Abstract: A composition for inhibiting enamel demineralization, promoting enamel remineralization and/or increasing salivary secretory immunoglobulin A is disclosed. The composition may contain lithothamnium calcareum (LC). The composition may comprise a first solution comprising at least 0.01% by weight LC and a second solution comprising an amount of hydrochloric acid (HCL) sufficient to adjust the pH of the composition to a physiological pH. A method of inhibiting enamel demineralization and promoting enamel remineralization is also disclosed. The method may include exposing a tooth to a LC containing composition. The method may further include both topically and systemically exposing the tooth to an LC containing composition. A method of increasing salivary secretory Immunoglobulin A (SIgA) in a mammal is also disclosed. The method may include topically exposing an oral cavity to a LC containing composition.