As demand for animal-based food increases especially as population grows, the strain on this finite resource will intensify. A report by the University of Twente in the Netherlands which focuses on water engineering and management calculated the volume of water expended to produce a given amount of food in tons and to generate nutritional energy measured in calories. As the charts below illustrate, beef requires a much higher expenditure of water to produce than all other food items with vegetables requiring a proportionately much smaller amount. As a protein source, pulses (lentils) also used less water per calorie delivered than meat sources (Chart 2).
The steady flow of water from lakes, rivers, groundwater, and reservoirs into farmlands is a crucial component for food production, especially in arid states which have large agricultural enterprises. Keeping our crops growing in the future may depend on ability to adapt to consuming less water intensive foods so that we always have an abundant freshwater supply.