Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies was asked to provide a scientific opinion on a list of health claims pursuant to Article 13 of Regulation (EC) No 1924/2006. This opinion addresses the scientific substantiation of health claims in relation to Lactobacillus rhamnosus ATCC 53103 (LGG) and "gastrointestinal health" and maintenance of tooth mineralisation. The scientific substantiation is based on the information provided by the Member States in the consolidated list of Article 13 health claims and references that EFSA has received from Member States or directly from stakeholders. The food constituent that is the subject of the health claims is L. rhamnosus ATCC 53103 (LGG). The Panel considers that L. rhamnosus ATCC 53103 (LGG) is sufficiently characterised. "Gastro-intestinal health" The claimed effect is "gastro-intestinal health". The target population is assumed to be the general population. The claimed effect is not sufficiently defined, and no further details were provided in the proposed wordings. The Panel notes that the references provided addressed several effects, and that it was not possible to establish the effect which is the target for the claim. The Panel considers that the claimed effect is general and non specific, and does not refer to any specific health claim as required by Regulation (EC) No 1924/2006. Maintenance of tooth mineralisation The claimed effect is "oral health/flora". The target population is assumed to be the general population. From the information provided, the Panel assumes that the claimed effect refers to the maintenance of tooth mineralisation by reducing mutans streptococci in the oral cavity. The Panel considers that maintenance of tooth mineralisation is a beneficial physiological effect. In weighing the evidence, the Panel took into account that the only human study provided from which conclusions could be drawn for the scientific substantiation of the claim did not show an effect of L. rhamnosus ATCC 53103 (LGG) consumption on reduction of dental caries at any site compared to placebo, the reduction of which could indicate an effect on maintenance of tooth mineralisation. On the basis of the data presented, the Panel concludes that a cause and effect relationship has not been established between the consumption of L. rhamnosus ATCC 53103 (LGG) and maintenance of tooth mineralisation.