Health claims and observational human data: relation between dietary fat and cancer

The US Food and Drug Administration review that provided the basis for authorizing a food-label health claim linking the risk of cancer to dietary fat intake illustrated several considerations in the use of epidemiologic data, and observational data in particular, to support dietary recommendations. The review suggested the need for clear and established criteria for judging the quality of observational human data as well as the importance of making the evaluation process for individual studies transparent and organized. The review, which provided for a claim in the absence of controlled human studies, also suggested that observational data may play a greater role when the nature of the relation to be described by a health-claim statement is broad and general rather than targeted and specific. Of particular importance was the relevance of available data to the questions inherent in showing a diet-disease relation, the need to consider the totality of the evidence, and the key role that existing authoritative reports must play in establishing the basis for relation.