Table of ContentsView AllTable of ContentsRadiationCarcinogensBenefitsRisksSafety

Table of ContentsView All

View All

Table of Contents

Radiation

Carcinogens

Benefits

Risks

Safety

Microwaves may increase the risk of cancer, but so far there isn’t any strong evidence to support this. Most of what we know about the risks of microwave cooking is hypothetical and dependent on other factors, such as the plastics microwaved food is cooked in.

In theory, the exposure of certain foods and plastics to microwave radiation may create cancer-causing substances, calledcarcinogens. Microwaves might also deplete nutrients that protect against cancer.

This article explains what the current research says about the risk of cancer from microwaves and microwave cooking. It also describes the benefits of microwave cooking while offering tips on how to use microwaves safely.

Prapat Aowsakorn / iStock / Getty Images Plus

Asian mother and child using a microwave oven

Microwaves and Cancer

Microwaves are a type of low-frequency radiation classified as non-ionizing. Non-ionizing radiation is not linked tocancer. Other forms of non-ionizing radiation include:

The type of radiation associated with cancer is called ionizing radiation. This includes higher-frequency radiation such as:

Ionizing radiation causes electrons to be knocked off of atoms in molecules. This is what damages DNA in cells, causing some to turn cancerous.

Non-ionizing radiation from microwaves leaves atoms intact. It cannot make foods radioactive or change DNA.

How They Work and Potential Exposure

When food is placed in a microwave oven, the energy causes water molecules in the food to vibrate. These vibrations generate heat without altering the structure of the food.

When a microwave oven is working properly (and the door seal is intact), very little microwave energy leaks out. According to the U.S. Food and Drug Administration (FDA), the amount emitted is well below the level that is harmful to humans.

How Do Microwaves Impact Cancer Risk?

There is some evidence that microwave cooking can both increaseanddecrease the risk of cancer. Here is what the current evidence says:

Increased Risk

Though radiation from microwave ovens does not cause cancer, microwave cooking may pose an indirect risk due to its effects on foods or the containers the foods are cooked in. There is a possibility, albeit small, that microwaves can create carcinogens at higher power settings.

These include:

The risk is largely hypothetical and, to date, there is no strong evidence of such harm.Even so, for safety reasons, you should only use containers marked “microwave-safe” to cook or heat foods in the microwave.

What Is a Carcinogen?

Any method of heating can change the nutrient content of a food. When it comes to fighting cancer, the concern is largely related to how cooking affects substances in food known asantioxidants. Antioxidants neutralize molecules calledfree radicalsthat damage DNA in cells, causing them to mutate and possibly turn into cancer.

Decreased Risk

Can Grilling Meat Cause Cancer?

Benefits of Microwave Cooking

Because microwaves cook food faster than other methods and you don’t need to add water, microwaved food may contain more vitamins and minerals than foods cooked in other ways.

Vitamin C, for example, is a potent antioxidant found in citrus, tomatoes, potatoes, peppers, broccoli, strawberries, Brussels sprouts, and cantaloupe. Because vitamin C is water-soluble, boiling and steaming reduce its content while microwaving does not.

Does Garlic Reduce Your Risk of Cancer?

Other Risks of Microwave Cooking

Here are some of the other risks associated with microwave cooking that differ from other methods of cooking.

Radiation Injuries

While rare, a few cases of radiation burns have been documented due to the improper repair of microwave ovens. In such cases, excessive amounts of microwave radiation leaked through improperly placed or missing oven seals.

A microwave oven should never be used if the door seal is broken or if the light or turntable remains on after the door is open.

Uneven/Irregular Heating

One of the most common problems of microwave cooking is uneven or irregular heating. Microwaves penetrate food to a depth of around one inch or so. For this reason, foods may be hot on the outside and cold or frozen on the inside.

Another concern isfood poisoning. Some foods—especially raw meats or poultry—may not be cooked enough to kill harmful microorganisms in them.

When cooking raw meats in the microwave, it’s important to check the temperature with a food thermometer. Also, be sure to stir stews and soups one or more times in the cooking process to ensure they are heated through.

Explosion of Liquids

Normally, you can determine if a fluid is hot based on whether is it boiling. In the microwave, water can become superheated without ever boiling.

Removing superheated liquid from a microwave is a hazard because it can sometimes explode, causing a severe burn. The same might occur with potatoes or eggs baked in the microwave.

To avoid this, follow the recommended cooking times on the food product labels or use the preset cooking times on your microwave oven.

Metals in the Microwave

Placing metal in a microwave may damage the microwave more than the user, but is still a mistake. This not only includes pans, metal utensils, and aluminum foil but also metallic printing on cups or bowls, twist ties, and things like edible gold leaf.

Microwave Oven Safety

A few simple pointers can ensure your microwave is safe and effective in preparing the foods you eat.

Among the tips:

Summary

Microwaves utilize non-ionizing radiation that does not cause cancer and does not make food radioactive. It may change nutrient levels in foods, such as antioxidants that help fight cancer, but generally poses no harm to foods.

Some research suggests that microwaves may create carcinogens either directly or via the containers foods are cooked in, but the risk is largely theoretical.

11 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

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