Decoding Food Expiration Dates: What You Really Need to Know

How often do you check the dates on items in your refrigerator? For example, your yogurt might still be good for several days, while the barbecue sauce bottle shows a “best before” date that passed last Sunday. Is it still safe to consume?

The reality is more nuanced. Most food date labels indicate peak quality rather than safety. In the U.S., there are about 50 different types of date labels, such as “use by,” “sell by,” and “packaged on,” which primarily signal when a product’s freshness or taste may begin to decline.

While it’s important to heed these dates for certain items, confusion over labeling contributes to roughly three billion pounds of food being discarded annually, according to a food waste advocacy group. Notably, infant formula is the only product with federally regulated, standardized date labels, leaving many consumers uncertain about when to discard other perishable foods.

Here is what consumers should understand about food expiration dates.

In the early 20th century, as American households shifted from relying on locally sourced foods to processed and packaged products, manufacturers began adding date labels to address concerns over freshness. However, these labels only became widespread during the 1960s and 1970s, alongside broader efforts to improve nutrition transparency.

Currently, the responsibility for determining date labels lies with individual food manufacturers, each applying their own standards. According to food science experts, some companies use mathematical models to predict when a product’s quality diminishes, while others perform specialized tests involving exposure to higher temperatures, humidity, or oxygen.

Certain producers may even test products by exposing them to mold, yeast, or harmful bacteria such as E. coli or salmonella to estimate shelf life. Meanwhile, smaller companies with limited resources might base their dates on competitors’ labeling practices rather than conducting extensive testing.