The following information (italics) comes from the recently published, “Diet Change – A Solution to Reduce Water Use?” an open access article.
Go Vegan, Save Water
We found that reducing animal product consumption would impact global green water use by reducing it up to 21%, while the effect on blue water use in food production would be slightly smaller, 14% at most. Our study considerably extends the current understanding of diet change impacts on water consumption on a global scale, as previous studies have been done at either the regional or national level (Vanham et al 2013, Renault and Wallender 2000, Ercin and Hoekstra 2014, Springer and Duchin 2014) or for only specific foodstuffs or diets (Baroni et al 2006, Marlow et al 2009, Reijnders and Soret 2003). Further, our findings provide complementary information on existing global estimates of diet change impacts on the global food supply (Foley et al 2011) and comparable information on, for example, food loss reduction on the global food supply (Kummu et al 2012).
FYI: The study defines “blue water” as freshwater in rivers and aquifers and “green water” as naturally infiltrated rain, attached to soil particles and accessible by roots.
Go Vegan, Feed 1.8 Billion People
Our results can also be compared with other suggested actions to increase food availability or to reduce the environmental burden of food production. By adjusting diets to the recommended energy intake and composition, total water footprints would be reduced from 2738 l/cap/day to 2682 l/cap/day, while a diet without meat, milk and eggs would reduce the global mean water footprint further to 2149 l/cap/day. The use of current volumes of water with a lower dietary water footprint would allow the production of more food to feed an additional 136 million people (RD scenario) or even 1.8 billion people (A0 scenario). This would, however, require that similar improvements of efficiencies are possible for other resources used in food production, as well the avoidance of improvements in water use and in the increased food supply, which would cause an additional environmental burden with regard to other resources (e.g., crop nutrients, land).
Diet change — a solution to reduce water use? M Jalava, M Kummu, M Porkka, S Siebert and O Varis M Jalava et al 2014 Environ. Res. Lett. 9 074016
doi:10.1088/1748-9326/9/7/074016 © 2014 IOP Publishing Ltd
Received 15 April 2014, accepted for publication 8 July 2014
Published 31 July 2014