Are Microwaves Actually Bad For You?

By Emma Stessman

When I was seven, my mom told me that standing directly in front of the microwave could cause cancer. She wasn’t one to sugarcoat things, and I wasn’t one to question her authority. From then on, every time I hit the start button, I would sprint into the next room and hide until I heard the beep signaling my food was ready.

Of course, I was heating up Hot Pockets and corn dogs at the time, so the microwave was likely the least of my worries. But even now, years later, whenever I heat up a bowl of frozen broccoli or nuke my favorite Indian entree from TJ’s, I can’t help but feel a little wary.

While the appliance is a super handy cooking tool—making quick veggie steams and meal prep re-heats so much simpler—its reputation has been tainted by rumors of radiation and nutrient degradation. Thankfully, the dangers of microwaves are little more than old wives’ tales. “There is really nothing to worry about with microwaves,” says Darrell Cockburn, Ph.D., an assistant professor of food science at Pennsylvania State University.

Need some evidence? We’re using science to debunk the most common microwave myths, below.

Do Microwaves Destroy Nutrients?

The truth is that any cooking method—microwaving, grilling, or sauteing—can break down certain nutrients in food. That being said, cooking time, temperature, and the amount of liquid used tend to have the most significant effects on nutrient loss. Since microwaving cooks food quickly and requires low amounts of liquid (unlike, say, boiling), it’s actually one of the better cooking methods for nutrient retention.

In fact, in a 2009 study, researchers tested how various cooking methods affected the antioxidant content of 20 different vegetables. They found that microwaving, along with baking and griddling, led to the fewest antioxidant losses (while methods like boiling and pressure cooking had a greater diminishing effect).

The key is to avoid cooking for too long. “As with any form of cooking the heat introduced can destroy valuable nutrients over time, so care should be taken to not overcook foods,” Dr. Cockburn says.

The bottom line: You may have to worry about losing culinary cred among chef and foodie friends if you start microwaving everything, but you don’t have to worry about losing nutrients.

Can Microwaves Cause Cancer?

Microwaves (the physical appliances) work by using microwaves (specific frequencies of electromagnetic radiation waves) to cook food from the inside out. “The microwaves mostly interact with water in the foods, heating it up, and in turn heating the surrounding materials,” Dr. Cockburn says.

Of course, in our minds, the word radiation comes with some seriously negative connotations. And while there is some radiation on the inside, that’s where it stays. “Microwaves are designed to keep virtually all of the radiation inside,” Dr. Cockburn says. “There are regulations that force manufacturers to ensure that only minute quantities are able to escape the microwave.” And the minute amounts that do end up escaping don’t make it very far. “Standing even a foot or two away reduces the very small amount of microwaves to almost nothing,” he says. For those thinking about their food sitting in the circulating radiation, not to worry, the chemical structure of the food doesn’t change, so your broccoli won’t be radioactive.

Things do get dicey when it comes to containers. If you microwave your food in plastic containers, harmful substances like BPA can leak onto the food. Stick to bowls and plates made from microwave-safe materials, such as glass or ceramics. (I mean, you should probably break up with your plastic anyway.)

So while my hiding-from-the-microwave sprints may have been for naught, I’d like to think they helped me in other ways—like giving me a leg up during cardio in HIIT classes.

(Photos: Shutterstock)