Herbal products and dietary supplements: a survey of use, attitudes, and knowledge among older adults.

Context: Tens of millions of Americans use herbal products and/or dietary supplements, yet scant data are available regarding the purity, safety, or efficacy of these substances. A better understanding of usage trends and patient attitudes toward self-initiated supplementation is vital to obtaining accurate and complete medical history data.

Objective: To survey Americans aged approximately 60 years and older regarding their use of herbal products and dietary supplements and their attitudes and knowledge regarding the safety of these popular substances.