Review of Evidence In Support of Health Claims
What are health claims?
Health claims on food labels provide information to consumers to help reduce their risk of disease, and are one of the ways they receive scientifically valid information about the foods they eat. A health claim for a food describes the relationship between a food or food component and a disease or health-related condition, and is limited to claims about disease risk reduction. Claims about the cure, mitigation treatment or prevention of disease are considered to be drug claims.
Unqualified and qualified health claims
In the U.S., oversight for determining which health claims may be used in food labeling is through the Food and Drug Administration (FDA). For authorized health claims (also referred to as unqualified), FDA issues a regulation authorizing a health claim that meets the scientific standard as stated in the 1990 Nutrition Labeling and Education Act (NLEA). These claims are based on evidence that constitute “significant scientific agreement” (SSA) and are based on a high level of confidence in the disease-substance relationship from systematic review of the literature. An example is “Diets low in saturated fat and cholesterol, and rich in fruits, vegetables and grain products that contain certain types of dietary fiber may reduce the risk of heart disease, a disease affected by many factors”.
When the strength of the scientific evidence for a health claim falls below that required for authorizing a claim, the FDA may issue a letter of enforcement discretion for qualified health claims (QHC) as provided by FDA Consumer Health Information for Better Nutrition Initiative in 2003. These types of health claims must be qualified to ensure clear and accurate presentation of information to consumers.
The goal of the review process for QHCs is to stimulate the flow of meaningful, up-to-date information to consumers about the health consequences of their dietary choices, and to stimulate competition among food producers to improve the healthfulness of their products.
Review process for health claims
The process for review of the scientific evidence begins with identification and classification of relevant studies suitable for an evidence-based review: randomized controlled clinical trial (RCT), observational, research synthesis studies such as meta-analyses, or animal/in-vitro studies. Human studies should be used to support a health claim. Animal and in vitro studies are considered useful, but are not sufficient on their own to substantiate a claim. Meta-analysis studies and review articles can help to identify studies to be examined. The RCT is considered the “gold standard”; however, it is not always possible or feasible to conduct such studies on food and food components. Thus, the available studies are generally observational, which, although less persuasive, are reviewed for their relevance to support the claim, with consideration of control for confounders and bias, appropriateness of the study population, the validity of the measurements used, and soundness of the experimental design and analysis. The strength of the evidence to support the claim is evaluated based on the quality of the studies, the consistency of results, and the relevance to the asserted health claim relationship.
A QHC is distinguished from an SSA claim by language that characterizes the quality and strength of the scientific evidence. For a QHC to appear on a food product, the claim must go through the FDA review process, which may include an expert evaluation of the supporting scientific evidence for the claim and how accurately the language included in the claim conveys the scientific evidence supporting it. A four point scale is used to evaluate and classify the scientific evidence in support of a health claim:
A: Unqualified (authorized) health claims are supported by evidence that meets the current standard of “significant scientific agreement.”
B: QHC includes such qualifying language as “although there is scientific evidence supporting the claim, the evidence is not conclusive”.
C: QHC includes qualifying language as “evidence is limited and not conclusive”.
D: QHC contains qualifying language such as “very limited and preliminary scientific research suggests that FDA concludes that there is little scientific evidence to support this claim”.
Detailed information about the review process can be found at:
Information for this article was obtained from:
Schneeman, B. “FDA’s Review of Scientific Evidence for Health Claims” Journal of Nutrition. 137:493-94, 2007
“Dear Manufacturer Letter Regarding Food Labeling”
“FDA implement enhanced regulatory process to encourage science-based labeling and competition for healthier dietary choices” http://www.cfsan.fda.gov/~dms/nuttfbg.html
“Guidance for Industry: Significant Scientific Agreement in the Review of Health Claims for Conventional Foods and Dietary Supplements” http://www.cfsan.fda.gov/~dms/ssaguide.html