{"id":19318,"date":"2025-04-16T10:00:00","date_gmt":"2025-04-16T17:00:00","guid":{"rendered":"https:\/\/foodrevolution.org\/?p=19318"},"modified":"2026-09-15T07:57:35","modified_gmt":"2026-09-15T14:57:35","slug":"are-microwave-ovens-safe","status":"publish","type":"post","link":"https:\/\/foodrevolution.org\/blog\/are-microwave-ovens-safe\/","title":{"rendered":"Are Microwave Ovens Safe To Use?"},"content":{"rendered":"

Comedian Steven Wright said, \u201cI just bought a microwave fireplace. You can spend an evening in front of it in only eight minutes.\u201d<\/p>\n

Like Wright\u2019s imaginary fireplace, microwave ovens can also save us time. In this case, they can speed up defrosting and cooking our meals. In our busy world, microwaves have become such a default cooking appliance that, for many of us, it\u2019s hard to imagine living without one.<\/p>\n

But despite their popularity, questions linger about their safety. Concerns about microwave radiation, loss of nutrients in food, and proper usage continue to spark debate.<\/p>\n

In this article, we\u2019ll examine the pros and cons of microwave ovens, share tips on using them safely, and discuss which foods are best to cook in them.<\/p>\n

What Are Microwaves and How Do They Work?<\/h2>\n
\"Still
istock.com\/1shot Production<\/figcaption><\/figure>\n

Microwave ovens have been widely available to consumers since 1967<\/a>, but the first one was invented in 1946. An engineer named Percy Spencer discovered the capability of microwaves to cook food when he accidentally melted a candy bar in his pocket while standing next to a magnetron (a device that produced the radar waves used to detect aircraft during World War II).<\/p>\n

Instead of bemoaning his dry cleaning bill, Spencer got excited and held a bag of unpopped popcorn beside the magnetron. This time, instead of stained trousers, he got delicious hot popcorn. This was a prescient choice: popcorn is still one of the most popular microwaved foods<\/a>.<\/strong><\/p>\n

Microwave ovens use microwaves<\/a>, electromagnetic waves that are longer than infrared radiation but shorter than radio waves. A magnetron device converts electrical energy into microwaves and sends them into the cooking space through a special channel or waveguide.<\/p>\n

Contrary to popular belief, microwaved foods don’t cook from the inside out<\/strong>. Instead, microwaves excite water molecules<\/a>, which wriggle back and forth to produce friction and heat. Since water is unevenly distributed in food, most microwave appliances include a rotating glass turntable to cook food more evenly and prevent cold spots<\/a> (although this is often an imperfect process, as anyone who\u2019s bitten into a frozen chunk in a steaming microwaved calzone can attest).<\/p>\n

Are Microwave Ovens Safe?<\/h2>\n

Microwave ovens use radiation to heat food \u2014 a fact memorialized in the slang for using the appliance: \u201cnuking\u201d food.<\/strong> However, the real health concerns with microwaves have more to do with the foods and containers we put in them than with the nature of the heating process. Let’s examine the facts.<\/p>\n

The Association Between Microwaves and Unhealthy Foods<\/h3>\n
\"Frozen
istock.com\/Andrew Gardner<\/figcaption><\/figure>\n

One of the biggest issues with microwave ovens is not the appliances themselves but the foods that are often cooked in them. In our busy, on-the-go society, people often use microwaves to cook or heat up ultra-processed frozen meals and food-like products that are not doing human health any favors.<\/strong><\/p>\n

Since the 1950s, the food industry has innovated tens of thousands of products designed to cook in microwave ovens. But many of these foods contain excess sodium, GMOs, natural flavorings, preservatives, and other unhealthy ingredients.<\/p>\n

There\u2019s a world of difference between microwaving an industrially produced frozen TV dinner and cooking some frozen vegetables \u2014 especially when said vegetables are cooked in microwave-safe dishware. While the former can harm your health in the long term, the latter is a fine way to warm or cook food in a hurry.<\/p>\n

