Feeding the U.S. population requires an enormous amount of land and resources. Yet, 40 percent of food in the U.S. goes to waste. When the resources to grow that food are considered, this amounts to approximately 25 percent of all freshwater, 4 percent of the oil we consume, and more than $165 billion dollars all dedicated to producing food that never gets eaten.

http://www.nrdc.org/living/eatingwell/saving-leftovers-saves-money-resources.asp