"Some animals create fire from their mouths."

Wat?

"Microwaves are not really natural..."

Perhaps, not being a physicist, you may be unaware of the map of the universe based on the cosmic background radiation - basically microwaves - that best reveals the evolution of the matter after the initial 'Big Bang'. You also, not being a biologist, may be unaware that dragons aren't actually - and never were - living things, but fictional creatures.

Microwaves are the same thing as light, just at a different frequency, and are a constant in the natural environment. Also, I never said fire and microwaves are the same, so pointing out they are different isn't relevant to what I did say. What I did say is that cooking is novel in the natural world, and both fire and microwaves as methods of cooking are both 'unnatural' in the sense that no other creature has ever employed them.

And the very next thing you ask is why I'm denying reality.

This is the very first sentence of my comment on the OP:

"I have no doubt that microwave ovens contribute to disease, perhaps too much. There is too little research into this, and I appreciate you bringing it up."

Try to keep that in mind when insinuating I advocate for cancer or implying I recommend drinking mercury.