According to a report issued by the Stockholm International Water Institute last week, as much as half of all the food produced globally is either wasted or lost as it makes its way through the food chain—a stunning figure given the 850 million people in the world who are malnourished. The causes vary: In developing nations, most of the waste occurs because of poor harvesting techniques or insufficient storage facilities that leave crops susceptible to infestations or rot. (In Kenya and Uganda alone, for instance, a combined $45 million worth of milk is lost to spoilage each year.)

In rich countries, by contrast, most food waste amassed is a result of the carelessness that comes with food being so cheap.  Retailers, cafeterias and restaurants toss out an average of 122 lbs a month per family of four. In American households alone, an estimated $843 billion worth of food is thrown out each year—that's not counting banquet halls, hospitals, etc.

Then there's water—agriculture uses nearly 70 percent of all freshwater withdrawn for human use annually and a great deal of that is unavailable for reuse, straining resources in areas already struggling to survive with limited water supply. Meat production is especially water intensive, as illustrated by California's beef recall earlier this year: The 65 million kilograms of ruined meat required some 650 billion liters of water, mostly to grow crops for animal feed, which would've been enough to supply the entire city of Las Vegas for a year. As poorer countries like China get rich and start eating meat, meat demand is expected to rise anywhere from 70 to 160 percent by 2050, boding ill for the world's already-strained water supplies.

The SIWI report offers up a number of suggestions to cut down on agricultural waste—from improving rainfall capture to employing more efficient harvesting and storage techniques in developing countries. A lot of it will involve better federal coordination of land and water management agencies—something a number of countries, the U.S. included, are sorely lacking.

--Marin Cogan