Food or beverage where fucoidan which is derived from a fucoidan-containing substance is contained therein, added thereto and/or diluted therein. Food or beverage where fucoidan which is derived from a fucoidan-containing substance and where algins are reduced or eliminated, is contained therein. Apoptosis-inducing food or beverage where an effective amount of fucoidan having an apoptosis-inducing ability is contained therein.