Very pure water dangerous to drink?

Factual Questions
1

There is an article in today’s Times that claims that very pure water would burn your insides if you drank it. Can this be true.

The article was about the making of the curling rink in Beijing. It said that the tap water had 375 ppm of dissolved solids and they had to filter most of them out to make curling ice. (As an aside you can’t filter solutes, can you?) It went on to say that the water was so pure it would burn your insides if you drank it.

I am afraid it is behind a paywall, but here is a link: https://www.nytimes.com/2022/02/16/sports/olympics/curling-ice.html

2

Total poppycock. The moment water enters your mouth is is no longer pure.

3

Yes, it is true: distilled water will damage your mucoses, also internally, through osmosis. It “sucks” the salts out of your cells.

4

Apparently it’s true
http://isciencemag.co.uk/features/fact-of-the-day-1/

https://blogs.scientificamerican.com/guest-blog/the-purest-of-them-all/

5

I’m not convinced that “leaching valuable minerals from your saliva” is that bad for you. The article says nothing about damage. By the time it gets into you (internally) it is not going to “suck the salt” out of your cells.

Of course, if you drink 5 gallons of it, all bets are off.

6

One or two pints on an empty stomach would be bad enough. A sip will dilute in your bodily fluids without a noticeable effect.

7

Is that how osmosis works? I thought it was about solvents moving through a semipermeable membrane from a weak to a strong solution. Not solutes.

8

Two pints may indeed cause a slight imbalance in your cell’s salt. But it’s not going to “burn your insides”.

9

I do not know. But super-pure water is used in some oilfield operations. My friends reported it was “nothing but wet,” lacking in any flavor.

I note distilled water does not require labelling as a dangerous chemical.

10

I’m just not swallowing that there is enough of a difference between “pure” water and tap water/well water that it will make a difference inside your digestive tract.

11

You are right, it is the water that enters the cells that makes them burst. But the effect is bad: water “wants” to achieve the same concentration on both sides of the membrane (the cell membrane in this case) so the cells fill up, inflate and may burst. If they don’t burst they still may be impaired in their chemical reactions and stop working properly.

12

Given the already huge difference in concentration of salts between cellular cytoplasm and ordinary tap water, why doesn’t that happen when you drink ordinary water?

13

WebMD says safe.

14

Natural selection has adapted us to what is found in nature: distilled water is not.
I only can get this in German, probably it is the same in the USA:

The bottle clearly states: not recomended for intake. And this is only demineralised according to VDE 0510, not even properly distilled.

15

So hemlock is safe, and coca cola is dangerous?

Sure, but that could be a caution against routinely drinking gallons of it.

16

The WHO released a report on the dangers of drinking demineralised water (this is a pdf):

https://www.who.int/water_sanitation_health/dwq/nutrientschap12.pdf

One of the main dangers seems to be that the water leaches minerals from pretty much anything it touches. So if you allow it to touch lead, the water will have lead in it…

Among eight outbreaks of chemical poisoning from drinking water reported in the USA in
1993-1994, there were three cases of lead poisoning in infants…<snip!>…For all three cases, lead had leached from brass fittings and lead-soldered seams in drinking water storage tanks. The three water systems used low mineral drinking water that had intensified the leaching process.

also:

severe acute damage, such as hyponatremic shock or delirium, may occur following intense physical efforts and ingestion of several litres of low mineral water

There are a few other dangers but I haven’t gone through the report in any real detail.

And it seems you have to drink a lot of it to cause any damage; and food or other drinks you consume will replace the mineral loss.

17

Non sequitur: that is not what I meant and I hope that was clear.

18

Which makes it approximately as dangerous as tap water.

19

But if you are drinking water with lead in it, you aren’t drinking “very pure water”.

20

Go down to your local grocery store, buy a gallon of distilled water, and drink it. Nothing will happen.