The purpose of the present invention is to provide a highly safe agent for enhancing the whitening effect of a whitening ingredient and a whitening agent, said whitening agent comprising a whitening ingredient together with the aforesaid agent for enhancing the whitening effect thereof and having an improved and enhanced whitening effect. Provided is an agent for enhancing whitening effect which comprises, as the active ingredient, one or more members selected from guanine and analogs thereof. Also provided is a whitening agent which comprises the aforesaid agent for enhancing whitening effect together with a whitening ingredient, in particular, one or more members selected from adenine and analogs thereof and/or equol and analogs thereof.本發明係提供一種強化美白成分之美白作用,且具優異安全性之美白強化劑,並以提供併用如此之美白強化劑與美白成分而成之改善美白作用,且經強化之美白劑為課題,本發明之解決方式係提供含有1種或2種以上選自鳥嘌呤類作為有效成分之美白強化劑,以及由併用如此之美白強化劑與美白成分,特別是1種或2種以上選自腺嘌呤類及/或雌馬酚(Equol)類而成之美白劑。
