Examination of lexical items in naturally occurring vernacular prose shows patterns of ambiguities in how Americans discuss health issues. Samples from the Freiburg–Brown corpus of American English and varied registers of popular health writing found online reveal two principles of naming beliefs that crosscut the uses of many ambiguous terms: the semantic principle of ‘lexical conflation’ and the semiotic principle of ‘edible iconicity’. Both are shown to reflect sources of nutritional conceptualizations. Lexical conflation is illustrated by uses of fat, cholesterol, sugar, oil, and germ, with modifiers shown to help disambiguate terms. Edible iconicity, where meaning is attached to the visible form of what is ingested and characteristics of a food are believed to transfer to the person who eats it, is illustrated through aspects of hard, white, and hot. Applications are suggested that take into account the influence on nutritional choices that can occur when lay people misinterpret specialized information as signifying a nonspecialist sense. Recognition of these two principles has the potential to affect public health policy by helping practitioners to identify and modify ambiguous words, and to take into account tendencies to interpret metaphors literally, especially regarding iconic ingredients and their presumed effect upon the body.