If you're following the South Beach Diet — which emphasizes nutrient-rich, high-fiber fruits and vegetables, lean meats, and low-fat dairy products — you may be purchasing more fresh foods than you had in the past. "Use by" and "Sell by" dates may be stamped on your groceries, but what do these terms mean?

Below is a list of typical labeling terms — with their definitions — to help you figure out how to decipher the dates stamped on your fresh foods:

 

• Best if used by (or use by): This is the date by which you should aim to use the product, but be advised that this date does not indicate when a food will spoil. Manufacturers voluntarily place this date on the packaging as a general guide. Most foods are okay to consume for about two days after the use-by date but may be lacking in flavor or freshness. Of course, if you notice any signs of spoilage, such as an obvious odor or mold, play it safe and assume the food has spoiled.
• Sell by: This date is for vendors — not consumers. The sell-by date is meant to notify your grocer to pull the product off the shelf. While you shouldn't purchase foods beyond their sell-by dates, foods past their sell-by dates are not necessarily spoiled. If the product has remained unopened and there aren't any signs of spoilage, it may still be okay to eat.
• Expiration: Just as the word indicates, this is the date on which a food is expected to spoil. You should not consume or taste foods past this date. Eggs are one important exception — they can typically last an additional month past the expiration date as long as they're kept properly refrigerated.

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