We already know that fast food isn't great for us. But sometimes you just need it. Whether it's because you're in a rush or simply because you like it and #TreatYourself, sometimes you just have to have fast food.

But thanks to a Reddit thread that asks: "Fast food employees of Reddit, what shouldn't we order?" we learned all fast food is not created equally.

So, next time you have a massive french fry craving, here's what to avoid.

"I'll just come back."

It's early in the morning, you were rushing around and didn't have a chance to eat breakfast and now you have five minutes before you have to get to work and you're starving. In the distance you see a Taco Bell and think "I'll just go there".

Well, don't. __PM_ME_ANYTHING warns against ordering "anything from Taco Bell within the first hour of opening," because "it's all carried over from the night before".

Not good.

"I'm really hungry, I'll have the small."

_psychedalek_'s boyfriend works for burger chain Five Guys and she says their fry sizing is misleading. "Five Guys' fry cups are deceivingly small, but you always get an 'extra scoop' or two of fries with your order," she explains. "You basically always get double the fries than you think you're going to get based on the fry cup's size. If you don't factor in the 'extra scoop(s)', you'll end up spending way more money on fries and getting too many."

"On second thought, I'll just have turkey."

While the thought of ordering seafood at a Subway wouldn't cross most people's mind, TrogueJames felt he should worn us all anyway. He said to never order a Seafood Sensation Sub at Subway because they're "hardly ever ordered so the seafood mix is often kept out for maximum allowed time before being thrown away." In another comment he said that in the almost year he worked at Subway, he never tried it because it smelled so bad.

"No ice please."

It's not just the food though. Mysterious_baker writes, "Get your drinks with no ice. Can't tell you the number of ice machines I've seen with mold and dead flies in the bottom."

Or maybe take Redditor redjarmin's advice and don't order anything at all.