We’ve all done it.

Ignore the date on the jug of milk so long is it passes the sniff test.

If the smell doesn’t knock us out of our shoes, it’s safe, right?

“The sniff test is very effective,” Dana Gunders, senior scientist at the Natural Resources Defense Council (NRDC), told Healthline. “A lot of things can’t grow on dairy.”

universal expiration date

The simple reason that milk and other foods are still plenty good enough to consume after the date printed on their package is the language used to describe it.

“Best by,” “sell by,” and other such warnings don’t mean the contained food will be putrid on the day after expiration. In many cases, except for things like deli meats, the food has plenty of shelf life ahead of it.

“What phrase is used is up to the manufacturer,” Gunders said. “Consumers are not distinguishing between these dates.”

Experts say this confusion directly contributes to unnecessary food waste.

Some estimates say of all food in the United States ends up in the trash, and 40 percent of that is due to consumers.

That adds up to about $162 billion in waste each year, calculating in the water, land, labor, and other factors needed to create that food.

The average family of four spends roughly $1,500 a year on food they’ll never eat.

A survey of 1,000 people conducted by Harvard Food Law and Policy Clinic, the National Consumers League, and the Johns Hopkins Center for a Livable Future found about a third of consumers believe expiration dates and terms are federally regulated.

They’re not, at least now.

“Some people believe there’s a very official system behind these dates. There isn’t,” Gunders, who also wrote the “Waste-Free Kitchen Handbook.”

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A Common Language

While the U.S. Food and Drug Administration (FDA) is revamping what’s on a food nutritional label, state and federal legislators are hoping to use common language on food expiration dates.

California lawmakers — who love to get ahead of federal legislation — introduced a bill that would have given food packaging “expires on” dates and an “elevated risk date.”

It has received support from environmental, academic, municipal, and waste management groups. The major opposition comes from agricultural and grocer’s associations.

Meanwhile at the federal level this week, Sen. Richard Blumenthal, D-Conn., and Rep. Chellie Pingree, D-Maine, also introduced legislation to standardize dates on food to reduce waste and keep people from throwing out food that’s safe to eat.

“Items at the grocery store are stamped with a jumble of arbitrary food date labels that are not based on safety or science,” Blumenthal said in a joint press release. “This dizzying patchwork confuses consumers, results in food waste, and prevents good food from being donated to those who need it most.”

“It's time to settle that argument, end the confusion, and stop throwing away perfectly good food,” Pingree said.

The bill was introduced to the Senate on Wednesday, but GovTrack.us, a nongovernment website that tracks legislation, gives the bills a 2 percent chance of ever becoming law.

Read More: Should ‘Exercise Equivalents’ Be Part of Food Labeling? »

To Eat or Not to Eat

Buying food just to throw it away sounds like a silly thing, but that’s what Americans do.

The NRDC and the AdCouncil have teamed up with public campaigns to help people realize the errors in their ways.

The “Save the Food” campaign highlights the fact that food is the largest component of solid trash in landfills and 25 percent of freshwater is used to grow food that will get scrapped.

The campaign has even attracted the attention of Tom Colicchio, celebrity chef and founder of Food Policy Action.

“It’s not just good food getting thrown away that upsets me as a chef,” he said in a press release. “It’s that everything that goes into producing that food — the land, the water, the climate pollution, the labor, and the love it takes to get it to the plate — all of it also gets wasted. We have a great opportunity to fix this problem. Stopping food waste starts at home.”

But correct labeling on when a food truly goes bad is a good start, Gunders said.

“Generally, people don’t get sick from aging food,” she said. “They get sick from contaminated food, whether it’s old or not.”

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