The science of saline – why can we drink pure water, but when we put water into our bodies in other ways, like an IV, must we add minerals to it?

Question

The science of saline – why can we drink pure water, but when we put water into our bodies in other ways, like an IV, must we add minerals to it?

In: 480

Answer 1

In short, we can’t drink pure water either. Our bodies rely on electrolytes to function properly, and drinking ultra pure water would sponge those electrolytes out of your blood. Even filtered drinking water, which we would think of as “pure” contains enough trace elements of electrolytes to make it safe to drink.

[The TV show QI did a bit on this.](https://youtu.be/Ra0vcC476Rk)