Green, blue, and gray water contribution to the water footprint of food products
Year: 2026
Type: article
Abstract: Food production has a significant impact on water resources in terms of both water availability and quality. Different approaches and indicators are used to report the impact of food systems on freshwater resources. Among these, the water footprint (WF) has gained increasing relevance in sustainability assessments and decision-making processes. A comprehensive analysis of the relevance and significance of the three components of WF—green, blue, and gray water footprints in food commodities—is necessary for more informed decision-making when WF is proposed to evaluate the sustainability of dietary systems and food systems. With this objective, we created a database of the three WF components by conducting an extensive analysis of the published literature up to 2023, which resulted in 790 green WF data points, 793 blue WF data points, and 652 gray WF data points, which were synthesized for 193 food items, 36 food subgroups, and 14 food groups. The data analysis showed that all three components were significantly higher in animal products than in plant-based foods. The latter showed a significant difference between tree crops and herbaceous crops, which needs careful interpretation for meaningful data use, in particular for the green water component of nuts and vegetable oils. Data coverage is still very fragmented, with high data density for a few food commodities and sparse information for the majority of food items. High uncertainty is also associated with the estimation of gray WF, and standardizing methodologies and protocols might improve consistency among studies and databases.
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,353
OpenAlex ID: W7224326194