Título en inglés: Epistemic, institutional, and material assemblages of a public policy in health about coto in Colombia, 1935Colombia, -1970 This research is based on science and technology studies and cultural history to identify and explore the path through which coto was built as an object of scientific research and political and economic intervention during the XX century in Colombia, including the institutional and epistemic assemblages that lead to the establishment of public policies in health, the artificial iodization of salt in the country, its execution, and consequences. A specific study is made about the construction of the iodization policy in Colombia, between 1935-1955 in which we deal with the debates about the nature of the disease, the studies carried out to for its conceptualization and the campaigns that lead to the establishment of the Decree 591 of 1955, by which the iodization of all salt is decreed and regulated. We use the theories of coproduction and assemblage to build this narration in which we also highlight the processes of expertise building, the consolidation of a particular institutional structure and the standardization and quantification processes that make sense of the policy and the disease.