Edit: Question answered. Thanks!
Don’t be too hard on me, I almost failed chemistry:'(
In: 2220
> Aren’t they both water + salts?
Yes, but VERY different amount of salts. The sports drink has a pretty low salt concentration. Just enough to replenish the salt lost by your body by sweating. Sea water contains many times more salt per volume, and is much saltier than your body itself. It’s so salty that when you drink it, your body has to use up its *existing* water trying to dilute the salt enough to pee it out before it kills you by frying your nerves (nerves use salt to send signals, so getting flooded with salt messes them up).
It comes back to the classic saying “**the dose makes the poison**”, which just means “anything is toxic if you consume enough of it”. Heck, even plain water by itself is toxic if you drink too much. Eating some salt on your pasta is fine. Eating a pound of salt out of the bag is not. Seawater is much like option 2 there. **Only about 13L (3.5 gal) of seawater contains a** ***pound*** **of salt.** That’s only a few days’ worth of water-drinking. Imagine eating a pound of salt in a couple days. That’s why seawater isn’t drinkable.
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