Following an application from Clasado Limited, submitted for authorisation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Malta, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to Bimuno® GOS and reducing gastro-intestinal discomfort.
The scope of the application was proposed to fall under a health claim based on newly developed scientific evidence. The application included a request for the protection of proprietary data.
The food constituent that is the subject of the health claim is Bimuno® GOS, a mixture of β-galacto-oligosaccharides, which is produced through conversion of lactose by enzymes from Bifidobacterium bifidum NCIMB 41171. The Panel considers that Bimuno® GOS is sufficiently characterised.
The claimed effect proposed by the applicant is “reduce bloating, flatulence and abdominal pain: these effects can be described collectively as abdominal discomfort”. The target population proposed by the applicant is the general adult population. Symptoms such as abdominal pain, cramp, bloating, straining, borborygmi (rumbling) and sensation of incomplete evacuation are associated with gastro-intestinal discomfort. Reducing gastro-intestinal discomfort is considered an indicator of improved gastro-intestinal function. Gastro-intestinal discomfort may be measured by using validated subjective global symptom severity questionnaires such as described in consensus opinions. The Panel considers that reducing gastro-intestinal discomfort is a beneficial physiological effect.
Following a literature search in PubMed, the applicant identified four human intervention studies and one review publication as being pertinent to the health claim. The applicant also provided two unpublished human intervention studies and three non-human studies for the scientific substantiation of the claim.
All the human and non-human studies provided by the applicant for this claim were already submitted in previous applications for the same claim, and which were assessed by the Panel with unfavourable outcomes, except for one unpublished human intervention study.
This multicentre, placebo-controlled, randomised, double-blind, parallel study investigated the effect of Bimuno® GOS on symptoms related to gastro-intestinal discomfort in subjects suffering from gastro-intestinal discomfort (bloating, flatulence, abdominal pain and/or need to defecate) in the past 12 months. Subjects who had a weekly average composite score of > 10 to questions on flatulence, “bowel moments” (difficulty, urgency, straining, sense of incomplete evacuation), abdominal pain and abdominal bloating in the week prior to randomisation were randomised to consume Bimuno® GOS (1.37 g/day; n = 208) or maltodextrin (n = 200) daily for four weeks. Participants completed on-line questionnaires on “bowel movements”, abdominal pain, bloating, flatulence, and stool consistency on a daily and/or weekly basis one week prior to the beginning of the study, during the four-week treatment period, and in the two-week follow-up period. At the end of the treatment and follow-up periods, participants also completed on-line “quality of life questionnaires”.
Upon a request by EFSA for clarification on the validation of the questionnaires used in the study to assess changes in gastro-intestinal symptoms during an intervention, and particularly in relation to their on-line use, the applicant referred to a consensus opinion and guidelines on the design of trials for functional gastro-intestinal disorders, and to a series of clinical trials on the efficacy of Tegaserod, a partial serotonin agonist, in treating symptoms of irritable bowel syndrome. However, the Panel considers that the evidence provided by the applicant did not establish that the on-line questionnaires used in the study to assess individual gastro-intestinal symptoms (abdominal pain, abdominal bloating, flatulence and “bowel movements”) have been validated to be integrated into an overall measure of functional gastro-intestinal discomfort. The Panel also notes that subjective global assessment of symptoms used to characterise the study population (flatulence, abdominal pain, abdominal bloating and bowel movement urgency) at baseline has been recommended as the primary outcome of efficacy (on which the main results should be based) for trials investigating functional gastro-intestinal disorders in the consensus opinion provided by the applicant and others published thereafter.
The Panel notes that the effect of Bimuno® GOS on the subjective global assessment of symptoms, a combined measure of efficacy which would indicate whether the intervention provided adequate relief of symptoms of gastro-intestinal discomfort, was not assessed, and that measures of individual gastro-intestinal symptoms through validated questionnaires may only be used as supportive evidence for the scientific substantiation of health claims on the reduction of gastro-intestinal discomfort. In addition, the Panel notes the reported effects of Bimuno® GOS on three out of the five individual outcomes investigated (i.e. abdominal pain, bloating and flatulence, but not in “bowel movements” or stool consistency) did not translate into a significant improvement of the subjects’ quality of life, which reveals inconsistency in the results. The Panel considers that this study does not provide information about the effect of Bimuno® GOS on relieving subjects from gastro-intestinal discomfort.
The Panel concludes that a cause and effect relationship has not been established between the consumption of Bimuno® GOS and reducing gastro-intestinal discomfort.