Food packages often list a “sell by,” “best by,” “enjoy by,” or “expiration” date. But if you don’t “enjoy by” that date, does it mean you’ll get “sick after”?


Dates on food labels are the manufacturers’ best guess about how long a food will taste freshest. After that date, the quality gradually declines.

“Most foods would become quite unpalatable before they would be unsafe to eat,” says Roni Neff, director of the food system sustainability & public health program at the Johns Hopkins Center for a Livable Future.

It’s not time that makes most foods unsafe

It’s that they become contaminated with bacteria from raw meat or poultry and aren’t kept cold enough or cooked thoroughly.

Part of the confusion is that many people think that the government regulates expiration dates. (Other than for infant formula, it doesn’t.)

That can also lead to waste.

“People who believe that date labels are federally regulated are more likely to throw out food on a precautionary basis,” says Neff. Ditto for those who think that “outdated” foods are unsafe.

In 2017, the food industry urged companies to use only one of two terms on packages: “BEST if used by” and “USE by.”

(Congress is considering the Food Date Labeling Act, which would require one of those two terms on foods that carry expiration dates. Many companies are already using them.)

“The ‘BEST if used by’ label is meant to be about quality,” explains Neff. “The ‘USE by’ label is meant to be about whether the food is safe.”

Which foods would get which label?

“Most foods will not need a label at all, or they would get the ‘BEST if used by’ label,” says Neff.

“The few foods that become unsafe because of time would get a ‘USE by’ label. It’s mainly for foods where Listeria is a concern, because it can grow under normal storage conditions.”

(Listeria typically grows on deli meats, smoked fish, and prepared foods. It’s responsible for listeriosis, the hard-to-diagnose infection that can cause miscarriage in pregnant women and symptoms like fever, diarrhea, headache, and stiff neck.)

The bottom line

Most date labels tell you about a food's quality, not safety. But be more wary of pathogens if a food is past its “USE by” date.

Photo: andy0man/

a bowl of oatmeal granola with peanuts blueberry and banana


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