If microwave radiation is hazardous for human beings, then why isn't visible light?

Thanks everybody for the discussion, and especially Carl Pham for the extremely thorough and yet concise description. Very insightful.

I quite agree.
Carl Pham certainly did a lot to fight my ignorance with that excellent answer.

Thirded. Thanks,Carl.

Regards,
Shodan

In fact, part of why microwave ovens work so well is that, while they are absorbed by water molecules, they aren’t absorbed very well. As a result, microwaves will penetrate several centimeters, on average, into a water-heavy object before being absorbed. Which means that heat is deposited not just on the surface of objects, but within them, as well. Which leads to microwaves cooking food “from the inside”.