Following an application from Tate & Lyle PLC submitted for authorisation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of the United Kingdom, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on thescientific substantiation of a health claim related to polydextrose and maintenance of normal defecation. The scope of the application was proposed to fall under a health claim based on newly developed scientific evidence. The food constituent that is the subject of the health claim is ‘polydextrose’. The Panel considers that polydextrose is sufficiently characterised. The claimed effectproposed by the applicant is ‘improved bowel function by increasing stool bulk’. The target population proposed by the applicant is ‘the general population’. The Panel considers that maintenance of normal defecation is a beneficial physiological effect. In weighing the evidence, the Panel took into accountthat, out of the three human intervention studies from which conclusions could be drawn for the scientific substantiation of the claim, one study showed an effect at doses of 20 g/day when polydextrose was given for 10 days, whereas two studies in which polydextrose was administered at doses of 21 and 18 g/day for longer periods of time did not show an effect. The Panel also took intoaccount that the evidence provided for the mechanisms by which polydextrose could contribute to the maintenance of normal defecation in vivo in humans is weak. The Panel concludes that a cause and effect relationship has not been established between the consumption of polydextrose and maintenance of normal defecation.