It’s the age-old trap: you’ve bought something YEARS ago, and you can’t remember when you bought it, or for how long you’re meant to keep using it.

What you may not know is that using a product well past its use-by date can actually cause your skin a lot of harm, in the form of breakouts, dryness, oiliness, etc.

So, how are you meant to know how long to keep a product for?

It’s actually pretty simple, and it’s something that’s usually on every beauty product, from exfoliators and cleansers to lipsticks and bronzers. Check the back of your product. Does it have a little icon that looks a bit like a jar of cream with a number on it? It might say 2M, 6M or 12M (or any number with the letter ‘M’ after it). Whatever it says, the ‘M’ stands for months. So if that crusty old lipstick from 2010 says ’12M’ on it, and you’re still using it, beware. You might just get a cold sore!

Don’t just wait for that product to start looking old for you to toss it out. Instead, I’m giving you a challenge: Gather all your beauty products (yes, cleanser and exfoliator included), and look for the little jar of cream icon. If you can honestly say it’s still within the use-by date, keep it. The rest, throw away! However, this use-by date is only applicable if you’ve already opened the product. If you’ve yet to open it, it’s okay.

Let me know in the comments how you go!