The 2:4 rule is simple: store leftovers within two hours and consumed the leftovers within four days. Leftovers shouldn't sit out at room temperature longer than two hours or the risk of food contamination starts to grow. And four days in the refrigerator ensures against food spoilage. Can you push both of these limits a little? Sure.
• Read more: How Long Do Leftovers Last? at Real Simple
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