Abstract: The present invention relates to methods for inhibiting sebaceous gland activity in mammalian skin comprising administration of a topical composition comprising dehydroacetic acid or pharmaceutically acceptable salts thereof, and a dermatologically-acceptable carrier. The present invention also relates to methods and topical compositions further comprising agents which regulate the oily and/or shiny appearance of skin, and agents which treat acne and related skin disorders in mammalian skin and scalp. Methods of reducing sebum synthesis with the use of dehydroacetic acid, methods of regulating the oily and/or shiny appearance of skin, and methods of treating acne and other skin disorders are also encompassed by the present invention.