Heating Plastic in the Microwave<\/h3>\n

Many TV dinners instruct you to cook them with some of the plastic packaging still intact. But when plastic is heated, toxic chemicals like BPA and phthalates can leach out<\/a>, contaminating your food with endocrine disruptors.<\/strong><\/p>\n

Even so-called microwave-safe plastic containers may not be what they seem. The Milwaukee Journal Sentinel<\/i> put 10 \u201cmicrowave-safe\u201d containers<\/a> through a microwave oven and tested them in a lab. The containers included plastic types 1, 2, 5, and 7. The results showed bisphenol A, or BPA, leached from all of them when heated in the microwave. And the amounts detected were at levels that can cause neurological and developmental damage in laboratory animals.<\/p>\n

Phthalates found in plastics may also disproportionately affect children\u2019s health, including increasing the risk of metabolic disorders<\/a>, asthma, and ADHD<\/a>.<\/strong><\/p>\n

Frederick vom Saal, a University of Missouri researcher who guided the newspaper’s testing, commented: “There is no such thing as safe microwaveable plastic.\u201d<\/i><\/p>\n

Microwave Radiation<\/h3>\n
\"Device
istock.com\/Volodymyr Kazhanov<\/figcaption><\/figure>\n

The World Health Organization notes that one of the biggest myths<\/a> about microwave ovens is that foods cooked in them become radioactive. After all, \u201cnuking\u201d does have some pretty terrifying connotations.<\/p>\n

But while microwave ovens emit a type of microwave radiation<\/a>, it\u2019s non-ionizing, unlike nuclear and x-ray radiation, both of which are ionizing.<\/strong> What\u2019s the difference? Non-ionizing radiation means electrons are not knocked out of affected atoms, whereas ionizing radiation can alter atoms, molecules, and cells.<\/p>\n

According to the FDA<\/a>, which has been regulating microwave ovens since 1971, radiation-related microwave injuries, such as burns, are very rare. Cases are typically the result of improperly serviced appliances that leak, causing people to become overexposed to microwave radiation. In comparison, getting burned by a conventional oven \u2014 such as being hit by a blast of hot air when the door is open or exposing yourself to harsh elements \u2014 is a more common and immediate risk.<\/p>\n

FDA regulations require that microwave ovens be sealed to prevent high-level radiation leaks. Their website notes that there is little concern about radiation leakage unless the microwave’s door seal, latch, or hinges are damaged. If you can\u2019t fully close the door to your microwave, the FDA recommends no longer using it.<\/strong><\/p>\n

Cancer-Causing Compounds?<\/h3>\n

Another concern about microwaving food came from a 2015 study<\/a> published in the Journal of Food Processing and Preservation<\/i>, which raised concerns about cooking meat in a microwave. The study found microwave cooking produced more cancer-causing heterocyclic aromatic amines (HCAs) than pan-frying or baking.<\/strong> Microwaving also produced more HCAs than barbecuing, the cooking method most closely linked to HCA formation.<\/p>\n

While the study didn\u2019t definitively say microwaves cause cancer, if you consume animal products, you may want to think twice about heating them in the microwave.<\/span><\/p>\n

Microwaving can also cause acrylamide formation<\/a>. Acrylamide forms in starchy foods when cooked at high temperatures, typically producing browned, crispy surfaces\u2014such as those seen in French fries or potato chips. However, browning is minimal when microwaving, so only trace amounts of acrylamide might form.<\/p>\n

It\u2019s worth noting that acrylamide formation in microwaves is a concern primarily with the prolonged cooking of starchy foods, like potatoes, rather than the brief reheating of meals.<\/strong> For most everyday microwave use, such as warming leftovers, acrylamide formation is not a significant issue.<\/p>\n

Although acrylamide is classified as a probable carcinogen, debate exists on whether the amounts typically found in food are enough to cause a problem.<\/p>\n

For more on acrylamide, check out our in-depth article: Is Acrylamide Dangerous & How Can You Avoid it in Your Food?<\/a><\/p>\n

