According to a recently released report on the world's water situation, the world's population should move toward an almost completely vegetarian diet over the next forty years, in order to prevent catastrophic food shortages. The report, by researchers at the Stockholm International Water Institute, estimates that humans currently derive about 20% of their protein from animal-based foods, but that this will need to drop to about 5%, if we hope to feed the growing world population. A meat-based diet requires 5-10 times the amount of water than a vegetarian diet, and this level of water consumption is simply unsustainable. Water scarcity is already limiting food production, according to Oxfam, and pressure is only going to increase as the population grows and water availability shrinks. Drought in the U.S. and Russia, and weak monsoons in Asia, have already caused prices for staple food items such as corn and wheat to rise almost 50%.
The report tells us: "Nine hundred million people already go hungry and 2 billion people are malnourished...with 70% of all available water being in agriculture, growing more food to feed an additional 2 billion people by 2050 will place greater pressure on available water and land."