Study of Bacteria on Mood and Bowel Symptoms in Patients With Irritable Bowel Syndrome

Inclusion Criteria: * Diagnosis of Irritable Bowel Syndrome based on Rome III Criteria * Symptoms of mild to moderate anxiety and depression Exclusion Criteria: * Concurrent systemic disease and/or laboratory abnormalities considered by Investigators to be risky or that could interfere with data collection. * Concurrent organic Gastrointestinal (GI) pathology other than benign polyps, diverticulosis, hemorrhoids, lipomas and melanosis coli. * Psychiatric diagnosis other than anxiety or depression. * Patients treated with therapeutic/standard doses of antidepressants and/or anxiolytics * History of active cancer in the last 5 years, other than skin basal cells cancer * Pregnant or breastfeeding women * Treatment with antibiotics during the three months prior the study. * Known or suspected allergies to the study products (eg maltodextrin). * Patients who have heart pacemakers, metal implants, metal chips or clips in or around the eyeballs, artificial heart valves, metallic ear implants, bullet fragments or fixed brackets. * High fiber diet (\>35 g/day for males, \> 25 g/day for females), consumption of high inulin containing foods (\>5 g/day). * Consumption of any type of yoghurts or probiotic-containing products in the 4 weeks prior to the beginning of the study.