Americans waste $640 of food each year, according to a new survey released by the American Chemistry Council. That uneaten or unused food may end up in the garbage in part because consumers are really confused by expiration dates; one British study suggests that misinterpreting expiration dates is responsible for 20% of food waste.
While many people think “best by” or “sell by” dates are indicators for food safety, the reality isn’t as clear cut.
Expiration dates and food labeling emerged during the 20th century as Americans increasingly stopped making their own food but still wanted to know how fresh it was. According to a 2013 report from the Natural Resources Defense Council (NRDC) and Harvard Law School’s Food Law and Policy Clinic (FLPC), many Americans think their food is unsafe if the date they see on the label has already passed. However, these dates are not indicators that the food will make you sick; they only indicate when they are considered still fresh. Eating refrigerated food slightly past its prime may not taste as good as eating it fresh, but in most cases, it’s not going to harm you, according to the report. (And you might be surprised how long foods do last in the fridge.)
Here’s what those labels really mean:
“Sell by”: This date only indicates when the manufacturer suggests grocery stores should stop selling the product. It’s a way for companies to make sure their food is being sold when they determine it’s at the best quality.
“Best by” or “Best if used by” or “Use by”: Similar to “sell by”, this label marks the maker’s estimate of when the food will no longer be at its freshest, highest quality. It doesn’t necessarily mean you’ll get sick if you eat it after the date, nor is it a guarantee that the food has even gone bad. Consumers may not notice a difference in quality.
None of these labels is actually an indicator of food safety; often, the date on the packaging and when the food may actually be no longer safe to eat don’t match up. For instance, raw shell eggs can last in the refrigerator for up to five weeks, according to FoodSafety.gov—which may be longer than the date stamped on the carton.
To keep your food safe, it’s important to make sure that refrigerated food doesn’t spend too much time in warmer temperatures, which make it more susceptible to bacteria growth. Certain foods like “ready to eat” dishes, infant formula and baby food should be consumed promptly.
Public health experts, like those at the NRDC and FLPC, argue better labeling that more accurately reflects spoiling dates would not only mean safer food consumption, but could also cut down on food waste. If labels could differentiate between safety and quality, it would be a much more useful system to consumers, the groups say.
To look up the shelf life and refrigerator life of your foods, try the Foodkeeper storage guide, a collaboration between the Food Marketing Institute at Cornell University and U.S. Department of Agriculture.
Read Next: Americans Throw Away $640 Worth of Food Each Year
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