We often throw makeup on our faces without a second thought. In fact, very few people actually pay attention to makeup expiration dates, which can lead to disastrous consequences. Makeup products can go bad as fast as the milk in your fridge, and while it is a waste to throw away half used products, it's much better than using expired toxins on your skin! Using expired makeup products can lead to breakouts, skin rashes, and irritation. And unlike many things you'll find in the kitchen, makeup usually doesn't come with expiration warnings, so it's good to know when to use and when to throw away.
Sometimes, you'll find products that have symbols of open lids and a number/ letter. If the number is 12, for instance, that means it'll expire 12 months from the day the product is opened.