NATURAL-PRODUCTS AND THE ATHLETE - FACTS AND FOLKLORE

OBJECTIVE: To contrast scientific facts with suggested manufacturers' claims regarding food supplements (natural products) marketed for enha nced athletic prowess. DATA SOURCES: A MEDLINE search was performed to obtain documentation supporting the claims of natural-product manufac turers. In addition, several references pertaining to pharmacognosy, n atural products, herbs, pharmacy practice, and sports medicine were re viewed. Claims were obtained from promotional advertisements in bodybu ilding magazines, product labels, and fact sheets for sales representa tives in nutrition and health-food stores. DATA EXTRACTION: We reviewe d all of the clinical trials, published between 1966 and 1992, relativ e to the manufacturers' claims regarding these products. DATA SYNTHESI S: Pertinent human and/or animal studies supporting each natural produ ct were compared with the manufacturers' claims. CONCLUSIONS: We found that there was no published scientific evidence to support the promot ional claims for a large proportion of the products (8/19,42 percent). Only 4 of 19 products (21 percent) were associated with any documente d human clinical trials supporting their promotional claims. Six of 19 agents (32 percent) had some scientific documentation to support thei r promotional claims; however, these products were judged to be market ed in a misleading manner.