NEW YORK — The “dizzying array” of food expiration date labeling approaches of consumer packaged foods companies should be “standardized and clarified,” according to a new report issued jointly by the Natural Resources Council and the Harvard Law School Food Law and Policy Clinic.

The groups suggested that the expiration date labeling is a significant and often unnecessary contributor to the waste of up to 40% of the food supply each year, equating to $165 billion.

A study by the N.R.D.C. and Harvard, “The dating game: How confusing food date labels lead to food waste in America,” concluded that more than 90% of Americans “may be prematurely tossing food because they misinterpret food labels as indicators of food safety.”

“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,” said Dana Gunders, N.R.D.C. staff scientist with the organization’s food and agriculture program. “Phrases like ‘sell by,’ ‘use by,’ and ‘best before’ are poorly regulated, misinterpreted and leading to a false confidence in food safety. It is time for a well-intended but wildly ineffective food date labeling system to get a makeover.”

A key area of confusion is between labels aimed at businesses (“best by” dates, tools for stock control) and those for consumers (“use by” dates). Even how the latter category of labels is put together should be addressed, the groups said.

“Consumers have no way of knowing how these ‘sell by’ and ‘use by’ dates have been defined or calculated since state laws vary dramatically, and companies set their own methods for determining dates, none of which helps to improve public health and safety,” they said.

The study offers a legal analysis of “the tangle of loose federal and state laws related to date labels across all 50%.” Additionally, a number of recommendations are made, including calls to:

  • Make “sell by” dates invisible to consumers since they are business-to-business labeling information and are mistakenly interpreted as food safety dates;
  • Establish a more uniform, easily understood date label system that:
    •  utilizes consistent and unambiguous language
    • creates a clear distinction between “best by” and “safe until” dates
    • “predictably” locates the date on packaging
    • “employs more transparent methods” for selecting dates and make other changes to improve coherency;
  • Offer more safe handling instructions and “smart labels” that tap into technology to help consumers learn more about a product’s safety.

“We need a standardized, common sense date labeling system that actually provides useful information to consumers, rather than the unreliable, inconsistent and piecemeal system we have today,” said Emily Broad Leib, an  author of the report and director of the Harvard program.

According to the groups, expiration date use for food gradually emerged over the course of the 20th century.

“By 1975, a nationwide survey of shoppers showed 95% of respondents considered date labels to be the most useful consumer service for addressing freshness,” the groups said. “The widespread concern prompted over 10 congressional bills introduced between 1973-1975 alone, to establish requirements for food dating. During that time, the General Accounting Office issued a report to Congress advocating a uniform national date labeling system to avoid confusion. Despite G.A.O.’s prophetic advice, none of the legislative efforts gained enough momentum to become law. Instead, the 1970s began the piecemeal creation of today’s fractured American date labeling regime.”

The Food and Drug Administration and the U.S. Department of Agriculture are at fault for failing to “adequately exercise their authority,” instead leaving expiration labeling practices at the discretion of manufacturers, the groups said.