The United States Food Loss and Waste Reduction Goal seeks to reduce national food waste by 50%, down to 74 kg per capita, by 2030. Here we investigate state policies' alignment with the federal goal across four policy categories. We develop a policy scoring matrix and apply it to wasted food solutions listed in the non-profit ReFED's database to derive ranges of food waste diversion potential and projected generation across states. On the basis of state policies alone, no state can meet the federal target. We estimated a diversion potential of 5-14 kg per capita and a food waste generation of 149 kg per capita nationally in 2022, equivalent to the 2016 baseline. Without additional intervention at the state and federal level promoting a shift from food waste recycling towards prevention, rescue and repurposing, food generation in the United States will probably remain high.

Growing evidence suggests that diets high in ultra-processed foods (UPFs) are harming human and planetary health. UPFs therefore pose a complex regulatory challenge, yet, to date, little research has systematically assessed how governments have responded to UPFs in national food policies. Here we analyse data from the NOURISHING database to assess the scope and strength of UPF-related regulatory interventions worldwide, using three frameworks-namely, NOURISHING, the Nuffield Ladder and the Modalities of Control framework. Of the 417 UPF-related measures identified, most imply food processing or mention UPF examples rather than refer to processing or UPFs specifically. The scope of action is narrow; 85.9% of interventions change the food environment, largely represented by nutrition labelling. The strength of action is limited; interventions are skewed towards informational measures to influence consumer choice, and 47.1% of measures use consensus to shape food business conduct. These findings highlight an opportunity to broaden the scope and strength of UPF-related regulation.

Due to complex interactions, changes in any one area of food systems are likely to impact-and possibly depend on-changes in other areas. Here we present the first annual monitoring update of the indicator framework proposed by the Food Systems Countdown Initiative, with new qualitative analysis elucidating interactions across indicators. Since 2000, we find that 20 of 42 indicators with time series have been trending in a desirable direction, indicating modest positive change. Qualitative expert elicitation assessed governance and resilience indicators to be most connected to other indicators across themes, highlighting entry points for action-particularly governance action. Literature review and country case studies add context to the assessed interactions across diets, environment, livelihoods, governance and resilience indicators, helping different actors understand and navigate food systems towards desirable change.

Food systems are essential for the achievement of the United Nations Sustainable Development Goals in China. Here, using an integrated assessment modelling framework that considers country-specific pathways and covers 18 indicators, we find that most social and environmental targets for the Chinese food system under current trends are not aligned with the United Nations Agenda 2030. We further quantify the impacts of multiple measures, revealing potential trade-offs in pursuing strategies aimed at public health, environmental sustainability and livelihood improvement in isolation. Among the individual packages of measures, a shift towards healthy diets exhibits the lowest level of trade-offs, leading to improvements in nutrition, health, environment and livelihoods. In contrast, focusing efforts on climate change mitigation and ecological conservation, or promoting faster socioeconomic development alone, have trade-offs between social and environmental outcomes. These trade-offs could be minimized by bundling all three aspects of measures.

Rice is a major source of greenhouse gas (GHG) and nitrogen pollution. While best management practices have been developed to enhance the sustainability of rice production under current climates, their adaptability and efficacy under future climate scenarios remain uncertain. Here we evaluated 49 best management practices across global grid cells of rice-producing areas in terms of increasing rice production, reducing GHG emissions and minimizing nitrogen pollution under future climate conditions. Optimal climate adaptation measures were assigned to each grid cell. We show that implementing the proposed adaptation strategy could increase global rice production by 36% while reducing GHG emissions and nitrogen losses by 23% and 32%, respectively. This approach could lead to a global benefit of US$117 billion for food supply, resource saving, climate mitigation and environmental protection, with total implementation costs of US$13 billion. Establishing practical and cost-effective adaptation strategies is critical for the sustainable development of the global agricultural system in the face of climate challenges.

Fiscal policies can provide important incentives for encouraging the dietary changes needed to achieve global policy targets. Across Europe, the foods relevant to health and the environment often incur reduced but non-zero value-added tax (VAT) rates at about half the maximum rates, which allows for providing both incentives and disincentives. Integrating economic, health and environmental modelling, we show that reforming VAT rates on foods, including increasing rates on meat and dairy, and reducing VAT rates on fruits and vegetables can improve diets and result in health, environmental and economic benefits in most European countries. The health improvements were primarily driven by reductions in VAT rates on fruits and vegetables, whereas most of the environmental and revenue benefits were driven by increased rates on meat and dairy. Our findings suggest that differentiating VAT rates based on health and environmental considerations can support changes towards healthier and more sustainable diets in Europe.

Dryland grazing sustains millions of people worldwide but, when poorly managed, threatens food security. Here we combine livestock and wild herbivore dung mass data from surveys at 760 dryland sites worldwide, representing independent measurements of herbivory, to generate high-resolution maps. We show that livestock and wild herbivore grazing is globally disconnected, and identify hotspots of herbivore activity across Africa, the Eurasian grasslands, India, Australia and the United States. Wild herbivore dung mass was negatively correlated with total organic nitrogen, yet strong site-level correlations exist between our livestock dung estimates and total soil organic nitrogen. Using dung mass as a proxy of herbivore abundance enables standardized, field-based measures of grazing pressure that account for different herbivore types. This can improve herbivore density modelling and guide better management practices for populations that rely on dryland-grazing livestock for food.

