"if the average global intake of vegetables is 2,300 calories per day, how many liters of water are needed to produce these vegetable calories"

2,300 liters of water will be needed to produce the vegetables. Research had shown that underground water has more water drawn from them for human use than the water that flow into them naturally. It was reported that 2.300 liters of water is needed to produce 2,300 calories of vegetable food; 1,569,500 liters of water are needed for yearly food production.