The Evidences Conveyed in Advertisements of Dietary Supplements in Health Magazines

Abstract

A large number of people take dietary supplements regularly in Taiwan. One of the reasons that people use dietary supplements might be because they are convinced by claims in advertisements about their health effects, particularly when the advertisements cite scientific research or evidence.The purpose of this study, therefore, was to investigate how the advertisements of dietary supplements conveyed claims of scientific evidence of health effects. Using quantitative and qualitative methods, this study analyzed 580 advertisements of dietary supplements in the top six health magazines in Taiwan from 2004 through 2006.The results show that five common categories of evidence cited in the advertisements were research, expert, certificate, statistics or graphs, and other unspecific evidence. The qualitative analysis show that the research cited in the advertisements was usually vague and biased. The experts who appeared were either pseudo-disinterested professionals who indirectly endorsed the products or overtly endorsers. Statistics in the advertisements were usually employed to increase the readers' fear about the health problems and then promote the product as a solution.The results of this study indicate that the evidence presented by the advertisements of dietary supplements seems to be convincing and plausible, but in fact the evidence is often ambiguous and distorted. This study suggests that there is a need to increase the public's media and scientific literacy in order to enable them to appropriately interpret and evaluate the research and evidence cited in such advertisements.