While the negative environmental, social and health impacts of the current food system have been acknowledged and evidenced for several decades, the recent and current transformations in food systems at diverse scales are not yet addressing the many inter-related stakes at play. Due to the much wider set of interactions in this consumption-production system, new conceptual tools are required for understanding and assessing sustainability transitions and what prevents them. The article will draw on the cases of France and the UK to examine these countries’ national food systems’ historical trajectories and suggest a periodization of these in order to reveal common characteristics and differences. This will show that despite common major trends and common transition or inertia mechanisms, pathways differ, especially from the 1990s, due to different configurations of power relationships between the state, economic actors and civil society in a context of an increasing competition between sustainability narratives that leads to an increasing fragmentation in food systems. It will lead us to join the recent progress in the sustainability transitions’ community towards a shift in the analysis from a focus on niches’ trajectories and effects to a deeper focus on power configurations and competing narratives, as well as to suggest a larger inclusion of socio-ecological and spatial dimensions.