If you’ve attempted to read the dates on food labels in the past and failed to understand the information, then you’re not alone.

According to a new report co-authored by the Natural Resources Defense Council (NRDC) and Harvard Law School’s Food Law and Policy Clinic, more than 90 percent of American may be prematurely tossing food because they misinterpret food labels as indicators of food safety.

In a September 18, 2013 press release, Dana Gunders, NRDC staff scientist with the food and agriculture program said “expiration dates are in need of some serious myth-busting because they’re leading us to waste money and throw out perfectly good food, along with all of the resources that went into growing it.”

Gunders also noted that phrases like “sell by,” “use by,” and “best before” are misinterpreted and lead to a false confidence in food safety.

“Sell by December 24” is a type of information you might find on a food product. Are dates required on food products? Does it mean the product will be unsafe to use after that date? The answers to these questions will be revealed as we demystify the dates on the food label.

There are two main categories of dating that exist – “open dating” and “closed or coded dating.”

“Open dating” uses a calendar date as opposed to a code and helps the store determine how long to display the product for sale. It also helps you know the time limit to purchase or use the product at its best quality. It is not a safety date. After the date passes, while it may not be of best quality, refrigerated products should still be safe if handled properly and kept at 40 °F (4.4 ºC) or below for the recommended storage times listed on the Refrigerator/Freezer Storage Chart. In addition to the “open dating”, there must be a phrase such as “sell by,” or “use by” to explain the meaning of the date. You’ll find “open dating” primarily on perishable foods such as meat and dairy products like milk and yogurt.

“Closed or coded dating” are packing numbers found primarily on shelf stable products like cans of soup and boxes of macaroni and cheese.

 “Sell by” dates are a tool for stock control, suggesting when the grocery store should no longer sell products in order to ensure the products still have shelf life after you purchase them. It’s best to buy the product before the date expires and cook or freeze the product according to the times on the Refrigerator/Freezer Storage Chart.

“Best if used by” date is recommended by the manufacturer for best flavor or quality. It is not an accurate date of spoiling or an indication that food is unsafe. Even if the “best if used by” date has passed, your food should be safe if stored and handled properly.

“Use-By” date is the last date recommended for the use of the product while at peak quality. The date has been determined by the manufacturer of the product and is not a safety date.

Even if the “use by” or “sell by” date hasn’t passed, foods that are mishandled can be contaminated by foodborne bacteria that can cause illness.

You will want to follow these tips to ensure food safety.

  • If perishable, take the food home immediately after purchase and refrigerate it promptly. Freeze it if you can’t use it within times recommended on Refrigerator/Freezer Storage Chart.
  • Once a perishable product is frozen, it doesn’t matter if the date expires because foods kept continuously frozen are safe indefinitely.
  • Always wash your hands.
  • Separate raw foods from ready-to-eat foods
  • Follow handling recommendations on the product and cook to proper temperatures

Still have questions regarding food safety? Download the free “Is My Food Safe?” app where you will find answers to all of your food safety questions like: Is it Done Yet? Time to Toss? and Is My Kitchen Safe?

And remember, if you still aren’t sure how old something is or if it is safe to eat: When in doubt, throw it out!

Constance Brown-Riggs, MSEd, RD, is an award winning registered dietitian, certified diabetes educator, and national spokesperson for the Academy of Nutrition and Dietetics. She is the author of The African American Guide To Living Well With Diabetes and Eating Soulfully and Healthfully with Diabetes. Follow Brown-Riggs on twitter @eatingsoulfully.