Functional foods are generally defined as foods that, due to their physiologically active substances, benefit health in addition to providing basic nourishment. As Brazilian legislation does not provide a definition for functional foods, the only possible actions is to claim that some foods have functional health proprieties. Based on a review of legislation, this paper discusses not only the lack of transparency in relation to the categories of products classified as foods and medicinal plants, but also the interactions and contradictions of functional food product legislation. Products may be classified either within the "New Food/or Ingredient category" or as "Bioactive Substances or Isolated Probiotics with Functional Properties and/ or Health Claims". Products such as garlic can also be classified into multiple food categories and as medicinal plants. Intersections in food legislation, especially with respect to functional and new food products, lead to misunderstandings and even omissions on the part of Brazilian National Sanitary Surveillance Agency (ANVISA). Moreover, health claims on food product labels can make distinction between foods and medicines difficult for consumers. In Brazil, clearer rules for the industry are necessary so that the consumer is not deceived by false cure promises.