The evidence is largely contradictory: http://en.wikipedia.org/wiki/DI_water#Health_effects_of_drin...

In any event, drinking deionized water doesn't appear to be instantly fatal. If the health impact is negative, then the effect size is pretty small.

Everyone needs to eat salt, and does. If there isn't any salt in your water, then you need slightly more salt in your food. But only very slightly more; drinking water is not very salty.

  It is unsafe to drink sea water due to high salt content.
  Therefore, drinking water with no salt content is also unsafe.

I do not understand that reasoning.

That reasoning is not present in the comment you're replying to (it says "like" where you've read "therefore")

I am unsure of how you could read the comment in any other way. How would you restate the argumentative form in the comment?

Just to be clear, I meant that water collected from pure air should have no salt in it at all, so drinking large amounts of it will be unsafe as it will draw those salts from your body (osmosis and diffusion), just like drinking large amounts of seawater might increase your blood pressure, but more importantly, it's very hard for your body to get it out of your system, your urine produced by your kidneys is not saltier than saltwater, so you need more water than you can drink (with seawater) to get it out again.

So my original question still stands, is it unsafe to drink large amounts of water collected from pure air and do they have to take care of that in any way? Or will simply eating salty food fix it? I still have not found an answer in the article.

EDIT: From further below in the thread:

http://en.wikipedia.org/wiki/Hyponatraemia

and its counterpart:

http://en.wikipedia.org/wiki/Hypernatraemia

It's dangerous if you're dehydrated and drink a lot of soft water (that's the term for water with low/no mineral content) at once, otherwise it's okay as long as most minerals come from the diet.

Tap water in most places has a GH/KH of 0 (to avoid clogging pipes with carbonates) and nobody dies from it.

Specifically, if your body is low on electrolytes it will hold water until it gets them and that holding of excess water causes problems. However, almost any amount of food is sufficient to prevent that.

However, in this case I tend to doubt the water will be all that pure due to dust; I'd guess it will actually have a decent mineral content. Commercial water purifiers often produce mineral-free water and the only issue I have heard of in connection with this (at least as long as you are eating any food) is that most people find that the resulting water tastes bad. Adding minerals back is not difficult at all.

Edit: Sounds like it is a little more complicated than that; the WHO paper that the Wikipedia article that sbierwagen cites is a good read with 16 pages on this topic. One thing they mention as a potential issue is that cooking food in low mineral content water can leach minerals from the food. If the food is then consumed but the water isn't, that would lower mineral intake (discarding water used in the first cooking of some beans is necessary because it removes toxins from the beans but these beans can be a good nutrient source, so this could still potentially be an issue where water is scarce). The Wikipedia article could be skipped, though, so here is a direct link to the paper: http://www.who.int/water_sanitation_health/dwq/nutrientschap...

I read it as a question, because of the question mark, not a statement/argument.

If one extreme (high salt) is bad, is the other extreme (no salt) also bad?

I suppose it could be an argument but the way I read it was that they were unsure and would like to know more.

Drinking water is supposed to be good health if the salt content is between 30 to 50 parts per million. If we speak about details the salt content present in water is supposed to be source of some minerals which you might not be able to get from food. It can also be supplemented with vitamin tablets but that would make distilled water not ideal drinking water.

Ultra pure water will leach salts from the body. This is dangerous.

At least, that's what people suggest, I don't know if it's true.

It's called hyponatraemia; check it out at wikipedia http://en.wikipedia.org/wiki/Hyponatraemia

A downvote for a pure statement of fact?

It's not dangerous at all if there is sufficient salt balance in the diet.

Heck, I drink DI water on a daily basis and have a low sodium diet replaced by potassium salt where possible.

have faith in your GI system...it usually figures out what to absorb.

The issue with deionized water isn't what your GI system will or will not absorb. The issue is that the water may absorb minerals and nutrients from you.

I have to imagine that this is easily combated if it proves to be a significant factor. Worse case scenario, now that you have water that doesn't make you violently ill, you have more energy to farm/eat nutrient rich foods?

If you are just drinking water and not eating, then this could be a problem, but then you have other problems anyway.

If we are talking about installing these to rural parts of Africa, having to eat more may be a valid consern.

We are talking about trace quantities of salts though. You could get around any measurable problem by passing the water through a large box full of pebbles. Also, water is for agriculture as well as drinking, so this should increase the stability of food supply anyway.