Evaluating the Water Footprint of the Mediterranean and American Diets

Abstract

Global food demand is increasing rapidly as a result of multiple drivers including population growth, dietary shifts and economic development. Meeting the rising global food demand will require expanding agricultural production and promoting healthier and more sustainable diets. The goal of this paper is to assess and compare the water footprint (WF) of two recommended diets (Mediterranean and American), and evaluate the water savings of possible dietary shifts in two countries: Spain and the United States (US). Our results show that the American diet has a 29% higher WF in comparison with the Mediterranean, regardless of products' origin. In the US, a shift to a Mediterranean diet would decrease the WF by 1629 L/person/day. Meanwhile, a shift towards an American diet in Spain will increase the WF by 1504 L/person/day. The largest share of the WF of both diets is always linked to green water (62%-75%). Grey water in the US is 67% higher in comparison with Spain. Only five products account for 36%-46% of the total WF of the two dietary options in both countries, being meat, oil and dairy products the food items with the largest WFs. Our study demonstrates that adopting diets based on a greater consumption of vegetables, fruits and fish, like the Mediterranean one, leads to major water savings.

The water use of Indian diets and socio-demographic factors related to dietary blue water footprint

“…The differences in dietary WF can be attributed to consumption patterns (e.g. greater meat consumption in typical South European diets) and variation in the WFs of food items due to climate and yield at the location of production (Blas et al, 2016). Importantly, the high dietary blue WF demonstrates the dependency of Indian diets on ground- and surface-water resources.…”

Advancing Water Footprint Assessment Research: Challenges in Monitoring Progress towards Sustainable Development Goal 6

“…The studies by Gobin et al [14] and Evangelou et al [15] focus on showing the variability in WFs of crop production, while Kersebaum et al [16] quantify uncertainties in WF estimations. Some of the papers focus on understanding the driving forces behind increasing WFs [19][20][21][22][23]. While a few papers primarily look at water-use efficiency of production as a way to mitigate water scarcity, a few other papers analyze the role of consumption patterns.…”

“…Thirteen of the fourteen papers in this special issue consider green and blue WFs [14][15][16][17][18][19][20][21][22][23][24][25][26], while eight papers include grey WF estimation. All papers that include the grey WF specifically focus on pollution through nitrogen [14,15,17,19,21,22,25,27].…”

“…All papers that include the grey WF specifically focus on pollution through nitrogen [14,15,17,19,21,22,25,27]. The only paper that exclusively focuses on the grey WF is the one by Brueck and Lammel [27].…”

“…The study shows that the most critical driver of change that affects the future WF of production and consumption for Europe is the consumption pattern. In a case study comparing Mediterranean and American diets, Blas et al [22] focus on the effect of the consumption factor, more in particular the composition of people's diet. The paper by Marrin [23] focusses on the factor A in the IPAT equation as well, in a study on the effectiveness of changing food habits to conserve water resources in the water-scarce state of California.…”