Is it dangerous to drink river water?

How dangerous is drinking distilled water?

"Never drink distilled water!" Almost everyone has been familiar with this warning from childhood. The fear that body cells could burst and gastric bleeding even lead to death leads many people to avoid ion-free liquids as a thirst quencher, even in adulthood.

"There is no truth in this myth," says physiologist and nutritionist Cem Ekmekcioglu. "Distilled water, drunk in the usual quantities, is completely harmless and harmless with normal kidney function."

Basically: Drinking is life-sustaining and is responsible for maintaining the electrolyte and water balance in the human organism. Permanent isoosmolarity and a constancy of the fluid volume are the physiological goals of this regulating activity. Isoosmolarity exists when the same osmotic pressure prevails inside and outside the body cells, i.e. when there is a largely balanced distribution of electrolytes both inside and outside. In order to compensate for any differences in concentration, water flows into or out of the cell, depending on the fluid space in which the osmolarity is to be compensated.

Remineralization in the stomach

It is now well known that distilled water is completely free of electrolytes, trace elements, minerals and pollutants. This hypo- or "zero" osmolarity has presumably led to the speculation that drunk distilled water flows into the cells of the gastrointestinal tract in order to adapt the relatively higher osmolarity within the cells to the lower one outside the cells. The alleged consequence of this: cells cannot cope with the massive influx of water and burst. This can cause fatal bleeding in the stomach.

There is a very simple reason why this does not happen: "Distilled water is largely remineralized in the stomach and upper small intestine," says Ekmekcioglu, who works at the Physiological Institute of the Medical University of Vienna. In general, distilled water differs only slightly from tap water in terms of osmolarity. And both liquids are completely harmless when consumed in normal drinking quantities.

A lot in a short time

However, both distilled and simple tap water can cause health problems for people. However, only if a lot of fluids are drunk in a very short time. In the worst case, such water poisoning can even be fatal. "The main issue here is how much the blood is thinned," said Ekmekcioglu.

The excess water reaches the surrounding tissue via the blood vessels, where the organism in turn tries to create an iso-osmolar environment by transporting fluid into the body's cells, which then swell. In the case of water poisoning, it is above all the swelling of the brain cells that acutely threatens the life of those affected.

Theoretically, the same life-threatening consequences would also arise if distilled or tap water were infused directly into the bloodstream.

Aromatic fountain of youth

But distilled water is not feared everywhere as a luxury food. In some countries in Southeast Asia, the ion-free water is industrially bottled and sold to consumers as "premium" water. And in Europe, too, some people swear by the flavoring effects of tea or coffee preparation. Others believe in a detoxifying effect or even call distilled water a fountain of youth.

"In terms of pollutants, drinking distilled water is definitely an advantage", Ekmekcioglu is convinced, but adds that mineral water, for example, as a supplier of calcium, magnesium, but also certain trace elements, is far superior to distilled water in terms of health. (Regina Philipp,, June 14, 2012)