The present invention addresses the problem of providing: a novel composition for suppressing muscular fatty change, which contains a component that can be ingested safely for a long period； and others. It is found that quercetin or a glycoside thereof can suppress the process of the differentiation of a muscle satellite cell into an adipocyte-like cell. In the present invention, quercetin or a glycoside thereof is used in a composition for suppressing muscular fatty change and the like.
