Answering Common Microwave Concerns

Microwaves Q&A

Misconceptions about microwave ovens have been around since they debuted in the 1940s, but modern myths about the commonly-used appliance likely began with questionable research conducted in the 1980s and 1990s.

First, Hans Hertel, a Swiss food chemist, and seven other vegetarians spent two months consuming milk and vegetables that were prepared, among other ways, in a microwave, and announced that they experienced negative changes in their blood. However, no researchers have ever attempted to reproduce that experiment and it was never published in a scientific journal or peer-reviewed, which means the findings haven't been properly evaluated.

Later, an article by U.S. researcher William Kopp claimed that the Soviet Union had Cold War-era research that proved the machine's dangers. That research, conducted at a now-defunct institute, was also never published.1

There are other persistent rumors that plague the microwave oven. Some people still believe an unfounded claim that the Soviet Union banned the device in 1976. Others will cite a viral email from the mid-2000s that claims water boiled in a microwave killed a living plant, but that rumor has been recreated and debunked.2

Although these claims about microwaves can't be validated, people still have questions or misconceptions about microwave technology and the effect these machines might have on food. Read below as KaTom provides answers to some of the most common concerns people have about microwave ovens.

What are microwaves? How do microwave ovens work?

Microwaves are a form of electromagnetic radiation. They are reflected by metal, can pass through materials like glass, paper, and plastic, and are absorbed by food. Generated by an electron strip called a magnetron, they vibrate the water molecules in food at high speeds, which produces the heat that warms or cooks food.3

Do I need to worry about microwave radiation?

All household appliances emit electromagnetic fields that are not harmful if the machine is functioning properly, and household appliances are highly regulated to ensure their safety. Microwave ovens are specifically designed to only produce microwaves when the door is shut and the oven is on, and any microwave radiation leakage that occurs is well below recommended levels.4 Microwave ovens are also built with a Faraday cage, which contains electromagnetic energy inside the oven.5

Are microwave ovens safe?

Yes, as long as they are functioning well and used properly. Microwave ovens should always be kept clean and well-maintained to avoid poor performance or unexpected malfunctions. You should only use microwave-safe containers, which could be glass, ceramic, or plastic and should be labeled accordingly; metal pans and aluminum foil are not meant for microwave oven use, as they reflect microwaves and can damage the machine or improperly cook or heat food. 6 Microwave-safe containers can still become hot when used to heat foods and need to be handled carefully to avoid injury.

Can microwaves interfere with pacemakers?

It is unlikely that modern pacemakers will be affected by household appliances such as microwave ovens, televisions, and toasters.7 If you have any concerns about this possibility, you are advised to consult a physician.

Are microwave ovens only used for reheating?

Although reheating is a popular use for these appliances, they can also be used to thaw food before cooking. Microwaves are a quick method for steaming vegetables, although you should make sure to steam vegetables in a microwave-safe container with a lid to create a steam environment inside the container. They can also be used to safely cook poultry, meat, and fish, but you should use a food thermometer to make sure those items have been cooked to the temperatures necessary to destroy any harmful bacteria. 8

Does food prepared in a microwave lose its nutritional value?

All food loses some nutritional value as it is cooked, but the nutritional value of food cooked or reheated in a microwave, when prepared according to recommended procedures, is at least equal to that of food cooked or reheated using a conventional oven. 9 Some studies have even indicated that a microwave's short cooking time helps food retain more nutrients. 10

1. Microwave Myths: Fact vs Fiction David Schardt. Accessed October 2015.

2. Boiling Point Snopes. Accessed October 2015.

3. Microwave Oven Radiation: Cooking with Microwaves United States Food and Drug Administration. Accessed October 2015.

4. Electromagnetic Fields & Public Health: Microwave Ovens World Health Organization. Accessed October 2015.

5. Faraday cage Wikipedia. Accessed October 2015.

6. Use Your Microwave Safely United States Food and Drug Administration. Accessed October 2015.

7. Devices that may interfere with pacemakers American Heart Association. Accessed October 2015.

8. Microwave Ovens and Food Safety United States Department of Agriculture Food Safety and Inspection Service. Accessed October 2015.

9. Retention of Nutrients in Microwave-Cooked Foods National Center for Biotechnology Information. Accessed October 2015.

10. Microwave cooking and nutrition Harvard Medical School, The Family Health Guide. Accessed October 2015.