Water Q&A: Why can't people drink seawater?

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Find out why the salt in seawater is toxic to humans.

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Why can't people drink sea water?

Water Questions and Answers

Seawater is toxic to humans because your body is unable to get rid of the salt that comes from seawater. Your body normally gets rid of excess salt by having the kidneys produce urine, but it needs freshwater to dilute the salt in your body for the kidneys to work properly. Normally that is not a problem, as you are always drinking water and eating food with water. Tissue in your body also contains freshwater that can be used. But if there is too much salt in your body, you kidneys cannot get enough freshwater to dilute the salt and your body will fail. 

► Find out more about saline water.