How do dietary choices affect the environment? The nitrogen footprint of the European Union and other dietary options

There is a growing interest in diets with respect to health and fitness. However, food production and consumption have been identified as major sources of environmental impacts. In this study, the maximum nitrogen (N) footprint of the European Union has been used as an indicator to describe the reactive nitrogen losses using food consumption and production data. The maximum N footprint for the European Union food supply was 23.8 kg N/capita/year and the main food categories contributing to this footprint were dairy, pork, and cereals. Additionally, the N footprint was calculated for five dietary patterns: vegan, lacto-ovo vegetarian, pesco-vegetarian, semi-vegetarian and non-vegetarian. Dietary preferences towards a vegan and a lacto-ovo vegetarian diet showed a reduction in the total N footprint of 25% and 24%, respectively, with respect to the non-vegetarian diet. The pesco-vegetarian and semi-vegetarian diet presented also a reduction in the amount of N released, 17% and 15%, respectively. Although the semi-vegetarian diet includes the consumption of meat and meat production is less N-efficient than fish production, a tradeoff is observed by the increase in fish consumption resulting in similar N footprints. Assessing different dietary patterns and analyzing possible changes in food consumption can lead to significant improvements in the N footprint. This study can serve as the starting point to consider food consumption as a way of influencing to some extent the environmental impacts produced by N release.