Objective: To develop a policy formulation tool for strategically informing food and nutrition policy activities to promote healthy and sustainable diets (HSD).Design: A policy formulation tool consisting of two complementary components was developed. First, a conceptual framework of the environment–public health nutrition relationship was constructed to characterise and conceptualise the food system problem. Second, an ‘Orders of Food Systems Change’ schema drawing on systems dynamics thinking was developed to identify, assess and propose policy options to redesign food systems.Setting: Food and nutrition policy activities to promote HSD have been politicised, fragmented and lacking a coherent conceptual and strategic focus to tackle complex food system challenges.Results: The tool’s conceptual framework component comprises three integrated dimensions: (i) a structure built around the environment and public health nutrition relationship that is mediated via the food system; (ii) internal mechanisms that operate through system dynamics; and (iii) external interactions that frame its nature and a scope within ecological parameters. The accompanying schema is structured around three orders of change distinguished by contrasting ideological perspectives on the type and extent of change needed to ‘solve’ the HSD problem.Conclusions: The conceptual framework’s systems analysis of the environment–public health nutrition relationship sets out the food system challenges for HSD. The schema helps account for political realities in policy making and is a key link to operationalise the framework’s concepts to actions aimed at redesigning food systems. In combination they provide a policy formulation tool to strategically inform policy activities to redesign food systems and promote HSD.

Dietary change has been suggested as a key strategy to maintain food security, improve health and reduce environmental impacts in the face of rising populations, resource scarcity and climate change impacts, particularly in developed countries. This paper presents findings from a quantitative modelling analysis of food availability and environmental implications of shifting the current average Australian dietary pattern to one of two alternative, healthy dietary patterns, the ‘healthy mixed diet’, with a mixture of animal and plant foods, and the ‘healthy plant-based diet’, with only plant foods. Both were constructed in accordance with the Australian Dietary Guideline recommendations, and four sustainability principles: Avoiding over-consumption, reducing intake of discretionary foods, reducing animal products, and reducing food waste. It was assumed that all food was provided domestically where possible, and export of foods only occurred when there was a surplus to domestic requirements. The authors compared the impacts of each dietary pattern on direct food availability, water use, land use, greenhouse gas emissions, fuel and energy use and fertiliser use. The plant-based diet had the best overall environmental and direct food availability outcomes, however had key vulnerabilities in terms of fertiliser and cropping land availability. For the agricultural sector overall, changes in diet had little effect on environmental impact due to the amount and nature of Australian exports, indicating that changes to production methods are also necessary. Likewise, changing diets had little effect on the existing environmentally intensive Australian economy, indicating that changes to other sectors are also necessary.

Food insecurity arises in circumstances where individuals or families cannot meet their most basic need for food. This problem is particularly common in remote mountain areas where the shortage of arable land and a harsh climate make it impossible to produce a sufficient quantity and diversity of food throughout the year. This investigation forms part of a project to improve food security using solar technology in Humla, an impoverished mountain region in Nepal. In similar locations, increased food production and preservation have been achieved using solar greenhouses and dryers. However, a systematic approach, where these technologies are used in a complementary way to supply the shortfall in food and address nutritional deficiencies has not been attempted. This paper describes the selection, construction and testing of an existing greenhouse design in Humla. An initial design selection was devised that was based on existing high altitude greenhouses but modified to incorporate locally available materials. A TRNSYS model was then created and validated from measured data. The model has then been used to explore methods to improve the performance and reduce costs of the basic design and further adapt it to the local climate