LAUSR

Sustainable, resilient food systems for healthy diets has been identified as the first of the six pillars for action during theUN Decade of Action on Nutrition(1). It is now THE defining issue for public health nutrition(2). A sustainable food system is one ‘that ensures food security and nutrition for all in such a way that the economic, social and environmental bases to generate food security andnutrition of future generations are not compromised’(3) (p. 12). Resilience refers to the capacity of a food system to achieve this same objective ‘in the face of various and even unforeseen disturbances’ including environmental, economic or socio-political shocks(4) (p. 19). Sustainable food systems are essential if we are to nourish a projected global population of nearly 10 billion in 2050 within planetary boundaries(5). However, today’s food systems are far from sustainable. Not only are dietary risk factors and malnutrition in all its forms the leading contributors to the global burden of disease(6), but also food systems are not operating within some planetary boundaries and are contributing to widespread and potentially irreversible environmental breakdown degradation, including potentially irreversible disruption(7). Understanding the impact of population dietary intake has extended beyond health and the ability of food systems to provide sufficient quantity, quality and diversity of safe, affordable and nutritious foods, to interlinkages of diets and food systems with climate change, water and land pollution, deforestation and biodiversity loss and other forms of environmental degradation(7). The focus on healthy diets from sustainable food systems connects all parts of food supply chains (from food production to consumption) and the social, economic and environmental outputs of those systems(8). Unsustainable food systems producing unhealthy diets is the status quo, a lose–lose dynamic for both human health and the environment. Nevertheless, in principle there is hope. A system disruption might possibly flip new governance arrangements and policy actions for transforming food systems to win–win have been articulated. Certainly there is evidence to support the premise that ‘a healthy diet is a sustainable diet’ and vice versa(9). However, achieving these actions presents a major challenge. Food systems are multidimensional socio-ecological systems which involve many actors with diverse interests and worldviews, impacted by policies from sectors including agriculture, food, health, finance, trade and environment(10). This means that some of the win–win actions may struggle to achieve full societal and political acceptance, for example the highly contested issue of meat reduction(11). Whether a healthy diet is a sustainable diet will also depend on nuances including the circumstances under which different types of foods are produced and consumed(12). Therefore, some trade-offs between various competing priorities will need to be made whereby one consideration is prioritised over others. There is a need to embrace system-wide and integrated approaches to interventions (i.e. multiple policy and programming actions that work synergistically on different components and levels of the system)(13). After decades of relative neglect, the need for healthy and sustainable food systems is now receiving greater political attention by governments, international organisations, business groups and civil society organisations. Over the years Public Health Nutrition has taken a leadership role in drawing attention to the topic, stimulating academic debate regarding important considerations and highlighting actions that might be taken. It has done this through the publication of numerous peerreviewed papers, a special issue(14), a supplement(15) and a targeted editorial(16). The momentum for change is building as academics, civil society and commercial interests across a variety of sectors come together to address these important and difficult issues. One landmark example of this is the ‘Food in the Anthropocene: the EAT-Lancet Commission on healthy diets from sustainable food systems’ report (EAT-Lancet report)(2) launched in Stockholm in June 2016(17). Thirtyseven scientists worked together over two-and-a-half years to build the evidence base for this important report. In an increasingly polarisedworld where social media influences public understanding of issues(18), the attempt to bring together experts from various academic fields for evidence assessment is to be commended.