This article presents evidence of a “Latino oral health paradox,” in which Mexican immigrant parents in California's Central Valley report having had better oral health status as children in Mexico than their U.S.-born children. Yet little research has explored the specific environmental, social, and cultural factors that mediate the much-discussed “Latino health paradox,” in which foreign-born Latinos paradoxically enjoy better health status than their children, U.S.-born Latinos, and whites. Through ethnography, we explore the dietary and environmental factors that ameliorated immigrant parents’ oral health status in rural Mexico, while ill preparing them for the more cariogenic diets and environments their children face in the United States. We argue that studies on the “Latino health paradox” neglect a binational analysis, ignoring the different health status of Latino populations in their sending countries. We use the issue of immigrant children's high incidence of oral disease to initiate a fuller dialogue between U.S.-based studies of the “health paradox” and non-U.S.-based studies of the “epidemiological transition.” We show that both models rely on a static opposition between “traditional” and “modern” health practices, and argue that a binational analysis of the processes that affect immigrant children's health can help redress the shortcomings of epidemiological generalizations.