To Nuke or Not to Nuke? Should You Microwave Your Food?

Hand Opening MicrowaveAs a child of the ‘80s, I clearly remember the day my parents brought home our first microwave oven. We were lead to believe that, one day, everything from cupcakes to pot roast would breezily be cooked in the microwave while Mom enjoyed all her newfound free time.

What a difference a couple decades makes. Microwaves have since morphed from a space-age technology into a ho-hum appliance that reheats leftovers or zaps our lunch in under a minute. According to the USDA, over 90% of American homes have one, yet few kitchen appliances seem to evoke as strong and visceral a reaction. Why the controversy?

The secret behind your microwave is a device called a magnetron, which converts the electricity from your outlet into very short radio waves, which is a form of electromagnetic radiation. These waves cause the water molecules in food to vibrate, and it’s these vibrations that produce the heat that cooks the food. This use of “radiation” is the key sticking point in some circles when it comes to the impact on your health. As I see it, the question of “To nuke … or not to nuke?” really boils down to two different questions, which I’ve tackled here.

Question: Are microwaves “bad” for food?

Answer: It’s not worse than some other common cooking methods. While the Internet is teeming with articles that talk about how microwaves deactivate enzymes or destroy antioxidants, the truth is that many cooking methods do that, particularly boiling or pressure-cooking foods for long periods of time. Take broccoli, one of Dr. Oz’s favorite superfoods. A 2003 study examined this cruciferous cancer fighter and found that microwaving, boiling, and high pressure-cooking for long periods of time all slashed the flavonoid content, while steaming was best at keeping the nutrients intact.1 A 2009 study2 considered a wider group of veggies, subjecting 20 vegetables to a variety of cooking methods and then measuring antioxidant activity. Their conclusion? The vegetables actually varied widely in how much antioxidant activity they preserved – but a key finding was that shorter cooking time, using minimal water, is one of the best ways to retain nutrients. That study concluded that microwaving – because it shortens cooking time – actually preserved antioxidant capacity better than boiling and pressure-cooking in many cases. The authors quipped: “In short, water is not the cook’s best friend when it comes to preparing vegetables”.

Question: Are microwaves “bad” for you?

Answer: Microwaves are tightly regulated by the FDA in terms of emissions. The key is to be sure to use microwave-safe containers, such as glass and ceramics, and to avoid plastics, metal and aluminum. Microwaving your food in improper containers could possibly cause potentially harmful chemicals to leach from the container into your food, or in some cases (such as aluminum), cause sparks or fire.

If you are following a lifestyle where you are trying to limit all types of environmental radiation, then microwaves can be considered alongside laptops, cell phones, tablets, and other sources that have become common in American homes and lives (another dramatic change since the 1980s).

Ultimately, whether you choose to nuke your food is a personal choice. You may find its convenience a lifesaver, and a key appliance in helping you to eat a variety of healthy foods despite a hectic lifestyle. Or you may base your choice as much on philosophical or emotional reasons as science – like many other decisions we make about our food and our health every day.

If you do choose to use one, here are my six easy steps to guide you toward your highest level of health.

  1. Start with high-quality whole foods (fresh or frozen)
  2. Use microwave-safe containers (glass and ceramic).
  3. Prepare foods using minimal water and cooking times to preserve nutrients.
  4. Include several servings of fresh fruits and vegetables in your diet every day as well. (Buying produce in season and at local farmers markets when possible makes it both affordable and delicious).
  5. Stand several feet away while you are cooking your food.
  6. Be sure there are no cracks, and that the door and hinges all work properly.

Journal of the Science of Food and Agriculture, 2003: 80 (14) 1511-1516.
Jimenex-Monreal et al. Journal of Food Science: 74 (3) H97-H103.