Can we trust the expiration dates on our food? 

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Listener Ben Umans from Chicago asks: 

A lot of perishable food items have short expiration dates, and these make sense. But if you look around your kitchen, you’ll find lots of things that say they should be used by some date really far in the future, maybe years (think peanut butter or jam or ketchup). How do they come up with these expiration dates? Can we trust them?

If you open up your pantry and find a two-year-old can of soup that just “expired,” you might be tempted to toss it out. But the dates on shelf-stable items are actually guidelines, not rules. 

Food labels are confusing, but it is okay to eat a can of soup or eat from a jar of peanut butter once you hit its “expiration” date, and sometimes even weeks or months later, depending on how you stored it. Just make sure to taste and smell your food. When a shelf-stable item bears the phrase “best if used by/before” or “use-by,” manufacturers are telling you when a product will be at its best flavor or quality, not when it’s safe to eat the product, according to the U.S. Department of Agriculture’s website. 

Some manufacturers decide their “best if used by” dates on a case-by-case basis, after subjecting products to rigorous testing and asking consumers to taste test at different stages, said Brian Roe, a farm management professor at Ohio State University. Food companies may hire a third-party to perform this testing for them. Bureau Veritas, for example, offers sensory tests to gauge a food’s odor and appearance, along with microbiological tests for foodborne pathogens.  

Nonperishable items like canned food last so long because they’re placed in airtight, vacuum-sealed containers and heat processed at 250 degrees Fahrenheit, according to the USDA. “This destroys microorganisms and inactivates enzymes,” the USDA explained. 

Because of expiration-date concerns, consumers end up tossing out 7 billion pounds of food a year in the U.S., according to ReFED, a nonprofit that aims to reduce food waste.

“Companies want to protect their image, but that might mean that more products are disposed of when they really are still healthy and consumable,” said Jonathan Allen, the director of graduate programs for food science at North Carolina State University. Infant formula is one exception, and you should not buy it or use it after its “use-by” date, per the USDA. 

The quality of your olive oil or can of soup after two years will depend on how you care for it, though, even if they may be safe to consume. 

“There’s going to be a lot of variability in terms of how you store it, how you treat it in your own storage, how it might have been affected during its own shipping and transport,” Roe said. 

That’s why manufacturers often overestimate how much the quality of their food will degrade when the “best if used by” date arrives.

“I think a lot of manufacturers will maybe have an ideal date and then slide it back so that they build in a buffer. So many times, those dates are going to be conservative,” Roe said. “Manufacturers want to make sure that you have a high-quality experience when you consume [their products].”

But products with faraway expiration dates are generally safe to eat beyond these dates, said Gregory Ziegler, a food science professor at Penn State University. With canned food, for example, you can likely still eat the product if the can is still intact, he said.  

Sometimes products will have a “sell-by” date, which is the manufacturer communicating with retailers, not consumers, Roe said. 

Is there a way food manufacturers can avoid confusing consumers? California passed a new law that requires manufacturers to standardize the language on their products. 

By July 1, 2026, food manufacturers will have to use the phrases “Best if Used by” or “Best if Used or Frozen by” to signal when the food will be at its peak quality. To signal when it’s safe to eat an item, they’ll have to use the phrases “Use by” or “Use by or Freeze by.” They can no longer use the phrase “Sell by.” 

“It’s an encouraging first step to bring normalization to the phrases that appear on date labels,” Roe said. 

Products sold in other states may end up adopting these same labels since a manufacturer that makes products for California is also probably producing for other states, Roe said. 

Roe said you should follow the dates when it comes to deli meats and soft cheeses, which have been linked to listeria outbreaks. But for shelf-stable items, you can use your gut. 

“Open it up, take a small taste, see if you still like the quality, and then go with it from there,” Roe said.