FDA regulates health claims in the labeling of food products under the Nutrition Labeling and Education Act of 1990. Health claims regulated by FDA meet significant scientific agreement (SSA) among experts that the diet-disease relationship purported by the health claim is supported by the totality of publicly available evidence. Health claims must also be “complete, truthful, and not misleading” and must ''enable the public to comprehend the information provided and to understand the relative significance of such information in the context of a total daily diet'' (21 CFR 101.14(c)-(d), 101.70).
In 2003, an FDA Task Force on Consumer Health Information for Better Nutrition issued recommendations for improving consumer understanding of the health consequences of their dietary choices. As part of the effort, the Task Force report provided guidance on an interim procedure and a review process for health claims that do not meet the SSA standard.1 These claims, referred to as qualified health claims (QHCs), are given qualifying language to distinguish the level of scientific evidence for the claim. One of the goals of this initiative was to allow manufacturers to communicate to consumers about emerging science related to diet and disease relationships.
In November 2005, FDA released Derby and Levy (2005) which reported the results of an experimental study of QHCs.2 The report revealed the difficulties of conveying to consumers information about the level of scientific evidence supporting the claim. The study tested four schemes, two with text sentences using adjectives to describe the level of evidence and two using report card grades (i.e., B, C, and D). The results indicated that text sentences were ineffective at conveying the intended level of evidence. The report card schemes helped consumers distinguish between various levels of scientific evidence. However, the schemes had unintended effects on respondents’ perceptions of scientific certainty relative to unqualified claims, such that respondents attributed higher levels of scientific evidence to certain QHCs bearing a grade of “B” than to non-graded SSA claims.
The Derby and Levy study examined hypothetical QHCs and used qualifying language similar to that recommended in the interim guidance to communicate the level of scientific evidence for a claim. Since that study took place, the FDA has allowed the use of several textual qualified health claims. The study described here examines four of those allowed QHCs and evaluates them against two approved SSA claims to determine the effectiveness of FDA’s current scheme for health claims and qualified health claims for conveying levels of scientific evidence supporting claims. The study also evaluates two alternative schemes for assisting consumers in distinguishing various levels of scientific evidence in an attempt to overcome some of the difficulties revealed by the earlier study. In addition, the study expands upon the first study by examining the impact of these claims and disclaimer schemes in the context of dietary supplements as well as foods.
1 See http://www.fda.gov/Food/LabelingNutrition/LabelClaims/QualifiedHealthClaims/ucm096010.htm
2 Derby, B. and A. Levy. 2005 Working Paper. “Effects of Strength of Science Disclaimers on the
Communication Impacts of Health Claims.”