The invention of the microwave has definitely made cooking more efficient and saves a great deal of time in the kitchen. But many people wonder whether or not microwaves are dangerous and safe for the food that you eat. Determining how safe microwaves are and getting answers to these questions first begins by understanding how microwaves work. Here is a brief overview of the microwave oven and the answers to some of the questions you might have about using yours, or which one to buy if you decide to replace your current microwave at some point in the future.

Microwaves are designed to make heating convenient.

Microwaves are designed to make heating convenient.

What is a Microwave Oven?

So, what is a microwave oven and how does it work? A microwave is a shielded container that shoots microwaves at the food inside. It can cook food very quickly and it is used in almost every kitchen in the United States and in many countries. Microwave ovens are cheap, convenient and widely available and are used to cook all kinds of foods. Although the microwave can cook food, it is almost always used to reheat food that has been refrigerated, either homemade leftovers or something from the freezer aisle of your grocery store specifically made for microwaves.

History of the Microwave

image-2The person that discovered that microwaves were able to cook food quickly was an engineer working at the time for the company Raytheon in Howland, Maine. Percy LeBaron Spencer was working with microwaves in connection with the active radar set he was experimenting on, and noticed that the chocolate bar that had in his pocket had melted. He began to conduct experiments with microwaves and found that they raised the temperature of all kinds of foods, cooking them in minutes. The first food that was cooked using microwave (not counting the original candy bar) was popcorn, followed by an egg, which ended up exploding due to the buildup of heat inside the shell.

Raytheon, the company Spencer worked for, filed a patent application for the microwave. The first units used outside of the labs were enormous compared to the microwaves of today. The first one was placed in a restaurant in Boston for a trial run. A hot dog vending machine was installed with a microwave shortly afterward at Grand Central Station in New York City, which allowed people to cook their hot dogs in seconds. The only reason that the microwave was discovered in the first place was because scientists during the Second World War invented the magnetron, which was a device that emitted microwaves.

How Does a Microwave Work?


So, how does the microwave work, anyway? Are they dangerous or unhealthy? The microwave is basically a metal box that shoots microwaves into the middle of the box which are then bounced around the space and cook food through dielectric heating. What this means is that instead of cooking food by convection – which is heating up the container (oven) and allowing heat transfer from the outside of the food to the middle. That’s why if you put something in the oven on too high of a temperature, the outside might become burned while the inside is still uncooked.

But microwave ovens work differently. The magnetron releases electromagnetic radiation and it is absorbed by the molecules of the food, which causes atomic motion – or the spinning of polar molecules to create a thermal reaction. This is what makes food cook so fast. An interesting thing about these microwaves is that while they are absorbed by sugars, fats and water, they are not absorbed by most plastics or by glass or ceramics. That’s why you can put something in the microwaves and heat it up to boiling and still remove the container without burning yourself. The microwaves are reflected by metal, which is why you can’t use it in the microwave and why the walls are made from a metal that is specifically for reflecting them around the oven.

Are Microwaves Safe for Humans and Pets?

To determine whether or not microwaves are harmful to humans or pets is difficult, especially if you are using the web to get your information because there are many websites that claim that microwaves are harmful to our health. The first thing that makes people cautious of microwaves is the concern that they are leaking radiation. Unfortunately, this is true. Microwaves do leak radiation but so do most of your other electronics that you have in the house – phones, tablets, laptops and more. None of the radiation levels put out by any of those devices is enough to cause any damage to humans or pets.


That’s because the Food & Drug Administration (FDA) has very strict guidelines governing how much radiation can leak from a microwave oven (or other electronic devices) throughout its lifetime. The amount that a microwave leaks is much lower than the amount or radiation that would cause human beings harm. Also, as soon as you open your microwave door, the waves stop being emitted. Neither the microwave itself nor the food that you are cooking can absorb this radiation. What this means is that microwaves are extremely safe, and if you want to avoid the potential radiation even further, just go wait somewhere else for the food to be done. The microwaves do not extend very far past the oven itself.

One thing to bear in mind, however, is that because we are just now starting to incorporate electronics into our lives, nearly every waking hour, the cumulative effect of these devices are unknown and needs to be studied. When the FDA made the rules on how much radiation could be leaked, they didn’t take into account that in a few decades we would be carrying devices that leak those tiny amounts of radiation nearly 24/7. So are microwaves danger or harmful? No, but all of the microwave radiation that leaks out of our devices might have some long-term effect on the human body but right now that is pure speculation.

What Other Hazards do Microwave Ovens Pose?

To be safe, use oven mitts when taking out food from the microwave.

To be safe, use oven mitts when taking out food from the microwave.

So, what other factors might make microwave ovens harmful? There are a few additional factors to keep in mind if you own a microwave oven. The high temperature is the main problem that you need to worry about. For example, you might heat something in the microwave and then handle it or taste it and it will scald you. The same thing goes for liquids in the microwave which may not actually boil until you put something in them which could cause the water to splatter outwards and burn your skin. However, these occurrences are rare and can be avoiding by following the instructions carefully.

You also have the danger of metal objects being placed in the microwave oven, which will cause an electrical current and could be dangerous, and might seriously damage the microwave. Most types of metal will trigger this reaction and almost no metals are able to be used inside of a microwave. Pointed objects, such as the tines of a fork, are particularly problematic. Another thing that might make microwaves dangerous is the exposure to the radiation itself. This is obviously a very minor concern if you use the microwave properly, but if the microwave has been damaged and split open, there is the potential for electromagnetic radiation to leak out if the device is turned on. Also, broken magnetrons and ceramic insulators should never be handled because of the danger of beryllium ingestion.

Do Microwaves Destroy Nutrients in Food?

What about the nutrients in food? Do microwaves actually make our food unhealthy for us to eat? This has been investigated many times by scientists and the facts on this subject are quite clear. Studies have been conducted to find out how the different cooking methods affects the nutrient content of foods and microwave ovens are shown not to affect the nutrients in foods as long as it is used properly. Of course, an exception is made for the nutrients are that lost by any cooking of the foods, including conventional methods besides the microwave.

Most of the time, foods do not lose any more nutrients than any other cooking method, but there are two exceptions. One, if you microwave something while in water, you are losing much of the nutrients found in those foods. That’s why most instructions tell you to boil the water first and then add it to the food. The second exception is human breast milk, which will lower the baby’s immune system if microwaved.


The bottom line here is that microwaves are not dangerous, harmful or bad for us, and they are perfectly safe for food as well. They are also extremely convenient and very inexpensive and if you use them properly, they will heat up your food without heating up the container you put them, make popcorn in minutes and allow you to have a cup of instant coffee in about ninety seconds. Microwaves are one of the greatest inventions of the 20th century and their popularity can be seen by the huge number microwavable foods on the market today.