Even when you feel like a total greaseball, you (and all the human beings around you) are still 55 to 60 percent water. Our blood, brains, and hearts are almost 75 percent water, our lungs are 83 percent, and even our bones are almost one-third H2O. Staying properly hydrated is necessary to keep a body working in tip top shape, but what happens when you get too little or (yes, it's possible) too much? In short, it’s not good.

In the TED-Ed video below, Mia Nacamulli and animator Chris Bishop dive into the issue of humans and hydration. We need water for things like lubricating joints and regulating temperature; each day, we lose 2 or 3 liters from just existing in the world. When we don’t get enough water, our brains shrink and our bodies have to work harder. When we have too much, our cells swell, and it can even lead to death in extreme cases.

The myth of eight glasses a day arose sometime in the mid-20th century, and while it remains a source of endless debate, the biggest takeaway might be that there’s simply no right answer when it comes to hydration because (gasp) everyone is different. Your recommended daily water consumption depends on things like health, level of activity, weight, age, and environment.

To get your fill of hydration facts, watch above and get the full TED-Ed lesson here.

Banner image via TED-Ed // YouTube