That is simply because they all use the
same method — the scientific
method — which is the
same method they have used to discover virtually everything we use and know today, i.e. computers, telephones, GPS,
microwaves, etc..
As for the
microwaves damaging your food, it does so no more than any other cooking
method (all heating of food will damage proteins and enzymes, but your stomach does the
same thing!