Did you ever throw out a dozen eggs just because the carton said they were a few days past the expiration date? Have you tossed a box of uneaten onion soup mix for the same reason? Chucked an outdated can of corn?

Then, like almost 90% of Americans, you have thrown away your food unnecessarily — and your money, too. According to a study from the Natural Resources Defense Council and Harvard Law School’s Food Law and Policy Clinic, most expiration dates are confusing for consumers. Worst of all, they cause us to get rid of food that would be perfectly acceptable to eat — and which would not cause us any harm.

“There is a lot of confusion around expiration dates, and we think they are a significant contributor to the needless wasting of food,” says Dana Gunders, who was the leading expert on food waste for the NRDC at the time of the study. She estimates that most households throw out hundreds of dollars worth of food every year. And it’s not just a problem in the United States.

“A study in the U.K. found that about 20% of food thrown out in households is because of this confusion or misinterpretation of the expiration date,” she says. The report urges the food industry and the government to create a clearer, user-friendlier food-dating system to help consumers. Their recommendations include eliminating expiration dates altogether.

In the meantime, how can you safeguard your family’s health while at the same time avoid throwing out perfectly good food? Here are some things to consider:

Contamination versus spoilage

There is a difference between the two. Yes, some foods will go bad if they are left uneaten for too long. But the likelihood is very low that an egg that is kept in the refrigerator for a couple weeks past its expiration date will be contaminated. If the food is well past the date stamped on it, Gunders says, before throwing it away, at least open it, sniff it, and taste it. If all of those things seem right, then go ahead and eat it. Important exceptions: meat, poultry, and prepackaged perishable foods like sandwiches and salads. These are health risks.

But know that most foods won’t make you sick because they were on the shelf too long. “When you hear about outbreaks of E.Coli or salmonella, that’s usually because of a pathogen that got on the food early in production. That’s a different situation than milk that goes through a natural process of decay. Your milk will smell or taste bad long before it will make you sick,” Gunders adds.

Temperature matters more than dates

After shopping, take your food home promptly and put it away immediately. “The temperature of food is more relevant than its age,” Gunders says. “If you leave something in a hot car for a few hours, it allows the growth of bacteria and then it becomes unsafe to eat.”

Know the definitions of labels:

“Sell by”

When you see that date stamped on your food, it’s intended to help the store know when to remove it from the shelves, so that the manufacturer can measure how quickly their products leave the shelves.

“When the product says ‘sell by,’ I want to say you can almost ignore that. It’s meant for the grocery store,” Gunders says. “It absolutely does not mean that the product is unsafe and nine out of 10 people are throwing product away based on that date.”

The Harvard/NRDC report recommends that the date somehow be hidden from consumers because it doesn’t help us to eat fresher food.

“Use by” and “Best by”

These dates are put on products by their manufacturers but surprisingly, they are not warnings about when the food will go “bad.” Rather, they are a suggestion of when the food is at its peak quality. But Gunders says, “According to our experts, 80% of the dates you see on products are guesses” about when the food will taste best. “It’s just a suggestion for the product’s peak quality, but it doesn’t mean it isn’t good after that date. There is no legal guidance involved in coming up with this date,” she says. “If everyone understood that these dates are just guesses, everyone would be taking them with a much larger grain of salt.”

But Gunders says you should be vigilant about following the freshness dates on prepackaged, ready-to-eat foods, such as a sandwich or salad with meat on it. If these foods hang around too long, they can become covered with a bacteria called listeria which actually multiplies in the refrigerator.

See Also: 9 foods that you should never freeze