Disclosed are oral care compositions and the use of such oral care compositions for treating or preventing oral malodor. Also disclosed are methods for treatment or prevention of oral malodor. The oral care compositions include serine in an amount effective to reduce oral malodor caused by hydrogen sulfide and/or indole.揭示口腔保健組成物以及此類口腔保健組成物於治療或預防口臭之用途。亦揭示用於治療或預防口臭的方法。該口腔保健組成物含有有效降低硫化氫及/或吲哚所導致之口臭的絲胺酸含量。