Does using a microwave (to cook food) leach food of its nutrients?

This is a question that has been batted around by my coworkers on and off for years. Some customers say yes. Then again, other customers say that we're supposed to eat to balance our pH, or according to our blood type, that eggs are evil and we shouldn't sell them, that High Fructose Corn Syrup can kill you (not "it's bad for you," no, it can kill you), that the laser scanners at our registers zap the "energy" out of food ... so we don't know what to think.

Some of you out there, however, might posess the kind of educational background to actually give an informed answer.