Food in your pantry and refrigerator do have expiration dates. Make it routine to periodically check the refrigerator and pantry for food that is passed its expiration date and discard it. You don’t want kids or guest to accidentally eat something that has already expired.
Checking the expiration date of packaged foods is the first start. In regards to other meats, fruits, and vegetables, it becomes more a matter of smell and visual clues when certain foods have gone bad. Being diligent on these tasks will help keep the family safe from food borne sickness.
Here is a good overview from Howcast on how to review what foods have gone bad.