A 19-year old South Carolina man died as a result of eating a batch of pancakes from an expired mix. It wasn't exactly the pancakes that killed him, though. He seems to have had an allergic reaction to a mold that grew in the mix.
As unfortunate as this story is, it can illustrate a valuable point to everyone about checking expiration dates, especially on things that have a long shelf life. While the ingredients, which in the case of pancake mixes consist primarily of flour, can last for a long time in a cool, dry place, unwanted things can develop over time. Sometimes a product can smell or look "off, though a potential problem may not be obvious to the naked eye. "Unseen molds can trigger both minor and severe allergic reactions, so it is best to throw out an old mix than to risk anaphylactic shock - especially if you are prone to allergies.
Update: Link is now fixed
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