β-galactosidase Producing Probiotic Strains to Improve Lactose Digestion

The trial will be cross over, randomized in incomplete blocks, controlled, double-blind:

each subject will be administered 3 products out of 4 (positive control, probiotic Streptococcus (S.) thermophilus, probiotic Bifidobacterium (B.) longum, negative control) in a random order on 3 different days separated by a washout period of at least one week, and maximum 2 weeks between each challenge.

The total sample size is 42 enrolled subjects/37 completed Patients will be males and females aged between 20 and 65 years with positive hydrogen breath test.

Inclusion criteria

• HBT> delta 20ppm (compared with the baseline value) measured at screening visit before challenge tests
• Having signed the informed consent or having provide his/her legal representative's informed consent

Exclusion criteria

• Known Food allergy
• Any obstructive (COPD, asthma…) or restrictive respiratory syndrome that may impact breath test measurements
• Any medically relevant malabsorption syndrome
• Any medically relevant chronic gut motility disorder other than Irritable Bowel Syndrome (IBS), assessed with Rome III questionnaire
• Ongoing therapy with drugs known to affect gut motility
• Any general antibiotherapy taken during or within 4 weeks of study onset
• Use of lactase pill (eg. Lacdigest®), as well as yoghurt and probiotics, for at least 2 days prior to Visit 0b
• Subject who cannot be expected to comply with the study procedures
• Currently participating or having participated in another clinical trial during last 8 weeks prior to the beginning of this study.
• To be a close collaborator to the Investigators, either in terms of Family relationship and/or professional relationship
• Pregnancy, based on anamnesis