The Nourishing Britain study comprises 20 semi-structured interviews with UK prime ministers, health secretaries and other relevant senior ministers, as well as two regional mayors, all of whom who were in post or government between 1990 (when the first government obesity-reduction targets were being developed) and 2022 (the government before this project started). The larger aim of the project was to develop a political manual for current and future politicians on how to effectively navigate the politics of food-related health policy. The two overarching research questions the project sought to answer were: What barriers did senior politicians face in government when trying to pursue food-related health policies? And: What factors helped them overcome these?