A microwave is a terribly useful device that seems to almost magically make food heat up. So how exactly do they work?
A microwave oven uses what’s called a magnetron to produce microwaves which pass through food, hitting water molecules and causing them to vibrate. This vibration produces heat, which spreads, cooking your food. As microwaves are a wave, they only hit the water molecules if they are in the wave’s path, which is why microwave ovens rotate you food, to more evenly heat.
Microwaves are a form of electromagnetic radiation, the same thing as light, but operating at a higher frequency; around 1 to 100 Gigahertz. Microwaves radiation is not the same thing as nuclear radiation, and it cannot cause radiation poisoning or cancer. However, prolonged, unshielded exposure to microwaves can cause burns, but this is only likely to happen if your microwave is tampered with to allow operation with the door open.
Microwaves range in size from 1 millimetre to 100 centimetres, preventing them from passing through the mesh you can see in your microwave’s door. This means that a microwave with an undamaged, closed door is completely safe and cannot cause any harm. Further, microwaves do not make food in any way toxic or dangerous, asides from making it hot. There is some limited evidence to suggest that microwaves may slightly affect the nutritional content of food, but not in any way which is hazardous to your health. As long as your microwave is undamaged and not tampered with, it is an easy, safe way to quickly heat your meals.