4 ms·

Did he (or they) happen to mention the ratios of salt water to fresh? I don't know a whole lot about this topic, but I do recall reading somewhere that thirsty

Did he (or they) happen to mention the ratios of salt water to fresh? I don't know a whole lot about this topic, but I do recall reading somewhere that thirsty seafarers who succumbed to the urge to drink seawater ended up dying more quickly. I wonder if they figured out how much was okay to drink before it started negatively impacting health.

pilsetnieks 9y ago
The negative impact is due to water loss via vomiting or diarrhea, and thus having a negative water balance. It's not like saltwater in itself kills you. In fact, you could drink the water of some less salty seas, e.g. the Baltic Sea.
- int_19h 9y ago
  The real bad impact is from disrupting the way your kidneys work. Basically, seawater has a higher concentration of salt than it is possible for your kidneys to remove via urine (due to the physics of that process). For one thing, your body will try to use its existing water supply to flush the extra salt, which means that you'll be urinating (= dehydrating) more than usual. Once that's all gone, and seawater is the sole source for water in your body, your body will no longer be able to produce urine to carry the usual toxins out. Eventually your kidneys will fail. Although in practice, you will feel like a wreck both physically and mentally long before then, and given that people in a situation where they can only drink seawater generally have other dangerous conditions to deal with, these debilitating effects can well kill you before that. This also explains why diluting seawater is potentially viable - so long as you keep the salt concentration below the level your kidneys can handle, you can keep them working normally.
  - jaggederest 9y ago
    But the entire article is about the body using metabolic water, not dietary water, to excrete salt. So it wouldn't matter the concentration of the salt in the water you intake - your body would burn enough carbohydrates and protein to generate enough water to dilute it. I suppose in a starvation situation you'd be in extreme catabolism and just make everything worse.
    - maxerickson 9y ago
      Seawater is 35 grams of salt per liter, so even modest consumption of it involves considerably more salt than talked about in the study.
reitanqild 9y ago
I cannot remember the ratios or even if they mentioned it. I'd guess they started with a little saltwater in the rations and increased as they sailed.

pilsetnieks 9y ago

The negative impact is due to water loss via vomiting or diarrhea, and thus having a negative water balance. It's not like saltwater in itself kills you. In fact, you could drink the water of some less salty seas, e.g. the Baltic Sea.

int_19h 9y ago
The real bad impact is from disrupting the way your kidneys work. Basically, seawater has a higher concentration of salt than it is possible for your kidneys to remove via urine (due to the physics of that process). For one thing, your body will try to use its existing water supply to flush the extra salt, which means that you'll be urinating (= dehydrating) more than usual. Once that's all gone, and seawater is the sole source for water in your body, your body will no longer be able to produce urine to carry the usual toxins out. Eventually your kidneys will fail. Although in practice, you will feel like a wreck both physically and mentally long before then, and given that people in a situation where they can only drink seawater generally have other dangerous conditions to deal with, these debilitating effects can well kill you before that. This also explains why diluting seawater is potentially viable - so long as you keep the salt concentration below the level your kidneys can handle, you can keep them working normally.
- jaggederest 9y ago
  But the entire article is about the body using metabolic water, not dietary water, to excrete salt. So it wouldn't matter the concentration of the salt in the water you intake - your body would burn enough carbohydrates and protein to generate enough water to dilute it. I suppose in a starvation situation you'd be in extreme catabolism and just make everything worse.
  - maxerickson 9y ago
    Seawater is 35 grams of salt per liter, so even modest consumption of it involves considerably more salt than talked about in the study.

reitanqild 9y ago

I cannot remember the ratios or even if they mentioned it. I'd guess they started with a little saltwater in the rations and increased as they sailed.