Except for a few items, neither the government nor industry regulates dates on food products. That means it’s up to the manufacturers and the grocery stores to create the dates and follow them. "There is no uniform or universally accepted system used for food dating in the United States. Although dating of some foods is required by more than 20 states, there are areas of the country where almost no food is dated," according to the USDA.

In Wisconsin, food product dating is required for three items:
 

• Infant formula is regulated because it’s for a very vulnerable population and is their only source of nutrition. The date on the formula container is an expiration date, which means it should be used or discarded by that date and would be illegal to sell after that date.
• Smoked fish is not cooked before being eaten, so it’s regulated to prevent bacteria growth. As for the infant formula, the date is an expiration date, so it shouldn’t be sold or consumed after that date.
• Eggs have a packing date, but the date consumers see can be one of several choices – an expiration date, a sell-by date (no more than 30 days after packed), a use-by date or best-if-used-by date.

Still, even if you check the date on the food you purchase, the food might not be safe. "You can buy the nicest, freshest food product on the shelf," said Donna Gilson, a spokeswoman for the Wisconsin Department of Agriculture, Trade and Consumer Protection. "But if you don’t take care of it at home, it’s not going to be safe."