If you're dying of thirst in the desert, drinking your urine won't help you. The proteins and salts are by that point so concentrated that the body needs to pull fluid from the tissues to dilute them, which puts you back where you began, only worse, because now you are saddled with the memory of drinking your own murky, stinking pee. Rhabdomyolysis
In Mary Roach's book "Grunt: The Curious Science of Humans at War," she illustrates a critical survival challenge in desperate situations, such as being stranded in the desert. The act of drinking urine in such conditions is counterproductive. Instead of providing hydration, the high concentration of proteins and salts in urine forces the body to draw fluid from its own tissues, worsening the state of dehydration.
This vivid example emphasizes the...
