Diversified global vegetable oil production can mitigate climate change and increase other environmental and socioeconomic benefits.

Global vegetable oil production is a crucial ingredient for food and household products but also a major source of greenhouse gas (GHG) emissions and other environmental externalities. A diversified supply may improve the sustainability and resilience of profitable vegetable oil production globally. Here, we provide the first spatial assessment of the environmental and economic effects of the globally dominant vegetable oil crops soybean, oil palm, rapeseed, sunflower, groundnut, and olive globally, based on new data from a meta-analysis, life cycle assessment, and process-based crop growth modelling. We show that the total annual GHG emissions, water use, land use, pesticide use, and farmer income of the six vegetable oil crops are 1.2 Gt CO2eq/year, 876.0 km3/year, 168.3 Mha/year, 953.6 kt/year, and 66.5 billion USD/year, respectively. We also found that diversified vegetable oil production, for instance, through increased fractions of a highly productive oil tree crop Camellia oleifera can reduce GHG emissions, water use, land use, and pesticide use by 14.0%, 4.9%, 7.3%, 9.3%, respectively and increase farmer income by 82.6%. When considering enabling conditions for technology and policy support in a technology-policy-enabling scenario, these benefits increase 1.3, 2.1, 1.8, 1.7, and 3.2 folds, respectively. Our results provide practical guidance on where and how diversified oil crop production can advance a sustainable food system transformation and help to mitigate climate change.