Issue No. 124: Will this expired yogurt/tin of tuna/[fill in the blank] kill me?

Are foods past their expiration dates unsafe to eat?

Probably not. The dates printed on foods—whether they are labeled as “sell by,” “best by,” “use by,” or any other variation on the language—have very little to do with safety, or even when the food will “expire.” Instead, the dates are determined at the whim of the food’s manufacturer, as their best guess as to when the food will be past its peak quality level. What is the “peak quality level”? Whatever the manufacturer thinks it is.

Does the government require foods to have dates printed on them?

No. With the exception of baby formula, the federal government does not require any foods to be printed with any sort of expiration dates. State laws vary widely, and many states don’t have any laws about food labeling or require labels on only certain foods, like shellfish.

If expiration dates are often meaningless and not requires, why print them at all?

A century ago, when we all grew our own food or bought it from our neighboring farmer or corner grocer, we didn’t need dates on our foods; we knew how fresh it was. But throughout the 20th century, as the agricultural system got bigger and food eaters bought more packaged foods and thus became more removed from food growers, we lost that knowledge. How could we be sure that what we were buying wasn’t stale or spoiled? By the 1970s, a growing demand for clear indicators of freshness resulted in the piecemeal development of various dating systems.

The printed expiration dates stuck around. Consumers liked them because they felt they had more insight into their foods. But perhaps more significantly, manufacturers liked them, too. By being conservative with the dates they print, they can subtly convince consumers to buy more food. A recent survey reported that 91% of us have thrown out food because it was past its printed expiration date, and data shows that the average US household throws out 15-25% of all the food they buy annually. If our food “expires” and we have to replace it, that means more sales for the manufacturer—and less money left in our own pockets.

Does that mean you should completely disregard all expiration dates? Instead, I’d recommend taking them with a grain of salt. They can still sometimes be a useful tool for reference. For instance, we print “eat by” dates on all of our pastries. We bake them without any preservatives, just like you would at home. So, just like how a scone you bake from scratch in your own kitchen will start growing mold after a couple of weeks, our scones will, too—and we want you to get to enjoy them before then! But that’s the important point: ultimately, it’s the mold—not the date we print—that determines whether a pastry is still good to eat. The date is just a tool to hint at when that might be more likely to happen.

For a good list of how long to keep all sorts of foods ranging from eggs to flour to soy sauce, check out J. Kenji López-Alt’s article “The Food Expiration Dates You Should Actually Follow.”

So how do I know if a food is safe to eat?

Trust your eyes, nose, and mouth! Humans have been eating food for millennia; we’ve only been printing expiration dates on foods for a few decades. For most of human history, we’ve judged for ourselves if food was good to eat. Look at it: do you see mold growing on it? Smell it: does it have an off-putting aroma? Try a tiny nibble: does it make you want to retch? If you answered yes to any of these questions, then don’t eat it! But if it looks, smells, and tastes fine, it probably is.