A component of a cigarette comprises a silver-based catalyst for the conversion of carbon monoxide to carbon dioxide. The silver-based catalyst comprises particles (e.g., nanoscale or larger sized particles) of metallic silver and/or silver oxide supported in and/or on metal oxide support particles. The silver-based catalyst can be incorporated into a cigarette component such as tobacco cut filler, cigarette paper and cigarette filter material to reduce the concentration of carbon monoxide in the mainstream smoke of a cigarette during smoking. The catalyst can also be used in non-cigarette applications.