Globally, diet quality is poor, with populations failing to adhere to national dietary guidelines.⁽¹⁾ Such failure has been consistently linked with poorer health outcomes.⁽²⁾ Examples of malnutrition include both under- and over-nutrition, with overweight and obesity now a significant health problem worldwide.^{(Reference Swinburn, Kraak and Allender3)} Other commonly occurring examples of malnutrition are micronutrient deficiencies, with iron, vitamin A and iodine deficiencies being the most frequently occurring globally. These nutritional challenges have been influenced by recent global world events, including the COVID-19 pandemic, the war in Ukraine and the related economic uncertainties; with all of these events influencing food supply and food security. Diet and health status is socio-economically patterned, and such inequalities are likely to have been enhanced as a result of these recent events. In addition to the impact of diet on health outcomes, it is increasingly recognised that what we eat, and the resulting food system, has significant environmental or planetary health impacts, and research activity is growing in terms of understanding the detail of these impacts, what changes are required to reduce these impacts and also how the impact of climate change on our food supply can be mitigated. Given the complexity of the interactions between climate change, other world events, food and health, and the different actors and drivers that influence these, a systems thinking approach to capture such complexity is essential.⁽⁴⁾ Such an approach will help address the challenges set by the UN 2030 Agenda for Sustainable Development in the form of the Sustainable Development Goals, which are a call to action to end poverty and inequality, protect the planet, and ensure that all people enjoy health, justice and prosperity.⁽⁵⁾ Progress against SDGs has been challenging, with an ultimate target of 2030. While the scientific uncertainties regarding diet and public and planetary health need to be addressed, equal attention needs to be paid to the structures and systems, as there is a need for multi-level, coherent and sustained structural interventions and policies across the full food system/supply chain to effect behavior change. Such systems-level change must always keep nutritional status, including impact on micronutrient status, in mind. However, benefits to both population and environmental health could be expected from achieving dietary behaviour change towards more sustainable diets.