vigilance, and risk management, and given the potential risk to the public entailed by serious adverse events, regulatory action can be justified on the basis of adverse event report analysis alone or as the predominant source of information. There is ample precedent for this approach from the realms of regulated medical products, such as drugs, biologics, and medical devices. Dietary supplements, as agents with biological activity, should be no exception.
Experience from generations of use by humans is often referred to as evidence of safety for modern dietary supplements that bear resemblance to substances used historically. Some botanicals, for example, have a long history of medicinal use in many cultures. It may be useful to consider that there is both ancient (thousands of years) and recent history (perhaps the last 100 years). Ancient history may include traditional Chinese, Ayurvedic, and Native American medicines. Information about the preparation and use of ancient remedies is more difficult to locate and verify.
Information about historical use is of less importance when relevant clinical, epidemiological, or animal toxicity data exist because if these types of data document harm, then this outweighs historical use that may show no harm. However, for many dietary supplement ingredients, the amount of scientific and experimental data are insufficient for a critical analysis of safety. Recognizing that a full range of data are unlikely to be available for many dietary supplement ingredients, historical use may be taken into account as a surrogate measure for safety in the absence of relevant scientific and experimental data. In doing so, it is important to consider the relevance of the traditional use to the current use and, as such, FDA must have information regarding both the traditional use and the current use to determine if the traditional use sheds any light on the potential risk associated with current use.
A starting place for obtaining information regarding traditional use of dietary supplement ingredients is secondary references. If secondary references suggest that the traditional use is similar to the current use and that the historical use has been without observed complications, then it is important to verify this information with primary sources before relying on it as even a weak surrogate indicator of safety. The quality of the original source of information should be considered before placing much value in secondary sources, as questionable information appears to be cited repeatedly, with problems in obtaining original information.