Subjects will receive their assigned supplementation for 8 weeks. Intestinal discomfort will be measured through tests and questionnaires at baseline, mid-intervention (week 4), at the end of intervention (week 8), and after a follow-up period of 4 weeks (week 12).

Inclusion Criteria:

• Woman or man, aged of 18 to 75 years (inclusive);

• Subject with a measurable level of intestinal discomfort, assessed using a questionnaire inspired by the ROME IV criteria. Eligible participants must meet all of the following conditions:

  1. Experience recurrent abdominal pain present for at least three months and occurring on a regular basis;

  2. The abdominal discomfort must have a low to moderate impact on quality of life;

  3. In addition, participants must report at least two of the following gastrointestinal symptoms:

     • Diarrhea
     • Constipation
     • Bloating
     • Excessive flatulence
     • Nausea
     • Burping
     • Sensation of incomplete evacuation
     • Urgent need to defecate;

• Body Mass Index (BMI) between 18 and 30 kg/m² (inclusive);

• Provision of signed and dated informed consent form;

• Stated willingness to comply with all study procedures and availability for the duration of the study;

• Stated willingness to maintain their usual life habits (diet, physical activity, alcohol consumption…);

• Speaking French.

Exclusion Criteria:

• Subject with severe or chronic medical conditions which, in the opinion of the Principal Investigator, could interfere with the evaluation of the study outcomes or compromise participant safety;
• Subject with a diagnosed gastrointestinal disorder (e.g., Crohn's disease, inflammatory bowel disease, or other chronic digestive conditions);
• Subject with type 1 or type 2 diabetes;
• Subject who has taken, within the 28 days prior to the screening visit, or are currently taking, drugs or food supplements intended to improve intestinal comfort, or any other substances that, in the opinion of the Principal Investigator, could interfere with intestinal comfort assessment or transit frequency (prebiotics, laxative, anti-diarrheal, probiotics, postbiotics, synbiotics). These products will also be avoided for the duration of the study;
• Subject who has taken antibiotics within the 3 months prior to the screening visit. These products will also be avoided for the duration of the study;
• Subjects undergoing medical treatment which, in the opinion of the Principal Investigator, could interfere with the evaluation of the study criteria or with participant safety: antidepressants, immunosuppressants, antipsychotics, antispasmodics, anxiolytics, neuroleptics. These products will also be avoided for the duration of the study;
• Subject who had undergone bariatric surgery;
• Subject consuming more than 5 cups of coffee per day;
• Subject currently using drugs and/or with a history of drug addiction within the past 2 years;
• Subject with regular alcohol consumption exceeding 3 standard drinks per day (10 g of pure alcohol each), equivalent to 3 glasses of wine (12 cl), 3 glasses of beer (5°, 25cl), or 3 glasses of spirits (18°, 7 cl);
• Subject with known hypersensitivity to any component of the study product;
• Subject currently participating in another interventional trial;
• Woman of childbearing age who is pregnant or breastfeeding or who wishes to become pregnant within the next 12 weeks or who is not using an adequate method of contraception (e.g. oral contraception, IUD, abstinence, ...).