Scientific evaluation of traditional Chinese medicine under DSHEA: a conundrum. Dietary Supplement Health and Education Act.

In the United States, traditional Chinese medicines (TCM) are currently sold as dietary supplements, as defined by The Dietary Supplement Health and Education Act (DSHEA). This legislation is unique to the United States and while "structure and function" claims are allowable under DSHEA, disease claims are not. The narrow definition, however, poses a challenge to designing appropriate clinical studies that can provide data for "structure and function" claim substantiation. The process of melding Chinese herbal medicines into the dietary supplement category is complex and there is a need to define a clinical trial paradigm carefully that addresses "structure and function claims" without sacrificing scientific rigor. It is frequently not recognized that TCM favors an amalgamation of several herbs to generate the putative clinical effect. Because of this historical multiherb approach, the reliance on retrospective data to support the potential health benefits of an herb extract has severe limitations. Notwithstanding the immense value of identifying the pharmacological activity of a TCM herb to a chemical suitable for pharmaceutical development, another approach to safe and efficacious herbal products is to develop a standardized herbal extract. This article highlights issues related to the latter approach and will discuss a research-based strategy that may be suitable for validating, in part, the putative health benefits of TCM.