Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies was asked to provide a scientific opinion on a health claim pursuant to Article 13 of Regulation (EC) No 1924/2006 in the framework of further assessment related to a combination of Propionibacterium freudenreichii SI 41and Propionibacterium freudenreichii SI 26 and increasing numbers of gastro-intestinal microorganisms. The food constituent that is the subject of the health claim, a combination of Propionibacterium freudenreichii SI 41and Propionibacterium freudenreichii SI 26, is sufficiently characterised. The claimed effect proposed for further assessment is “beneficially affects the intestinal flora by increasing bifidobacteria”. The proposed target population is the general population. The evidence provided does not establish that the proposed claimed effect, increasing numbers of gastro-intestinal microorganisms, is a beneficial physiological effect. The Panel concludes that a cause and effect relationship has not been established between the consumption of a combination of Propionibacterium freudenreichii SI 41 and Propionibacterium freudenreichii SI 26 and a beneficial physiological effect related to increasing numbers of gastro-intestinal microorganisms.