As we know EM waves are widely used in our life. One of the common use of these waves is in the kitchen and specially microwave.is it really Carcinogenic?
No it isn't. It is similar to boiling or steaming, unless you cook it too long and you start burning it. Microwaves have less energy per photon than visible light, and much less than ultra-violet, so make the molecules vibrate, not break directly, and mainly the water molecules. Vibration of the molecules is heat. If it gets hot it has the usual effect of cooking. If it gets too hot it has mostly the same effect as when cooked things get too hot.
I fully agree with Malcolm; but there are quite a few people who believe(!!!) [well we may belive in church; here we should know]that there is a difference between microwave cooked food and food cooked say on a gas flame or coal fire. And those people quote a test experiment (everyone is invited to repeat it) saying when a cat has the choice between microwave oven heated milk and milk heated (up to say 30 C) on a coal for gas fire they would prefer the non microwave (ans also non induction oven) heated one.To be tested..and publish your results here
I am an old RF and microwave engineer also working in medicine for decades. I did a lot of medical analyses on microwave effects on the human body and can tell you that microwave is very harmful to people. Yes, it moves molecules and produces heat but significant harm goes from the energy transfer that microwave brings to the biological cells. It is well proven that microwave radiation may result in cancer and it is why any microwave oven has a special protective shield on the oven door glass. But this shield is not enough, therefore never watch cooking through the window when the oven is on. Safe is to stay at least 1 meter from the oven. It ensures microwave energy attenuation of about at least 40 dB (10 thousand times!). If you need to be closer to the oven, stay from the control panel side, usually, it is located on the right. The magnetron inside sends energy into the chamber and by staying on the control panel side you will be in the opposite direction.
Sam's view is what I would call a fringe view, among the "few" Fritz Caspers refers to. I too worked in microwaves at high and low power with radar and was and still am responsible for the safety of other people and myself around microwave radiation, for 40 years. There have been very few reliable cases of harm from microwave radiation reported, except in a few cases that involved "cooking" of body parts by accident. I keep on searching for cases of microwave injuries, and by microwaves I include phone frequencies.
The door of a microwave oven is very good at stopping microwaves, and lets out a lot less than what your phone puts into your head when you use it.
It can be calculated and measured, and is.
Some of the very few injuries have been when people have removed the switch that stops the microwaves when the door opens, so they could put things in and out quickly. That changes the oven into a high power microwave antenna, when it is on with the door is open. People have cooked parts of their arms doing that, with lasting nerve damage.
Some people claim to have physical and mental problems caused by microwaves, but usually these seem to be caused by worry about them rather than the microwaves themselves, and when it has been tested it has been found that the presence of a microwave (or mobile phone) antenna can bring on the effect by itself, whether or not it is switched on.
At Comment by Malcolm: Yes there certainly is a widespread "nocebo " effect related to anything that has the name microwave..a psycho problem.
On the other hand ..if it turns out that the "Cat and milk" experiment is really reasonably reproducible (and everyone can do it at home) under controlled conditions it would certainly be interesting (of course this would not imply any danger or hazard a priori.
Let us unpack the question. It is about food being carcinogenic.
1) Microwave ovens use frequencies of about 2.45 GHz.
2) Food is generally high in water, and water has an absorption coefficient of about 0.65/cm at this frequency at 20 C, with the absorption depth increasing with temperature rise.
3) At 2.45 GHz, the photon energies are about 1/1000 the of the energies of Van der Waals forces and 1/10,000 the energies of the weakest hydrogen bonds.
What this means is, that despite claims to the contrary, at 2.45 GHz only heating matters, there is not enough photon energy for a non-thermal effect.
This does not mean “freedom”, getting hot is no small matter.
The heating is more uniform than boiling or frying, as the heat is generated within the food itself. Conduction heating such as frying, baking or grilling will produce temperatures of above 100 C on the outside whilst the inside is still cold, so the outside dehydrates and becomes crispy.
Under normal conditions, microwaves will only produce boiling, unless one has a very high performance unit.
The insidious problem of microwaves leaking and producing heating in deeper tissue is, indeed a problem. Our physiology is geared towards detecting conduction and IR radiant heat, and the skin is tough stuff. The effects of inadvertent heating of deeper tissues is not settled, but eating microwaved food is OK. It just does not taste any good…
Zoltan Vilagosh , Very helpful, but not all microwaved food is nasty! Some food tastes better microwaved, other food tastes worse, and some tastes the same. That is something each person needs to decide for themselves! It can also be a matter of scale. Some meals (using fresh produce or frozen), or parts of meals, that cook very well for one person do not do so well when there is twice as much.
Interesting discussion, always. The vast majority of scientific research conducted to date suggests that the low levels of microwave radiation produced by microwave ovens do not pose a significant health risk to humans. The World Health Organization (WHO) states that there is no evidence to suggest that exposure to the levels of microwave radiation emitted by microwave ovens has any adverse health effects.
Welcome, here the link: https://www.who.int/news-room/questions-and-answers/item/radiation-microwave-ovens
I just realized that I answered the wrong question. I thought about the harm from microwave ovens to the human body due to microwave radiation. However, the question was about damage from food cooked in a microwave oven. I think that microwave oven does not provide any harm to food and, consequently, to the human body. There may be very rare cases when food has very little water only in some parts of it. In this case, may be possible burning of these small parts. It will create burned protein and these small pieces may be cancerogenic.
Dear Sam
your new viewpoint is interesting for me; but my question was about using microwaves radiations,as you thought firstly.
Dear Hamideh,
The question was about the effects of microwave radiation on food, not on the human body. The major difference is that in the food we do have not alive biological cells but in the human body cells are alive. The interaction of microwaves with live and dead cells is completely different. For food is answered here. For humans, there is no simple answer. It depends on many factors and must be analyzed for each case separately.
Dear Sam
I'm so grateful about your exact answer. I know some factors like age, genetics,intensity of waves. do you know some others?
Hamideh,
There are so many factors. Important is how much water (liquid), and fat are inside the tissues. Skin conditions, etc. Even ambient air parameters can affect microwave interactions. It is used in microwave medical imaging because it changes the picture and provides additional information. The most important factors - are the dielectric constant of organs, tissues, skin, etc, and their corresponding volume. You must account for all possible reflections from all the changes in dielectric constants and geometries. Moving also changes the picture. It is really complex stuff. However, analyses are doable if you have good tools.
Dear Rahmati
there is no any harm to the human body if using microwave radiation-cooked food. It is very important to understand whether food is cooked well or not. Microwave is only hazardous if it exposed to the human body. It is very good to cook with the microwave because it easily kills the microbial
Wiltshire Farm products are all cooked in the microwave. I eat these most days!
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