Results

By The SWITCH Team

The SWITCH database is a science-based resource designed to bring clarity to the complex relationship between food, health and the environment. Built from carefully selected and harmonised scientific literature, it compiles, analyses and summarises robust data to provide detailed yet accessible insights into the environmental and nutritional profiles of foods commonly consumed across Europe. Featuring 401 items chosen for their relevance to European diets, the database forms the backbone of the Food Index in this app.

On the sustainability side, the database reports three key indicators: carbon footprint, water footprint and a dedicated Blue Sustainability Index that captures the ecological impacts of fisheries and aquaculture. These metrics are combined into an integrated Environmental Score, offering users a clear and practical way to compare foods. Nutritional information is equally comprehensive, covering energy, protein, total and different types of fats, carbohydrates, added sugars and fibre. Fish species are also classified as lean or fatty, and each item includes guidance on recommended consumption frequency according to the SWITCH diet.

To make this wealth of information easy to interpret, every food item is accompanied by a short, reader-friendly summary that brings together its environmental and nutritional characteristics. Developed collaboratively by the University of Campania, the University of Naples and ZALF, the SWITCH database transforms complex science into a practical tool for consumers and food providers alike.

How we made it

We began by focusing on three of the most widely used indicators in scientific literature: carbon footprint (CF), water footprint (WF), and land footprint (LF). We gathered data from open-source scientific databases, carefully verifying and cross-checking sources to avoid double counting, and merged eligible datasets. After assessing data quality, we decided to exclude land footprint due to limitations in consistency and robustness. At the same time, we carried out a dedicated analysis of blue foods, developing a Blue Sustainability Index (BSI) to capture the ecological impacts of fisheries and aquaculture for fish and shellfish sold on the EU market. We statistically analysed carbon and water footprint data, addressed uncertainty, and calculated median values across food items and groups. The aligned CF, WF, and BSI values were combined into a harmonised database, with highly uncertain data removed and gaps carefully filled. Each food item was then assigned sustainability “bands” for every indicator, which were integrated into a single Environmental Score. Finally, we linked these environmental metrics with nutritional indicators, creating the comprehensive SWITCH database — complete with a harmonised coding system to ensure consistent and reliable data extraction.

This article has been adapted from content written by Simona Castaldi, Micol Mastrocicco, Luigi Alessandrino, Cristina Masini, Margherita Martinelli, Maria Palmieri, Emilia Longobardi (all authors UNICAMP); Marilena Vitale (UNINA); Jose Luis Vincente Vincente (ZALF).