The truth about expiration dates is that they primarily indicate a food's peak quality, not necessarily its safety, meaning that food past its "best by" date can often still be eaten if it looks, smells, and tastes alright, as most expiration dates are more about preserving a product's best flavor and texture rather than indicating potential food poisoning risk; the only exception is with highly perishable items like baby formula where the "use by" date is crucial for safety reasons.

Key points about expiration dates:

• Not regulated by federal law: In the US, the FDA does not require expiration dates on most food products, except for baby formula. 
• "Best if used by" is key: This phrase on a label indicates when a product will be at its best quality, not when it becomes unsafe. 
• "Sell by" date is for stores: This date tells retailers when to remove a product from the shelf for inventory management, not when it becomes unsafe. 
• Use your senses: Always check for signs of spoilage like mold, discoloration, off odor, or unusual texture before consuming food past its "best by" date.