Undercooked Food<\/h3>\n
\"Women's
istock.com\/Olga Ihnatsyeva<\/figcaption><\/figure>\n

Despite their rotating turntables, microwaves don’t always cook foods evenly. (While pressing an eye against the door glass to survey the revolving plate may be hypnotic, it doesn\u2019t give you much actionable information about whether your burrito is fully heated.)<\/p>\n

Solid foods take longer to reach optimal temperatures in a microwave than fluid or semi-fluid foods because they contain less water.<\/strong> You can compensate by adding extra liquid or pausing the microwave and stirring the dish before resuming cooking.<\/p>\n

While undercooked food isn\u2019t ideal in any scenario, it\u2019s downright dangerous for meats, fish, and other high-risk, animal-derived products that must be heated to 145\u2013165\u00b0F<\/span><\/a>\u00a0to kill pathogens. When cooking these kinds of foods in the microwave, it\u2019s recommended that you use a food thermometer to check internal temperatures.<\/strong><\/p>\n

Possible Nutrition Loss<\/h3>\n

There are also concerns that microwaving food may reduce<\/a> its nutritional quality. However, these concerns may not be as serious as they initially sound.<\/p>\n

For example, a study published<\/a> in the International Journal of Food Sciences and Nutrition<\/i> found that protein from microwave-cooked legumes was 5% less digestible than protein from legumes cooked in a pressure cooker. This difference likely reflects the enhanced breakdown of cell walls achieved through pressure cooking rather than an inherent shortcoming of microwave heating.<\/p>\n

A review in the Journal of Nutrition<\/i> also found that a 60-second microwave heating time was long enough to deactivate<\/a> the cancer-fighting compound alliinase in garlic. This is a good reason to eat garlic raw. But again, it\u2019s not inherently a problem with microwave cooking. Any cooking method \u2014 including steaming and saut\u00e9ing \u2014 that exposes garlic to sufficiently elevated temperatures may also deactivate alliinase.<\/strong><\/p>\n

Critics may also note that because water is often added during microwave cooking, water-soluble vitamins like B vitamins and vitamin C can leach into the cooking water. However, this isn\u2019t unique to microwaving \u2014 similar losses can occur with other cooking methods that use water. To minimize nutrient loss, steam your food in a closed container with a lid, and if you do use any cooking water, incorporate it into soups or as a base for cooking grains to recapture those vitamins.<\/p>\n

To summarize, microwaves don’t cause nutrition loss any more than other forms of cooking.<\/p>\n

4 Potential Benefits of Using Microwaves<\/h2>\n
\"Two-tier
iStock.com\/grzymkiewicz<\/figcaption><\/figure>\n

Microwave cooking isn\u2019t all downsides and harm mitigation. There are also some benefits to consider.<\/p>\n

1. The Convenience of Microwaves<\/h3>\n

Microwave ovens are just about the fastest and easiest way to prepare (or at least heat) many foods.<\/strong> Their speed and ease of use can be a game-changer for people with hectic schedules, enabling them to quickly cook meals or reheat leftovers without much effort. This convenience often removes a common barrier to eating healthier foods, such as vegetables, which might otherwise seem too time-consuming to prepare.<\/p>\n

In most cases, the best way to cook vegetables is the one that gets you to eat them. For some people, based on convenience, that may be in a microwave oven.<\/p>\n

2. They’re Easy to Clean<\/h3>\n
\"Girl
istock.com\/MediaProduction<\/figcaption><\/figure>\n

Microwave ovens are also easier to clean than most conventional ovens.<\/strong> You can put the glass turntable in the dishwasher or wash it by hand. If food splatters inside the microwave, inexpensive and non-toxic cleaning products like water, dish soap, baking soda, and vinegar can remove the residue.<\/p>\n

Here\u2019s a video showing a cool way to clean your microwave\u2019s interior using a bowl of water with added vinegar and lemon quarters:<\/p>\n\n

\n
\n
\n