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The threat of climate change and population growth has led to calls for the adoption of environmentally sustainable diets; however, concerns have been raised over the nutritional quality of low Greenhouse Gas Emission (GHGE) diets. This study examined the relationship between measures of environmental sustainability and nutrient content of sandwiches and beverages sold in a UK university cafe. GHGE and Water Footprint Impact Indicator (WFII) values for the ingredients of sandwiches and beverages were used with recipe information to calculate GHGE (gCO2e per portion) and WFIIs (scarcity weighted litres per portion). These estimates were then combined via orthogonal regression to produce a single Environmental Impact Score (EIS); higher scores equate to greater environmental impact. The relationship between EIS and nutrient content was explored using correlation analysis. Sandwiches that contained meat and animal products as well as beverages that contained milk, cocoa, and/or coffee had the highest EIS. EIS was positively associated with the portion size of sandwiches but not the serving size of beverages. EIS was positively correlated with calories, saturated fat, and sodium. However, EIS was also positively correlated with micronutrients: iron, calcium (beverages only), and B12 (beverages only). The choice of smaller or plant-based sandwiches as well as beverages without milk would reduce environmental impact as well as caloric and sodium intake. However, the selection of low impact options may also reduce the intake of nutrients required for good health. This study revealed possible tensions between nutritional quality and environmental sustainability.