You're standing in your kitchen, holding a carton of eggs dated three days ago. Are they still safe to eat? What about that can of beans from last year? The yogurt that says "best by" yesterday? Every day, people throw away perfectly good food because of dates stamped on packaging—dates that most people don't fully understand.
Expiration dates seem straightforward: the food is good until this date, then it's not. But the reality is far more complicated. Most date labels have nothing to do with food safety. They're about quality, and they're largely unregulated. The system we rely on to know when food is safe is surprisingly arbitrary.
Understanding why these dates exist—and what they actually mean—can change how you think about the food in your refrigerator.
The Problem This Was Meant to Solve
Before date labels, consumers had no way to know how fresh a product was. A can on the grocery shelf might have been there for a month or a year—there was no way to tell. This created real problems for both consumers and retailers.
Consumers wanted assurance that they were buying fresh products. Nobody wants to pay full price for stale bread or old milk. Without dates, shopping required trust that stores were properly rotating their stock, and that trust wasn't always warranted.
Retailers, meanwhile, needed a system to manage inventory. Without dates, employees had no standardized way to know which products to pull from shelves. Some stores used coded dating systems—letters or numbers that meant something to staff but nothing to shoppers. This asymmetry made consumers suspicious.
Food manufacturers also had an interest in dates. If a product sat on shelves too long and degraded in quality, customers might blame the brand rather than the store. Dates gave manufacturers some control over how long their products stayed in circulation.
How It Actually Came to Exist
Open dating—dates that consumers could actually read—began appearing on products in the 1970s. There was no federal law requiring it; companies and stores adopted the practice voluntarily in response to consumer demand. The consumer movement of that era pushed for more transparency, and readable dates were part of that push.
The problem was that no one standardized what the dates meant. Different companies used different terms: "sell by," "best by," "use by," "best before," "expires on." Each had slightly different implications, but consumers treated them all the same way—as the date after which food becomes unsafe or inedible.
The federal government largely stayed out of it. To this day, the only product federally required to have a true expiration date is infant formula, because its nutrients degrade over time in ways that matter for infant health. Everything else is voluntary and varies by state.
Some states enacted their own dating requirements, creating a patchwork of regulations. A product might need a date in New York but not in Texas. The lack of consistency has persisted for decades, confusing consumers and contributing to massive food waste.
Why It Still Exists Today
Date labels persist because they serve multiple interests, even if imperfectly. Consumers feel more confident buying products with dates. Retailers have a system for stock rotation. Manufacturers can set expectations for when their products taste best.
The grocery industry has resisted standardization because current practices work well enough for their purposes. "Sell by" dates, for instance, are really instructions for stores, not consumers. They tell retailers when to pull products to maintain freshness, building in a buffer so consumers have time to use products at home. But consumers interpret them as expiration dates and throw food away prematurely.
"Best by" and "best before" dates are quality indicators, not safety dates. They're the manufacturer's estimate of when the product will be at peak quality. Food is usually still safe well after these dates—it just might not taste as fresh. But most people don't know this distinction.
The current system also drives sales. When people throw away food that's past its date, they buy more. There's an economic incentive not to clarify the confusion, even if it contributes to billions of dollars in food waste annually.
What People Misunderstand About It
The biggest misconception is that food becomes unsafe on its expiration date. For most products, this simply isn't true. Canned goods can last years past their dates. Eggs are typically good for weeks after their sell-by date. Dry pasta and rice can last indefinitely. The dates are about quality preferences, not safety thresholds.
Another misconception is that date labels are regulated and standardized. Outside of infant formula, there's no federal requirement for how dates should work. The terms used—"sell by," "best by," "use by"—aren't legally defined at the federal level. A company can put whatever date it wants on a product using whatever terminology it prefers.
Many people don't realize that date labels are often extremely conservative. Manufacturers set dates with wide safety margins to protect their reputation. A "best by" date might be set months before the product would actually decline noticeably in quality.
Perhaps most importantly, people misunderstand what determines food safety. It's not the date on the package—it's how the food has been stored. A product kept at proper temperature might be fine long after its date, while one left out on the counter might be unsafe before its date. Your senses—smell, appearance, texture—are often better indicators of spoilage than any printed date.
Expiration dates exist because we wanted more information about our food. But the system we got is confusing, inconsistent, and contributes to enormous waste. Understanding what these dates actually mean is the first step toward using them more wisely.