Reduction potential of German environmental food impacts due to a planetary health diet

The current food production and consumption patterns are highly relevant for the exceedance of the planetary boundaries. Also in Germany food consumption is responsible for high environmental impacts as several studies already showed. However, not all relevant impact categories have yet been quantified for German food consumption, and also the reduction potential due to changes in dietary patterns is not fully assessed. Therefore, the aim of this paper is to analyse the environmental impacts of German food consumption with respect to impacts on climate change, biodiversity and water, and to build three scenarios for a German planetary health diet in order to identify reduction potentials.

The analysis has been conducted using life cycle assessment (LCA) according to ISO 14040 series. The modelling is based on the average German food basket at consumption level and the functional unit chosen is the food consumption for 1 year for all German citizens—the German food basket. The environmental impacts assessed within this study are greenhouse gas emissions, water consumption and water scarcity, as well as land use and related impacts on terrestrial biodiversity. Furthermore, based on the current diet (‘status quo’), three scenarios for Germany were created following the recommendations for a planetary health diet for a flexitarian, a vegetarian and a vegan diet. The scenarios were kept as close as possible to the current diet in Germany, framed by a set of rules.

The results show, that today, each person in Germany consumes on average about 2650 kcal per person and day and thus 6% more than recommended in food-based dietary guidelines developed in the planetary health diet and about 25% more than recommended in the German guidelines. This finding correlates with the fact that over 50% of German inhabitants are overweight and almost a fifth (18.5%) is obese. Regarding the global environmental impacts caused by German food consumption, 216,000 kt CO₂e are emitted (of which 46,000 kt CO₂e result from dLUC), 166,000 km² of land is occupied each year, resulting in a biodiversity impact of 12,300 BVI*km²*a and 2.401 km³ of irrigation water is consumed, which causes a water scarcity footprint of 118.6 km³_worldeq. The results confirm findings of previous studies regarding climate impacts, direct land use change and occupation, and add new findings regarding water scarcity and biodiversity impacts. Furthermore, results show reduction potentials due to changes in dietary patterns. It is interesting to note that all assessed environmental impacts, including biodiversity impacts, are highly dependent on the share of animal foods in the diet, with the exception of water consumption and water footprint. It is mainly caused by plant-based foods and strongly influenced by the origin of the plant-based products, but also by the water demand of the crop itself.