DBRCT on the Effect of Wheat Polysaccharides on Common Cold Infections in Elderly

Inclusion Criteria: * men and postmenopausal women aged ≥ 50 * willingness to abstain as far as possible from food and supplements containing probiotics, prebiotic supplements, other fermented products, supplements containing vitamins and minerals as well as willingness to sustain a low dietary fibre diet for 14 weeks * written informed consent Exclusion Criteria: * subjects currently enrolled in another clinical study * subjects having finished another clinical study within the last 4 weeks before inclusion * surgery or intervention requiring general anaesthesia within 2 months before the study * current symptoms of common infectious diseases (CID) of the airways or other organ systems e.g. gastrointestinal tract * history of allergic rhinitis, allergic asthma, anaphylactic shock, quincke edema, food allergy (type I allergy) * allergy or hypersensitivity to any component of the test product (e. g. wheat, corn) * known congenital, acquired or iatrogenic immunodeficiency (e.g. HIV, chemotherapy, immunosuppression) * active autoimmune diseases * severe chronic disease (COPD, respiratory insufficiency, cancer, IBD, malabsorption, malnutrition, chronic inflammatory diseases, severe renal, hepatic or cardiac diseases) * known coeliac disease (gluten enteropathy) * chronic systemic or chronic topical treatment likely to interfere with evaluation of the study parameters: antiallergic drugs, antibiotics, intestinal or respiratory antiseptics, anti-rheumatics, antiphlogistics (except aspirin or equivalent products preventing from aggregation of platelets or blood clotting) and steroids prescribed in chronic inflammatory diseases (in the last 4 weeks before inclusion) * diabetes mellitus * other chronic treatments likely to interfere with study outcome: e.g. laxatives, body weight management and/or medication * chronic abdominal pain * bowel movement less than 3 times per week * subjects, who meet 2 or more Rome III criteria for constipation or who take laxatives on a regular basis * vegetarian, vegan diet * eating disorders (e.g. anorexia, bulimia) * alcohol and drug abuse * severe neurological, cognitive or psychiatric diseases * subjects not understanding or speaking fluently German * legal incapacity