Moving away from animal-based protein consumption requires major changes in how food systems operate. This Perspective explores three paradoxes driving the transition and alternative, interconnected approaches to support protein system sustainability.

Fisheries and aquaculture production are key to livelihoods, food and nutrition, yet over one-third of global aquatic harvest is lost or wasted. The post-harvest sector, key to reducing these losses, and dominated by women workers, is not well understood. This systematic review synthesizes evidence on equity and equality outcomes of post-harvest practices and technologies that aim to reduce loss and waste in the fisheries sector.

Carbon sequestration on agricultural land holds great promise for combating climate change. This study estimates the mitigation potential of three sequestration practices—soil carbon enhancement, biochar application on cropland and silvo-pastoral systems—while identifying cost-effective mitigation portfolios.

The use of biomarkers to complement traditional dietary assessment methods can help strengthen findings from nutritional epidemiologic studies. This study identifies plasma proteomic signatures that reflect the response to healthy dietary patterns and are associated with reduced incidence of chronic disease and mortality.

Staple crop production in China involves high levels of synthetic fertilizer use and losses to the environment. Using a localized nitrogen management model for wheat, maize and rice, this study estimates the environmental and economic benefits of improving nitrogen use efficiency at the county level.

Mercury exposure from fish consumption poses a risk to human health, and effective mercury management is hampered by uncertainty about how human activities affect mercury levels in fish. This study presents global geographic variations in total mercury and methylmercury levels in fish and quantifies the impact of human activities.

Carbon sequestration on agricultural land holds great promise for combating climate change. This study estimates the mitigation potential of three sequestration practices—soil carbon enhancement, biochar application on cropland and silvo-pastoral systems—while identifying cost-effective mitigation portfolios.

A dataset including 29 countries and life-cycle assessment highlights the environmental impact of school plate food waste. A sustainable food education framework is presented to support early intervention and wasteful behavioural changes.

Maize yield variability in sub-Saharan Africa has important implications for food security and livelihoods. By combining the time specificity of weather-related impacts on crops and different agroclimatic zones, this study shows that shifts in sub-seasonal dry–wet spell patterns are a major contributor to this variability.

The framework presented in the Dublin Declaration has generated controversy by advocating for maintaining or increasing livestock numbers. The serious and acute harms associated with global livestock production today bring the goals of the declaration into dispute.

Malnutrition and climate change are intimately linked. Nature Food’s latest Collection illustrates the central role of diets in both of these issues, underscoring the burden of current diets on human and planetary health, as well as how much improvement can be achieved through better dietary choices.

Not only does the problem persist, but it is also getting worse. Nature Food’s Collection ‘Loss and waste in food systems’ is a contribution to the debate on drivers, impacts and solutions.

A focus on improvements to livestock production limits the scope for food systems transformation. Research, policy and industry must adopt measures to downsize livestock production and consumption to meet sustainability targets and facilitate a just transition.