Our aim is to shed light on the relationships between research, knowledge, and policy in the case of goitre and the use of iodine as a preventive measure against it in Norway from the 1850s onward. Goitre was previously widespread in certain areas of Norway, but disappeared around 1950. After many decades of silence about goitre and iodine, an expert report in 2016 argued that action should be taken to prevent iodine deficiency. Already in 1927, an international conference on goitre led to the agreement that the best preventive measure against goitre was to fortify table salt with iodine. The conference had Norwegian participants, but Norwegian health authorities did not follow the recommendations from the conference. To understand why new knowledge and recommendations did not result in new policy, we explore the history of Norwegian research on goitre and iodine, and Norwegian contributions to and the inspiration from international research in the field. Furthermore, we analyse the measures for the prevention and curing of goitre that have been implemented by authorities over time. The preventive measures introduced in Norway from the 1930s were very modest and differed from those in other countries. We argue for the importance of analysing the political context to understand the success or failure of advice given by researchers to policymakers.