sea water

can anybody please tell me why drinking seawater is bad in terms of the kidney.
i have thought for ages and cant think of a reasonable explanation.
many thanks!

Reply 1

shinyhappy

Can't really think why it would be bad for the kidney, specifically. I guess though, that drinking a lot of it would have the same negative effect as drinking large amounts of any isotonic drink. Because the hypothalamus doesn't detect a change in water potential, it will still cause the body to release some ADH, so we'd swell up, if we drank enough. Body fluids have the same salt concentration as sea-water, (something to do with us evolving from fish.) Maybe the excess volume of water/salt in the blood would damage the kidney?

Reply 2

space_aura

ok i phrased that badly.
why is it bad for you generally.
what i mean is i dont mean sickness, i mean in terms of dehydration
thanks

Reply 3

shinyhappy

space_aura

ok i phrased that badly.
why is it bad for you generally.
what i mean is i dont mean sickness, i mean in terms of dehydration
thanks

well, from what I understand (may be wrong) it wouldn't dehydrate you. Its the same concentration of the fluids in your body, so it doesn't change them. If there is no change, the body will not expel any extra water - ergo, you'd swell up, not get dehydrated.
This is a fairly null point though, as you'd have to drink pints of the stuff to have this affect, and most seawater would be really polluted, and so wouldn't be the same as body fluids.

Reply 4

Stranded

Hmm well I take a guess...
Sea water is salty right? So perhaps concentration of salts is too high in the water you're drinking, which will plasmolyse our body cells ( according to the rules of osmosis) & hence you feel dehydrated?