Many people wrongly assume that distilled water is ideal drinking water. In reality distilled water is the strongest poison. It is possible for man to drink water that exceeds maximum permissible concentration of copper, iron, even mercury for some length of time (with an obvious effect on his health but man will die if he drinks distilled water for more than a week. Why? Because water deprived of all dissolved substances and being a good solvent starts to wash them away from the organism.