Watch out for dihydrogen monoxide… It has been found in 100% of all cancer cases but the government pumps it into our houses anyway…
https://en.wikipedia.org/wiki/Oxidative_stress
Not breathing may have more immediate side-effects though.
Though it is kind of wasted. Dihydrogen monoxide would be the chemical compound without any salts, minerals or other additives we normally get from water.
It would likely not be beneficial for you to drink it as opposed to water.