Why were they dehydrated?


Why were they dehydrated?
There was plenty of snow everywhere.
What stop them from chewing the snow and thus hydrating themselves?

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According to the article I have linked to below

“Cells and organs in the body need water to be in a liquid state, so the body must work to heat and melt the snow once it is eaten. Because the organs must work harder to heat the ice and melt it, you will become further dehydrated rather than hydrated.”

https://www.sunnysports.com/blog/outdoor-myths-eating-snow-dehydration/

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THAT'S REALLY INTERESTING! THANK YOU!

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While eating too much snow in a short period of time may cause hypothermia, it will not dehydrate you. That's a myth that seems to be perpetuated with an almost religious fervor.

The calories that the body burns to generate the metabolic heat required to melt the snow once it is consumed do not require more water to process than what you consume from frozen water.

Like many such myths, there is either a misunderstanding from an original source or there is a claim that is cited by blogs and news articles, which are then cited by other blogs and news articles, until it becomes accepted as fact. However, there is no actual scientific basis for it.

Also, like many myths, there are just as many blogs and articles that refute or debunk it as there are to claim it.

Here's one sample of an attempt at scientific explanation extracted from a blog post.

The calories to melt even frozen water are pretty small, and the water gained is certainly greater than that used to aid the use of those calories.

So 1 calorie = 1 degree Celsius (roughly with minor variation). Okay easy. Except it takes 80 times that to melt it initially.

1 liter of water frozen to ice at 0 °C
1 liter water = 1 kg water, (1000g * 80) 80,000 calories to melt the ice and then 37500 for the next 37.5° (to achieve 37.5 °C, temperature of the human body)

117500 little c calories

That's 117.5 dietary calories, because a dietary calorie is actually a kilocalorie.

How much water does it take to process 117.5 dietary calories? No where near a liter or we'd all be dead the next time we ate a Christmas supper.

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Thanks for the info, aavfreak.

I googled why they were dehydrated and came across the explanation I quoted. I realise now that that explanation is probably wrong.

However they definitely were thirsty/dehydrated while on the mountain. Some of the survivors have stated the thirst was worse than the hunger.

EDITED TO ADD - I did find this quote by Nando Parrado.

“ What surprised Parrado most was the unbearable thirst. “You need water permanently. You dehydrate five times faster at that altitude than at sea level. And there’s no water, so you have to eat snow.” It was so cold it burned their throats and cracked their lips.”

So maybe they were dehydrated for those reasons (?)

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Yes, he's correct about altitude and dry air in general. It will suck the moisture right out of you.

Based on what you quote here, it seems the root of the issue is that they couldn't consume enough snow to compensate for the natural dehydration they were suffering, not necessarily that the snow was causing the dehydration.

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