An ISU expert says Americans are caught up in an epidemic of food waste. Food science and human nutrition professor Ruth Litchfield says 40 percent of the food produced in the U.S. every year is thrown out. Llitchfield says the best way to prevent food waste is to plan ahead by making a menu before going to the grocery store and sticking to it. Llitchfield also says 160 billion pounds of edible food is thrown away because of confusion about "sell by" and "use by" dates on food packaging. She says the dates are related to quality and have nothing to do with safety.