Why Can't Humans Drink Seawater?

This video talks about how osmosis causes changes in water levels inside of cells and helps us better understand the reason why humans can't drink salt water.

 

The Rime of the Ancient Mariner - Samuel Taylor Coleridge

"Water, water, everywhere,
And all the boards did shrink;
Water, water, everywhere,
Nor any drop to drink."

Osmosis is the movement of water into or out of cells.  Salt water actually causes cells to lose water.  So if you were to drink too much salt water, you could actually die from dehydration.

Read more about this from NOAA.

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