By Amy Feldman

By Amy E. Feldman

PHILADELPHIA (CBS) – What’s the difference between a sell by date, a best if used by date, and a use by date?

If the thought of eating food past its expiration date makes you turn green, that might be the reason that researchers estimate Americans throw away more than $2000 worth of food every year – but that might be because they don’t understand the label.

According to the USDA, only infant formula must, by federal law, carry a calendar date to tell a store how long to sell an item. For other food products that have a calendar date displayed, that date must have a phrase next to it explaining the meaning of that date.

In general, the phrases will say “SELL BY” – which tells the store how long to display the product for sale. You should buy the product before that date, and then use or freeze it by that date once you take it home. You may also see the phrase “BEST IF USED BY” which is what the manufacturer recommends for best flavor. It is not a purchase or a safety date.

A “USE BY” date is the last date recommended for the use of the product at peak quality but it doesn’t mean that it’s unsafe if used later.

In any event, sometimes poor refrigeration or handling will cause a product to go bad even if the date hasn’t expired – so if the product smells bad or has turned green, don’t eat it unless you want to turn green too.

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