A recent study conducted by the Natural Resources Defense Council, and Harvard Food Law and Policy Clinic has found that 90 percent of Americans mistake the "use by" dates on food products for expiration dates. In fact, the date is merely a suggestion by the manufacturer, informing customers of the product's optimal freshness.
This misleading scenario of expiration dates versus "use by" dates, according to researchers, has cost American consumers billions of dollars due to premature discarding of food.
“Expiration dates are in need of some serious myth-busting because they’re leading us to waste money and throw out perfectly good food, along with all of the resources that went into growing it,” says Dana Gunders, an NRDC staff scientist. “Phrases like ‘sell by,’ ’use by,’ and ‘best before’ are poorly regulated, misinterpreted and leading to a false confidence in food safety.”
Read more about this study at Yahoo! News.