Trans fats are defined by the Codex Alimentarius as unsaturated fatty acids containing at least a trans double bond. Industrially produced trans fats are formed in the course of the transformation through partial hydrogenation of liquid vegetable oils into semi-solid fats. They are amply used in the production of processed foodstuffs. In 2002, a FAO/WHO report presented convincing proof linking trans fat intake and the risk for developing cardiovascular disease, recommending that its daily consumption should not exceed 1% of total energy intake. Even before this milestone, several approaches had been pursued by government and public health organizations in different countries to reduce trans fat consumption. In Brazil, Anvisa’s 2003 resolution no360 established nutrition labeling of the trans fat content mandatory from 2006. This thesis presents the evolution and analyses and assesses the regulatory processes for reducing trans fats in foodstuffs in Denmark, Canada, and the United States, seeking to identify lessons and best practices in their experiences to contrast with the Brazilian one. The thesis concludes by highlighting the role of metrology in qualifying health policy as well as other aspects derived from the analysis of the case studies. At the end, the study makes some recommendations for refining and improving Brazilian public policy actions and regulation addressing this issue.