Couple Bought 21-Year-Old Box of Cereal off Shelves at Walmart

An Illinois Walmart store photographed in January. A Colorado couple claims they purchased a 21-year-old box of cereal from the chain store. Scott Olson/Getty Images

Most people agree there's some leeway with expiration dates—but eating a day-old slice of cheese is different from a bowl of 21-year-old cereal. A family in Lakewood, Colorado, claims they purchased a box of Quaker 100% Natural Granola cereal from a Walmart store in Littleton, Colorado, with a best-by date from more than two decades ago, reported ABC affiliate Denver7.

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"It looks like February 22, 1997," Anthea Carelse told the station of the "best by" date printed on the box.

According to the station, Anthea only had a small serving, but her husband, Josiah, ate much more.

"I had about two bites, and that was it," she said. "I was like, 'Josiah, you're going to be really sick.'" The variety purchased included oats, honey and raisins.

The station did verify that the UPC on the cereal box matched the one found on the Walmart receipt. The store is investigating but has not provided a reason why the cereal might still be on shelves.

This particular box was printed with a "best by" date, which gives the time when the product will taste the best, according to the United States Department of Agriculture. "Sell by" is how long stores can display the product, while "use by" indicates the last possible date you'll get the best quality. None of these indicate safety dates.

The U.S. Food and Drug Administration advises consumers that foods can be eaten a few days after their printed dates, though time frames aren't specified.

Food scientist Dana Gunders, of the Natural Resources Defense Council, explained that food will typically become less appetizing before actually causing harm. "Foodborne illness comes from contamination, not from the natural process of decay," Gunders told Consumer Reports in 2015. "And our senses are well-equipped to recognize decay."

You'll know when a food has spoiled through taste, scent or texture. And though you might not want to eat 21-year-old cereal, it's worth mentioning Josiah made it through the entire bowl.

"I just started eating and thinking: 'It just tastes funny. It must be OK,'" he told Denver7.