Here’s something that would’ve saved a lot of people a lot of grocery money: ‘best by’ and ‘best if used by’ dates aren’t expiration dates. They’re quality dates. The manufacturer is basically saying, ‘this is when we think it’ll taste the best’ — not ‘this is when it becomes dangerous to eat.’
As food safety expert Donald Schaffner from Rutgers University explained to NPR, after that date passes, ‘the food may not taste as good, but it’s still safe to eat.’ That’s a huge distinction when it comes to the labeling system.
PBS NOVA puts it simply: best before dates are about taste, texture, and appearance. Expiration dates — which are a different thing — are about safety. Most labels you see at the grocery store are the first kind, not the second.
The one date that carries more weight is ‘use by’ — and that one’s different. According to the Institute of Food Technologists, ‘use by’ is intended for highly perishable products that may have a food safety concern over time. So if something says ‘use by,’ take that one more seriously, especially for meat, seafood, and dairy.
For shelf-stable items like chips, cereal, or canned goods with a ‘best by’ date from last week, you’re almost certainly fine. For refrigerated foods like yogurt or leftovers, use your judgment — but know that your senses aren’t a perfect safety test. Some harmful bacteria don’t change how food looks, smells, or tastes at all. When in doubt with perishables, especially meat or fish, it’s safer to toss it.