Dangerous Distilled Water?

Most recent answer: 01/09/2015

I would not classify mercola.com as scientific but I would like to see this bunkum(distilled water is dangerous) clearly and scientifically refuted.
- Nicole Anderson (age 66)
Berkeley Ca, USA

Some of those claims about distilled water being dangerous are bizarre. For example, that site claims "The most toxic commercial beverages that people consume (i.e. cola beverages and other soft drinks) are made from distilled water. Studies have consistently shown that heavy consumers of soft drinks (with or without sugar) spill huge amounts of calcium, magnesium and other trace minerals into the urine."  Cola has lots of phosphoric acid and all soda has intense carbonation, thousands of times higher than water picks up from CO2 in the air . That soda can create mineral deficiencies tells us nothing about the effects of distilled water. By the time that water gets into our gut, which is already intensely acid, the CO2 from the air makes essentially no difference. 

So the question becomes whether any of the metal ions (Ca++, Mg++, Li+, etc.) absent from distilled water but found in tap water, particularly hard tap water, improve health. Since most of the minerals we need (Ca, Mg,...) are obtained mainly from food, not water, we would not expect to see a dramatic effect. Nevertheless some studies find correlations between good cardiovascular health and some trace minerals in water supplies.  (See, e.g.,  ,
)  I don't think any clinical trials have demonstrated that these dissolved minerals are actually protective, but the correlations at least suggest the possibility.

Bottom line: The website you linked to about the dangers of distilled water is indeed baloney. The small amounts of dissolved minerals and CO2 in different water supplies are not a major perturbation on our intake of minerals, acids, and bases from various foods. Nevertheless, it's possible that drinking tapwater is marginally better for you thanks to some dissolved minerals. If, on the other hand, your water supply has Pb or Cd or pesticides, you'd be better off with distilled water.

Mike W.

(published on 01/09/2015)

Follow-Up #1: Is drinking distilled water safe?

Thank you very much for debunking the Mercola article! I would also like to see this other bunkum (demineralized/distilled water is dangerous) clearly and scientifically refuted. http://www.who.int/water_sanitation_health/dwq/nutrientschap12.pdf
- Monica Schott (age 41)
Santa Cruz, Bolivia

I can't debunk that article. It's based on actual scientific studies, of variable quality, of the effects of de-ionised water on health. The mechanisms discussed are at least plausible. There are no strange fantasies or irrelevant scare stories, unlike the Mercola article. So whether or not the conclusion of the article with respect to the importance of Mg++ in drinking water is correct (beyond our expertise) the article doesn't come close to meeting our rigorous standards for the "baloney" name.

Notice that even in the worst case, there would be no danger in occasionally drinking distilled water. It's not toxic. (DIstilled water subsequently piped through lead or cadmium contaminated pipes is another thing!)  The question is whether routine replacement of tap water with distilled water could lead to deficiencies in some mineral nutrients present in typical tap water. One suspects that would depend partly on what else is in the diet.

Mike W.

(published on 08/11/2015)