You’re sitting at your desk, watching the clock tick away, getting yourself ready to bolt out that office door the second it strikes 5 p.m. You are tired, and you’ve been struggling to stay awake all day, focusing only on how fast you can get home and crash into bed.

We’ve all had those days, weeks, or months when work piles up, projects are never-ending, and our sleep is paying the price for it. But what happens to our bodies when we don’t get enough sleep?

Here are some interesting facts about how sleep deprivation effects our body and health, according to Self.com.

First, your brain will feel fuzzy. You might find it difficult to remember things, put sentences together, or even focus on something for an extended period of time.

Next, you might notice that your mood is all over the place. When you don’t get enough sleep the brain sends out neurotransmitters and other hormones that help keep you awake. As a result, you might start to feel manic. You will notice your emotions start to become irrational, and that’s because your brain can’t tell what’s important and what isn’t. So something very little, like not getting the last donut in the break room, can feel like the end of the world.

Speaking of donut, you might notice you have cravings, and mainly for greasy food. That’s because your brain is not sure when to be hungry or not. You’ll want to snack a lot, but because you’re sleep deprived, your metabolism will slow down. Not a good combination.

As if that isn’t bad enough, you’ll begin to physically look tired as well. Your skin color won’t look healthy, you’ll get bags under your eyes, and conditions like psoriasis can worsen….

Because your immune system weakens. Yup, lastly, your immune system begins to be compromised because your body does all of its repairing when you sleep. You’ll find you have a harder time fighting off the common cold, and you might notice that you feel sick all the time.

Feeling like taking a nap yet? Go get some shut-eye!