Lauren Saccone
July 02, 2017 10:02 am
Ross Gilmore/Getty Images for Kat Von D Beauty

Look, we get it. Makeup is expensive, and throwing it out can be physically painful (particularly when you’re in love with the color). But if you ignore your makeup’s expiration date, you do so at your own risk. Turns out that lipgloss you’ve been holding on to since high school is a breeding ground for gross bacteria. One brave Redditor did some research on the ugly truth behind makeup’s expiration dates.

Reddit user Semicolon_Expected was like many of us: They had makeup that was past its prime. Unlike most people, however, the Redditor decided to perform an experiment. They took petri dishes and swabbed the old makeup onto them to see what would happen. The results of this little test are actually pretty horrifying.

Take a look — if you dare.

After just three days, the results are clear: You can see tons of gross bacteria growing all over the sample. Although people in the Reddit thread stressed that this bacteria isn’t necessarily harmful (since it essentially came from the user themselves), it’s still pretty revolting.

Semicolo_Expected repeated the experiment with some downright ancient mascara, and you can guess what the results were.

If you have the sudden urge to purge your makeup cabinet, we’re right there with you. Here’s a handy guide on when to ditch your makeup. And on that note, we have some cleaning to do.

Advertisement