Climate change poses substantial challenges to agriculture and crop production, but the combined role of nitrogen and water inputs in adaptation has been largely overlooked. Here, by developing regression models using US county-level data (2008-2020), we demonstrate that integrated optimization of irrigation and nitrogen inputs represents the most resource-efficient strategy to offset the climate-related yield losses. Under the 1.5 °C (3 °C) warming scenario, this approach involves increasing irrigation water withdrawals for maize by 62% (67%) and reducing it for soybean by 65% (58%), while increasing nitrogen inputs for maize by 4% (13%) and for soybean by 10% (130%) annually. This strategy reduces unsustainable irrigation water withdrawals by 73% (56%) for maize and 26% (28%) for soybean, enhancing water sustainability. Cost-benefit analysis indicates this optimization is cost-effective for over 80% of US maize and soybean productions, underscoring its critical role for climate change adaptation.

The offering of grocery stores is a strong driver of consumer decisions. While highly processed foods such as packaged products, processed meat and sweetened soft drinks have been increasingly associated with unhealthy diets, information on the degree of processing characterizing an item in a store is not straightforward to obtain, limiting the ability of individuals to make informed choices. GroceryDB, a database with over 50,000 food items sold by Walmart, Target and Whole Foods, shows the degree of processing of food items and potential alternatives in the surrounding food environment. The extensive data gathered on ingredient lists and nutrition facts enables a large-scale analysis of ingredient patterns and degrees of processing, categorized by store, food category and price range. Furthermore, it allows the quantification of the individual contribution of over 1,000 ingredients to ultra-processing. GroceryDB makes this information accessible, guiding consumers toward less processed food choices.

Despite the growing accessibility of international grain and oilseed markets, high production costs and trade frictions are still prevalent, contributing to regional heterogeneities in the landed cost of grain imports. Here we quantify the landed cost for six grain commodities across 3,500 administrative regions, capturing regional cost differences to produce grain and transport it across international borders. We find large heterogeneities in the costs of imported grain, which are highest in Oceania, Central America and landlocked Africa. While some regions have uniform landed costs across sourcing locations, others face cost variations across trading partners, showing large inequalities in access. We find that most regions could benefit from a targeted approach to reduce landed cost while others benefit from a mixed strategies approach. Our results highlight that spatial information on production, trade and transport is essential to inform policies aiming to build an efficient and resilient global agricultural commodity trade system.

Nutritional epidemiology aims to link dietary exposures to chronic disease, but the instruments for evaluating dietary intake are inaccurate. One way to identify unreliable data and the sources of errors is to compare estimated intakes with the total energy expenditure (TEE). In this study, we used the International Atomic Energy Agency Doubly Labeled Water Database to derive a predictive equation for TEE using 6,497 measures of TEE in individuals aged 4 to 96 years. The resultant regression equation predicts expected TEE from easily acquired variables, such as body weight, age and sex, with 95% predictive limits that can be used to screen for misreporting by participants in dietary studies. We applied the equation to two large datasets (National Diet and Nutrition Survey and National Health and Nutrition Examination Survey) and found that the level of misreporting was >50%. The macronutrient composition from dietary reports in these studies was systematically biased as the level of misreporting increased, leading to potentially spurious associations between diet components and body mass index.

Food systems require urgent transformation towards social and ecological sustainability. Degrowth posits a radical pathway of transformation to reduce ecological impacts while increasing well-being and reducing inequality. Here we highlight that degrowth and food systems-albeit both linked to transformation-are not well integrated. We conduct a conceptual exploration of the potential alignment between key food systems and degrowth transformation measures, arguing for complementary and reciprocal perspectives to theorize and enact transformation. Finally, we offer concrete practical actions to integrate degrowth and food systems, thereby widening the narrative and analytical lens of social-ecological transformation.

Tibetan barley (Hordeum vulgare) accounts for over 70% of the total food production in the Tibetan Plateau. However, continuous cropping of Tibetan barley causes soil degradation, reduces soil quality and causes yield decline. Here we explore the benefits of crop rotation with wheat and rape to improve crop yield and soil quality. We conducted 39 field experiments on the Tibetan Plateau, comparing short-term (≤5 years), 5-10 years and long-term (≥10 years) continuous cropping with rotation of Tibetan barley with wheat or rape. Results showed that Tibetan barley-wheat and Tibetan barley-rape rotations increased yields by 17% and 12%, respectively, while improving the soil quality index by 11% and 21%, compared with long-term continuous cropping. Both Tibetan barley rotations with wheat and rape improved soil quality and consequently yield, mainly by increasing soil microbial biomass nitrogen and microbial biomass carbon and decreasing pH. By contrast, long-term continuous cropping led to decreased soil organic matter, lower microbial biomass nitrogen and increased pH, contributing to yield decline. The benefits of rotations on crop yield and soil quality increased over time. Implementing crop rotation with wheat or rape thus offers a sustainable agricultural strategy for improving food security on the Tibetan Plateau.