Nutrition Myth Busting : Microwaves Hurting Food

Nutritionist Mythbusting

There are rumors about diet and health that are commonplace through either centuries of wishful thinking or just people trying to sell something to the public masses. Some of them are as old as 1820, such as the vinegar and water diet. Others are recent, like the keto or the gluten-free diet. Either way, these misconceptions have led to the loss of money, health, and in some cases even life. So, what better way to advocate nutrition than to put some of the health and diet rumors to bed?  That is what we are going to look at, as we dive into the madness-inducing world of nutrition misconception. And what better place to find the answers than a nutritionist blog?

Can Microwaves Damage your Food?

When a new concept or method for a tried and true tradition arises, there are going to be naysayers that exist. Especially among the scientific illiterate. In the case of the microwave, while it has become a kitchen mainstay for decades, there are still those who criticise the idea of microwaves being used to reheat both foods and liquids that you are planning to ingest. The only way to gain a better understanding of how a microwave works, and if it is actually harmful, is by looking into the scientific research about it.  Before that, let’s delve into…

The History of the Microwave

The microwave oven was built post-WWII by a self-taught engineer, Percy Spencer. Until then, high-frequency radio waves had been utilized and experimented with since the 1920’s for various military purposes. Such examples include the radar technology that is used to this day and the heating up of medical equipment for sterilization. The earliest presentation of such a thing had predated the invention as an exhibit during the Chicago World’s fair in the 1930’s for heating up sandwiches.

However, it wasn’t seriously thought of as something that could heat up food, until Percy Spencer noticed the stray waves heating up some chocolate he had put in his pocket (or at least that is the rumor that circulated about its origin story). The first food he deliberately cooked was popcorn. The second had been an egg, which exploded during the experimentation.

The company that Mr. Spencer had worked for, Raytheon, caught wind of this and started selling it commercially in 1947. It was improved upon by other contributors that worked for the Raytheon company, such as David Copson, Marvin Bock, Lawrence Marshall, and Fritz Gross. It did not have a public release until 1967.

Difference Between Radiation and Radioactivity

Soon after the release of the microwave, it had met with criticism by people concerned about public health and safety. This was because of the process that the microwave used was known as radiation. People were immediately concerned that radioactivity would seep into both the food and the environment when it leaked. This would be an impossibility. This is because radiation and radioactivity are not the same things.

Radiation is the process of thermal energy. It does not ionize tissue and passes through both most objects including, glass, plastics, and other forms of solid matter. The wavelengths are of a lower frequency and longer length compared to the rest of the lengths that can be measured

Radioactivity is the process of an element ionizing its surroundings through gamma waves. Increased exposure to both these gamma waves increases the ionization of organic matter causing the rapid growth of cells, aka cancer.  Gamma waves are of a much higher frequency and have a much shorter wavelength.

Not only are they different processes,  but they are entirely different wavelengths. They are literally on the opposite sides of the scale.


wavelength, microwaves



How Did The Rumors Start?

There has been fascination and anxiety from WW2, all the way until the end of the Cold War about nuclear energy and reactions. People lived their lives terrified of atom bombs and political turmoil. Naturally, that sort of alarm combined with scientific illiteracy would result in a rumor like this from spreading. Especially since both scientific principles sound the same to the layman.

However, this rumor continued to persist in spite of available information from the age of the internet, after the Cold War was over. What happened? You can thank Dr.  Joseph Mercola and Hans Hertzel for that one. The first of the two is an alternative health con artist with money tied to the presentation and spread of the rumor that microwaves are dangerous. Even the FDA outright sent a cease and desist letter for his unsubstantiated marketing claims. 

Hans Herzel had originally published a paper stating that ” Consuming microwaved milk and vegetables could begin a process that leads to a cancerous condition”. This publication hasn’t been reviewed, nor replicated. That is the most unscientific article regarding microwaves to date.

There is a danger of carcinogens if you use certain types of plastics with the microwave, such as styrofoam. There is also a risk of catching the device on fire if you stick metal in it. These are things you must be aware of before heating anything up in it.

Can Microwaves Remove Nutrients?

This is the other pervasive rumor regarding microwaves. Unfortunately, this is just about as false as you can possibly get.

Because cooking anything at all will decrease nutrients in food.

“There is no specific harm of microwaving with regard to nutrient levels,” says David Katz, MD, director of Yale University’s  Prevention Research Center. “In fact, any type of cooking can chemically change a food and it’s nutrient content: Vitamin C, omega-3 fats, and some bioflavonoid antioxidants are more sensitive to heat in general  Nutrients from veggies can also leach into cooking water. Since you’re apt to use less water when cooking in a microwave, your food might even be better off.”

So, according to a director from YALE, if you have a shorter cooking time and use less water, you are preserving more nutrients. 


This post and more like it that’s done for the Nutritionist Bekah Dewitt of Bek’s Bites in Huntsville Alabama. Call me if you want to set up an appointment.