According to national regulations, the shelf life of salt is three years. But in fact, the shelf life of salt can be exempted. If trace elements such as calcium, iron, zinc and selenium are added to the salt, the shelf life needs to be marked. When storing, pay attention to moisture and light. Try to eat while buying, and don't buy too much at a time.

The unopened edible salt can still be eaten if it is preserved for three years, but if it is preserved for three years, it is best not to eat it. After all, salt is not very expensive. It's best not to eat salt that has been stored for more than three years, because some other trace elements will be added to the salt now, which will affect the shelf life of the salt.