How does distilled water cause loss of minerals?
Our best understanding is that the pure water causes an influx of sodium ions into the gut. Whenever there is excess sodium in the gut, it causes a cascade of responses in order to maintain balance in electrolytes, as shown in a current anatomy and physiology textbook. The excess sodium in the gut increases blood sodium levels and pulls water from intracellular fluid into the bloodstream. This increased volume then raises levels of atrial natriuretic peptide, decreases formation of angiotensin II, and decreases aldosterone secretions by the adrenal cortex. These three responses cause a greater loss of sodium and chloride ions and water through the kidneys into the urine in order to reduce blood volume. This cascade of homeostatic control was designed to take into account different levels of electrolyte intake, and works well, especially for elevated intakes. However, when no sodium was initially taken in, yet more was excreted this creates a problem that has to be re-corrected, which t
