Both human health and the environment are directly influenced by dietary patterns. The EAT-Lancet commission on Food, Planet, Health has proposed an optimal diet if humanity wants to sustainably feed itself in 2050. Their analysis assumes global trade remains as business as usual. However, locally sourcing food has often been claimed to be less environmentally taxing. This analysis aimed to answer to what extent countries can be self-sufficient in growing the EAT-Lancet diet, and what the impact on land use and reactive nitrogen input to soils would be. Results here show that although a surprisingly large number of countries would be likely to be self-sufficient and some large countries could see environmental benefits, the global reactive nitrogen input and land use would be pushed far outside of planetary boundaries if global food trade were to disappear. This is mainly due to increased livestock consumption and production inefficiencies in Africa and Asia. Ultimately, although the environmental benefits of local production are real in some regions, global trade contributes to an efficient and sustainable global food system.