It’s Friday and you found out that you aced that math quiz you took earlier that week. You’re really proud of yourself and you decide that, despite trying to watch what you eat, you will reward yourself with some candy.

You count your quarters to make sure you have enough change for that trip to the vending machine and decide to get a package of peanut butter cups—one of your weaknesses. You get back to your dorm room, prize in hand, and throw your backpack on your bed.

Maybe you’re a little overexcited as you open the package or maybe you’re just a klutz. But as you pull open the wrapper, one of the peanut butter cups falls to the tile floor. Crap!

You’re certainly not going to throw away such a delicious treat, so you pick the peanut butter cup off and you obeyed the “five-second rule,” so it’s okay to eat something that fell on the floor, right?

You ponder this as you take a bite of that hard-earned candy.

A study conducted found that the five-second rule is not just an old wives’ tale or a myth. The study concluded that the longer a food sits on the floor, the more bacteria it will be contaminated with.

That in itself seems like a no-brainer, but the study also discovered that the types of food and floor-too. For example, dry foods like cookies were less likely to attract bacteria than wet and sticky foods. Dropping foods on carpeted floors was also found to be “safer” than dropping food on laminated or tiled surfaces.

The study also found that women were more likely to eat food that had been dropped on the floor, although 87 percent of all people would eat or have eaten food dropped on the floor.

So if you ever find yourself starring down at a morsel you just dropped on the floor, just know that the chances are, it’s safe to eat.