What materials might be considered as dilutants or adulterants?

The reason that compounds which increase substance weight without enhancing efficacy are considered dilutants or adulterants is due to their effect on the quality and effectiveness of a substance, especially in the context of pharmaceuticals and dietary supplements. These compounds serve to alter the original product's composition, primarily by adding bulk or weight rather than contributing any beneficial properties or therapeutic effects.

Dilutants and adulterants typically compromise the integrity of a product, making it less effective, less safe, or more difficult to regulate. In pharmaceutical preparations, these unwarranted additions can dilute the active ingredients, potentially jeopardizing the expected outcomes for patients or consumers.

In contrast, nutritive supplements and flavoring agents may serve legitimate purposes that can enhance the user's experience or health benefits, while medicine ingredients are integral to the efficacy of a product. The focus of the question is specifically on materials that do not add value and dilute the primary substance instead. Hence, compounds that merely increase weight without providing positive effects fit this definition and are rightly categorized as dilutants or adulterants.