when is it ok to drink seawater or urine

Watched “Man vs. Wild” on Discovery last night. He was out in the Australian Outback and essentially out of water; so to help prevent dehydration he drank his own urine. I don’t trust his survival techniques implicitly because I’ve seen him make mistakes and “cheat” a couple of times.

Now, I was under the impression that drinking urine or seawater, would actually make you more dehydrated because salts require more water to flush from your system. Yet I could see that if you need fluids now, and you aren’t going to be drinking this exclusively, and you have promise of fresh water in the near future; it might be better to drink your urine or seawater.

My question is: Under what circumstances would it be advantageous and life saving to drink this stuff? (i.e. do it if you know you will die in a couple hours without it; or if you know you can get fresh water in half a day)

From reading previous threads here, I gather that it’s never appropriate to drink seawater, and in all cases you would be better off not drinking anything at all than drinking seawater. Just what I’ve gathered from previous topics here

My understanding from reading a number of survivor accounts is that drinking either seawater or urine is self-defeating, as a means of prevent dehydration: Both are usually of such a high osmotic content that to properly dispose of them your system will pull water from your body to allow them to be discharged, so to speak.

When you are out of food and have already gone four days without water?

That was my understanding, though this article from Wikipedia seems to contradict me on urophagia.

Drinking urine (especially your’n) is a whole lot safer than drinking seawater, but I don’t know how much would be safe.

Wasn’t there some guy about fifty years ago who wanted to prove his theory that drinking seawater if you were already well-hydrated to begin would indeed sustain you over several days? While it wasn’t especially good for you, he believed the main reason drinking sea water was usually so disastrous was because people who were only severely dehydrated usually ended up drinking it.

If I recall correctly, he drank it for 4 or 5 days. By the end, his health had understandably deteriorated, but he didn’t die.

In extremis, one could recycle wastes by building a solar type still with a sheet of clear plastic. Not very tasty but better than piss. Any latent water in the soil will condense too, and putting cut vegetation along with helps even more. Supposedly (I have not tried it) 2 or 3 such stills will often produce enough water to last almost indefinitely. But you gotta have sheets of preferably clear plastic along.

Common Tater, that also means that you’re willing to stay in place to continue getting the benefit from your still. Unless I were sure of rescue coming in a reasonable time, I’m not sure I’d want to trade that supply of water in exchange for my mobility.

If Alton Brown of Good Eats fame can be believed, you can stretch your supply of drinking water by adding saltwater to it. From here:

Assuming that the above is correct, I guess if you knew the salinity of your pee (and doesn’t everybody?) you could do the same with urine.

I think it’s “piss goes with seafood, seawater with beef”, but most food experts today suggest you can serve whatever you want.

Cecil on drinking urine

Dex on drinking seawater

In the latest (or a recent) issue of National Geographic’s Adventure magazine there is a quiz you can take testing your knowledge about surviving under certain circumstances. One of the questions regarding desert suvival was “How many days without water should you go before drinking your own urine?” The answer was “one.” I guess when faced with the prospect of dehydration and drinking water is scarce, such as it is in a desert or in the sea, one shouldn’t, um, piss around. Bottoms up lads.

“What is, how would you describe a Cosmopolitan, Alex?”.

But if you were diabetic and had just come off a cotton candy bender…

If the vegetation consists of shrubs or trees, you can just tie a bag over a (living) leafy branch - the water transpired by the leaves will condense in the bag.

The above mentioned National Geographic suvival quiz mentioned this as being the fastest method for obtaining fresh water.

Instead of drinking the urine, is it better to use the rectum to act as a filter to absorb water?

This was my understanding as well, as I’ve posted before, based on my reading of Nathaniel Philbrick’s In the Heart of the Sea. He stated, that while not ideal, a solution of 3 parts fresh water and 1 part seawater could be used to stretch out one’s supply of drinking water. He also stated that drinking urine, while not hugely harmful, really wasn’t beneficial in any way either.