Every year roughly 2.9 trillion pounds of food—about a third of all the food available—never gets eaten. A huge part of this is from crops left in the fields or food discarded during processing worldwide. In the United States and other countries with more advanced food delivery systems, consumers are responsible for a bigger share of lost and wasted food than in developing countries.

This mountain of food doesn’t get dumped all at once. It adds up forkful by forkful from overflowing plates, in forgotten carry-out containers at the back of cluttered refrigerators, and on counters and in cabinets when schedules get in the way of ambitious cooking plans.

The flip side, of course, is that that waste can be cut down by