The notion of food security has an important history as a key concept for 20th‐century policymakers. Two overarching perspectives on food security are identified. One centred on raising production as the core answer to under‐consumption and hunger. The other is an emerging perspective, more social and ecological, accepting the need to address a complex array of problems, not just production. The first is primarily agricultural‐focused; the latter a food systems approach. From its inception in post‐World War 2 international reconstruction, the UN and governments have given tackling hunger a high profile, via a changing package of policy measures. Within a few decades, the production‐oriented approach or paradigm was being questioned by the emerging paradigm with its more complex, multi‐focused notion of the challenges ahead. When oil and agricultural commodity prices spiked in 2007–8, the complex agenda was marginalised by a renewed international focus on primary production and the needs of low‐income countries. Against this background, the paper explores the diversity of perspectives on what is meant by food security, concluding that the core 21st‐century task is to create a sustainable food system. This requires a more coherent policy framework than currently exists, a goal thwarted by competing solutions vying for policy attention and policy failure thus far to integrate the complex range of evidence from social as well as environmental and economic sources into an integrated policy response.

This paper summarizes the main findings of the GLAMUR project which starts with an apparently simple question: is “local” more sustainable than “global”? Sustainability assessment is framed within a post-normal science perspective, advocating the integration of public deliberation and scientific research. The assessment spans 39 local, intermediate and global supply chain case studies across different commodities and countries. Assessment criteria cover environmental, economic, social, health and ethical sustainability dimensions. A closer view of the food system demonstrates a highly dynamic local–global continuum where actors, while adapting to a changing environment, establish multiple relations and animate several chain configurations. The evidence suggests caution when comparing “local” and “global” chains, especially when using the outcomes of the comparison in decision-making. Supply chains are analytical constructs that necessarily—and arbitrarily—are confined by system boundaries, isolating a set of elements from an interconnected whole. Even consolidated approaches, such as Life Cycle Assessment (LCA), assess only a part of sustainability attributes, and the interpretation may be controversial. Many sustainability attributes are not yet measurable and “hard” methodologies need to be complemented by “soft” methodologies which are at least able to identify critical issues and trade-offs. Aware of these limitations, our research shows that comparing local and global chains, with the necessary caution, can help overcome a priori positions that so far have characterized the debate between “localists” and “globalists”. At firm level, comparison between “local” and “global” chains could be useful to identify best practices, benchmarks, critical points, and errors to avoid. As sustainability is not a status to achieve, but a never-ending process, comparison and deliberation can be the basis of a “reflexive governance” of food chains.

Public health thinking requires an overhaul. Tim Lang and Geof Rayner outline five models and traditions, and argue that ecological public health—which integrates the material, biological, social, and cultural aspects of public health—is the way forward for the 21st century

It is well known that food has a considerable environmental impact. Less attention has been given to mapping and analysing the emergence of policy responses. This paper contributes to that process. It summarises emerging policy development on nutrition and sustainability, and explores difficulties in their integration. The paper describes some policy thinking at national, European and international levels of governance. It points to the existence of particular policy hotspots such as meat and dairy, sustainable diets and waste. Understanding the environmental impact of food systems challenges nutrition science to draw upon traditions of thinking which have recently been fragmented. These perspectives (life sciences, social and environmental) are all required if policy engagement and clarification is to occur. Sustainability issues offer opportunities for nutrition science and scientists to play a more central role in the policy analysis of future food systems. The task of revising current nutrition policy advice to become sustainable diet advice needs to begin at national and international levels.