The document proposes a diagnostic chewing gum for identifying the presence of inflammatory tissues in the mouth, in particular in or adjacent to the mandible, the maxilla, an implant or the teeth of a user, comprising a base material or particles (3) embedded and/or attached to the base material; an element (1, 5-7), like e.g. a releasable flavor molecule, attached to the base material and/or the particles, for the generation of a change in the chewing gum directly detectable by the user; wherein the element (1, 5-7) generates the change upon direct or indirect contact with a marker (4), e.g. a proteolytic enzyme, which is released by inflammatory tissue in response to bacterial mediators.