Why do people get dizzy and/or pass out when they hyperventilate?
Makes sense that that would happen if there’s too little oxygen in the blood, but too much? I would have thought oxygen-saturated blood would be a good thing…
When you hyperventilate, the main effect is to give off carbon dioxide. This has the effect of making your blood pH go up (become more alkalotic). The rising pH causes the blood proteins to give off their protons and thus the proteins develop more of a negative charge. That, in turn, causes calcium (which is positively charged) to bind to the proteins. The net effect is that there is less calcium freely available in the bloodstream.
The symptoms of hyperventilation are those of low blood calcium.