A long and yet unfinished history of investigating how individual capabilities and social processes explain or predict health indicates that poor education, low literacy, poor health and early death are strongly linked around the world. However, the complexity of those relationships is not fully understood. In this article, we propose an expanded model of health literacy characterized by four domains: fundamental literacy (reading, writing, speaking and numeracy), science literacy, civic literacy and cultural literacy. To explore the utility of this model, we examine selected pieces of the public discourse about terrorism and bioterrorism that dominated the mass media during the anthrax threat in the United States during 2001. We conclude that this model of health literacy is useful to analyze health communication, to aid in constructing more understandable and appropriate health communication, and ultimately can lead to the development of a new measure to assess health literacy skills in individuals.