[kadoban]

Here's the MSDS for distilled water. http://erjair.com/MSDS/Distilled%20Water.PDF

This is about as calm as MSDSs get, note that it doesn't have any warnings about...anything really.

Besides which, I've drunk a small cup of it. No ill effects except it just tastes bad.

I think youtuber pranked you.

[ksaj]

Distilled water and pure H2O are not the same thing.

Pure Water Can Kill You http://isciencemag.co.uk/features/fact-of-the-day-1/

[kadoban]

That article is...suspect. Water poisoning is a thing, but it's a thing with normal water too. https://en.m.wikipedia.org/wiki/Water_intoxication

As with everything, the dosage is important and the article doesn't mention it being any different than normal water.