|MadSci Network: Chemistry|
Yes, a microwave oven, as a heat source, affects some food nutrients. But, microwaves are just a heat source generated by a fancy electronic tube. True, those heat waves have special properties such as instant availability (you don't have to wait for the griddle to heat up) and microwaves can penetrate food better than some other heat sources. Microwaves are also selectively absorbed by some food components, e.g, fat and salt solutions. But beyond the simple heat effect, there's little solid evidence of adverse nutritional effects (selective food absorption by microwaves caused some errors in interpreting earlier data). On the beneficial side, a microwave oven, by not charring (or crisping) the food when reheating it, destroys fewer heat labile nutrients. One negative effect could be if the food is not throughly cooked (or reheated), any food borne disease could reduce nutrient absorption because of emesis or diarrhea (good words to look up for when you're speaking of gross things in polite company).
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