Give Now

A Moment of Science

Is Microwaving Safe for Food?

It's time to zap the myth that microwaving food somehow damages or irradiates it.

microwave light pours out in mesh pattern

Photo: Theen Moy (Flickr)

With any cooking method, some vitamins are lost at high temperatures. But because microwaves heat food up over a shorter period, less chemical changes occur.

It might not turn out crispy, but microwaved food is no less nutritious than any other kind of prepared food.

When Molecules Collide

Microwaves are low energy electromagnetic waves that have so little energy they can’t trigger chemical reactions in the molecules they encounter. And as long as there’s nothing in your microwave that can cause a spark, they also don’t leave behind any traces.

When you heat food in the microwave, what you’re actually doing is running an electrical current through the water molecules in the food. This causes the water molecules to rotate and collide, and these collisions generate friction that produces a lot of heat. The reason microwaves are so speedy is because food is made up mostly of water. In contrast, when you use an oven or a grill, you have to wait for the food to heat from the outside in.

The Heat Is On

Consequently, the only chemical and physical changes to your microwaved food are the result of the heating process. At high temperatures, sugars and proteins might interact, and vitamins might be destroyed. The thing to keep in mind is that these changes happen regardless of the method you use to heat food. What’s more, because microwaves heat up food so quickly, some of these changes might be less drastic than in foods that are heated up over a long time.

Read More:

“Is there any evidence that microwaving food alters its composition or has any detrimental effects on humans or animals?” (Scientific American)

Stay Connected

What is RSS? RSS makes it possible to subscribe to a website's updates instead of visiting it by delivering new posts to your RSS reader automatically. Choose to receive some or all of the updates from A Moment of Science:

Support for Indiana Public Media Comes From

About A Moment of Science

Search A Moment of Science