Myths and truths about the microwave oven


The microwave oven is currently one of the most popular household appliances around the world; but, for a long time, many things have been said about it. So, to what extent could all of this be true?

Like many other inventions, the microwave was created almost accidentally by scientists dedicated to researching war technologies. Thus, in 1946, Dr. Percy Spencer, an engineer with the Raytheon Corporation, tested for the first time what would be the microwave oven in the future. This invention was born from an experiment that was part of a research project with a technology called a magnetron, which was used to build a new type of radar.

Although the manufacturing of the microwave oven began in the 1950s, it was not until the 1970s that it was introduced to homes in the United States, and in the late 1980s it was already present in 25% of them. Today, the microwave oven is present in at least 90% of homes in the United States and Europe.

Nowadays, this appliance is considered a popular, fast, and effective cooking method worldwide; but its operation still raises doubts in the general community, either due to ignorance or speculation. To help you better discern on this topic, here we answer some of the most frequently asked questions about this device and its effects.

Does the microwave oven produce radiation or not?

There are much confusion and speculation on this issue. For example, some people say that the microwave oven does not emit radiation because the magnetron does not produce any. Others say that they do not produce radiation due to the metal mesh that surrounds electromagnetic waves and does not allow them to go out.

Now, keep in mind that microwaves are high-frequency electromagnetic waves, similar to those of a mobile phone, cable television, or radio. Also, the oven is a device that works with electricity and produces electric and magnetic fields. So, that means the microwave oven does emit non-ionizing radiation that expands in the kitchen when you are using it.

Unfortunately, many associate radiation with radioactivity, toxic waste, radioactive accidents, etc. But, beyond those conceptions, this term really refers to the propagation of energy in the environment. In other words, radiation can be good or bad.

Is the microwave oven frequency much higher than that of other devices?

Microwaves are high-frequency waves and, like visible radiation (light), they are part of the electromagnetic spectrum. These are used primarily for TV broadcasting, radars for air and sea navigational aids, and telecommunications. They are also used in industry for processing materials, in medicine for diathermy treatment, and in kitchens for cooking food. 

The magnetron is a device the oven uses to produce the microwaves that, in a metal box, are capable of heating food. This mechanism has a frequency of 2.4 GHz, which means that you are daily heating your food with waves at frequencies very similar to WiFi.

Does the microwave oven make food less suitable for consumption?

The claim that food cooked or heated in a microwave oven is harmful has been studied since the 1980s, but is still in the process of being validated. However, a large number of preliminary studies by scientists around the world indicate that there is a degradation in some foods.

Dr. Hans Hertel, co-authored with Dr. Bernard Blanc of the Swiss Federal Institute of Technology and the University Institute of Biochemistry, was the first to study the effects of microwaved food on blood and human physiology. Their study concluded that using the microwave oven changed the nutrients in food and these changes also occurred in the blood.

Similarly, a study published in the November 2003 issue of the Journal of the Science of Food and Agriculture found that broccoli heated in the microwave with a little water lost more than 97% of its beneficial antioxidants. Another 1999 Scandinavian study found that cooked asparagus had a reduction in vitamin C caused by the microwave.

A Japanese study also showed that just 6 minutes of microwave heating transforms up to 40% of the vitamin B12 in milk into an inert form. Additionally, a recent Australian study showed that microwaves cause a higher level of “protein unfolding” than conventional heating. Also, regarding breast milk, in 1992 it was found that heating it in the microwave can make it lose the activity of lysozyme, antibodies and promote the growth of pathogenic bacteria.

Although many of the above studies are not recent, and even when there is no official unified position, there is enough evidence that proves that using the microwave oven can degrade food quality.

Does the use of the microwave oven cause damage to health?

As we have previously mentioned, the microwaves are enclosed in a metal mesh that retains them; but what comes out of the microwave are the electric and magnetic fields associated with the use of electricity the oven takes to operate. This is what can cause adverse health effects.

For example, it is recommended that people with pacemakers should not be near a working microwave oven, as the electromagnetic field could affect the device. However, it’s important to note that, today, pacemakers have also evolved and are not as vulnerable as they once were.

Additionally, there is evidence that this same frequency also causes an increase in blood sugar levels on susceptible individuals; this could be the cause of a type of diabetes.

Does the microwave oven cause cancer?

Food cooked or heated in the microwave oven has not been proved to degrade to the point of being carcinogenic or harmful to health. However, it is important to highlight that the IARC (International Agency for Research on Cancer) has recently classified artificial electromagnetic waves as type 2B carcinogens. So, indeed, its prolonged use could have long-term effects on the development of some type of cancer, but not precisely because of food, but because of the artificial electromagnetic fields it produces.

In conclusion, harmful biological effects were found that are still under investigation; therefore it is very important to consider the safety of this common appliance, especially in restaurants and fast-food chains that use it frequently throughout the day.

Has anyone considered the biological effects caused by these devices and the high-intensity field emissions that extend several meters outside the equipment in kitchen operators? We can associate some related to the fields generated around the oven, which although we know they are not exactly microwaves (because these are trapped inside the metal box to heat the food), by the studies we performed in the NOXTAK labs, we know the oven emissions refer to two things:

1. Electric and Magnetic Fields of Extremely Low Frequencies (ELF) related to the current the oven uses to operate.

2. A high magnetic flux measurable in low-frequency (LF) milligauss.

In our next article, we will delve deeper into the best ways to use this everyday gadget safely and healthily hand in hand with our NOXTAK technology. 

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