The Water Footprint of Diets

Source: Advances in Nutrition
Year: 2020
Type: Systematic Review and Meta-Analysis

This systematic review and meta-analysis published in Advances in Nutrition examines how different dietary patterns influence water use across global food systems. By synthesizing data from 41 studies covering 176 countries, the research provides one of the most comprehensive assessments of the relationship between diet and water footprint.

The study finds that dietary patterns emphasizing plant-based foods are generally associated with lower overall water use compared to diets high in animal products. This difference is largely driven by the significant water inputs required for livestock production, including feed cultivation, drinking water, and processing.

The research distinguishes between different types of water use, including total water use and blue water use (surface and groundwater). While healthier diets tend to reduce total agricultural water use, the effects on blue water use are more variable depending on the specific foods consumed and where they are produced.

A key strength of this study is its global scope and meta-analytic design, which allows for the identification of consistent patterns across diverse populations and agricultural systems. By combining results from multiple studies, the research provides stronger and more reliable conclusions than individual studies alone.

The findings highlight the importance of considering both dietary composition and production methods when evaluating environmental impact. While not all plant-based foods have the same water footprint, overall dietary patterns that prioritize whole plant foods tend to be more water-efficient.

For The Ark of Compassion, this study reinforces a clear insight: dietary choices play a significant role in shaping global water use, and plant-forward eating patterns can contribute to more sustainable freshwater management.