Are Microwave Ovens Safe?
An examination of the various claims that microwaved food and water are poisonous.
Filed under Health, Urban Legends
| Skeptoid #80 December 25, 2007 Podcast transcript | Listen | Subscribe |
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By Brian Dunning, Skeptoid Podcast
Episode 80, December 25, 2007
http://skeptoid.com/episodes/4080
Today we're going to walk on the wild side and eat some microwaved food. You've never really lived until you've lived dangerously, so let's put our lives on the line by testing the claims that microwaved food and water are toxic.
First, a little background info. Microwave ovens work by passing microwave-band electromagnetic radiation over the food at 2.5 GHz. Molecules that are electric dipoles, of which water is the most efficient, rotate back and forth in this field. The friction between them creates heat. This is called dielectric heating. More complex molecules, which are not as clearly dipolar, are not affected. It's an efficient and clean way to heat food.
I first learned about the claims of danger from a chain email sent by a friend of mine who tends to believe anything that's anti-establishment or on the fringe. A few Internet searches of some keywords reveal a huge number of holistic, organic, and other alternative web sites repeating these same claims. Just to give you a flavor of how far-out these stories are, give a listen to this list of "Ten Reasons to Throw Out Your Microwave Oven". As I read these off, notice that not one of them makes a specific or testable claim; they are all merely scary sentences constructed using scientific sounding words. And, as you can tell from the brief description of how microwaves work, few of these have any remote connection to fact:
- Continually eating food processed from a microwave oven causes long term — permanent — brain damage by "shorting out" electrical impulses in the brain, de-polarizing or de-magnetizing the brain tissue.
- The human body cannot metabolize the unknown byproducts created in microwaved food.
- Male and female hormone production is shut down and/or altered by continually eating microwaved foods.
- The effects of microwaved food by-products are permanent within the human body.
- Minerals, vitamins, and nutrients of all microwaved food is reduced or altered so that the human body gets little or no benefit, or the human body absorbs altered compounds that cannot be broken down.
- The minerals in vegetables are altered into cancerous free radicals when cooked in microwave ovens.
- Microwaved foods cause stomach and intestinal cancer tumors. This may explain the rapidly increased rate of colon cancer in America.
- The prolonged eating of microwaved foods causes cancerous cells to increase in human blood.
- Continual ingestion of microwaved food causes immune system deficiencies through lymph gland and blood serum alterations.
- Eating microwaved food causes loss of memory, concentration, emotional instability, and a decrease of intelligence.
One clue that might encourage you to regard these claims with some skepticism is that fact that ever since microwave ovens came on the market in 1954, not one person has ever exhibited a single symptom of any illness resulting from having eaten microwaved food, or from having used water that had been microwaved. Burns are the exception, but burns are caused by heat from any source; that's not unique to microwaves. But if you believe the claims by the anti-microwave fringe, whom I call the Microwave Militia, practically everyone on the planet should be gravely ill with cancer, radiation poisoning, malnutrition, and mental retardation.
The same chain email, and many of these web sites, also state that giving a plant water that has been microwaved will kill it. There is even a series of unsourced photographs of two plants, one of which withers and dies while its sibling flourishes. The awesome web site Snopes.com tested this particular claim. They took three plants of each of several types, and watered one with tap water, one with water that had been boiled over a stove, and the third with water that had been boiled in a microwave. Unlike whoever took the pictures that often accompany the chain email, Snopes actually controlled for other variables. I'm sure you won't have to stretch your imagination very far to guess how the plants did. They all did exactly the same. Snopes has complete details and photographs on their web site. Somehow these plants managed to escape the guaranteed death sentence that believers say microwaved water carries.
This whole paranoid suggestion is based on the presumption that a microwave oven somehow changes or poisons water. If true, wouldn't you be able to perform some kind of a test on water, and see if it has ever been microwaved? Water is H2O, whether it's ever been microwaved or not. But here's an even deal for you. If you truly believe that H2O carries some permanent damage as a result of being microwaved, and that it's possible to detect this damage through any means you choose, there's a million dollars in it for you. As you may know, the Skeptoid podcast is a qualifying media outlet for the James Randi Educational Foundation's Million Dollar Paranormal Challenge. I'll walk it through for you and I'll become your biggest cheerleader. Are microwaves really a danger to humanity? If so, it would be immoral for you to do anything else but take that million dollars and use it to educate and save the world.
Probably the most flagrant error that the Microwave Militia propagates is that microwaved food or water contains what they call "radiolytic compounds" — new chemicals created by the tearing apart of molecules in a microwave. These new chemicals are said to be dangerous, cancerous, radioactive, unnatural, or otherwise harmful. This is a demonstrably false claim. Radiolysis, which is a real process and which the Militia believes creates these radiolytic compounds, is the process by which molecules are dissociated under ionizing radiation. Water can be dissociated under ionizing alpha particle bombardment, which is a natural process. Microwave radiation, as mentioned earlier, is not ionizing radiation. It is thus scientifically incapable of causing radiolysis. The differences between microwave radiation and alpha radiation are huge. With the claim that microwaves cause dissociation of water molecules, the Microwave Militia is either deliberately lying, or they are grossly ignorant of the very subject on which they claim superior expertise.
Swiss vegetarianism advocate Dr. Hans Hertel is perhaps the most vocal of the Microwave Militia fringe group. He is quoted in virtually every book written on alternative foods or holistic health. A top-selling book on Amazon called Perfect Balance, by an author known simply as "Atreya", writes:
In spite of the political pressure, Hertel has continued his studies and won the support of many other scientists in Europe for his findings and methodology. Hertel concludes that microwaved food alters the blood chemistry of people who eat it. The manufacturing companies are trying to keep this information suppressed through court orders.
Dr. Hertel seems to have managed to gain this claimed following even without producing the most basic of information that prospective groupies should request: a specific, testable claim about what this change in blood chemistry might be; or a single victim. He is best known for his most publicized test. In 1989, he and seven fellow vegetarians confined themselves to a hotel and consumed only milk and vegetables, prepared in different ways, for two months. When he emerged, he announced his results: That microwave ovens cause cancer and degenerative diseases, despite no cases of cancer or illness among he or his group. His research, if you want to call it that, was never peer reviewed or published in any reputable journal, and yet it has become the foundational magnum opus of the anti-microwave agenda.
You'll also find that there are a large number of studies out finding changes to the nutritional content of food that has been microwaved, and the Microwave Militia loves to point to these. Chemical reactions happen whenever any food is cooked, so this has more to do with cooking than with the cooking method. Moreover, such changes are generally well below any perceptible threshold, and have always been found to be safe.
The Microwave Militia also makes claims such as microwave ovens are illegal in Russia or other parts of Europe. This is just a straight-up lie. Microwaves are perfectly legal in Russia and everywhere else in Europe. In fact I was not able to find a single country in the world that bans microwave ovens. They're regulated, of course, like all electric appliances; but regulation should not be mischaracterized as a ban.
So what's the sum total of our evidence? Billions of people have been eating microwaved food for decades, with no ill effects, and no plausible expectation of ill effects. The best evidence put forward by anti-microwave activists is based on shameless lies and irresponsibly bad science. Thus, a truly skeptical process leads us to the conclusion that there's nothing at all wrong with microwaving your food. However, I'm drinking coffee right now made from microwaved water, and it's entirely possible that this has caused profound mental aberration, and made me spout nonsense.
© 2007 Skeptoid Media, Inc.
References & Further Reading
Dr. Hans Hertel. NEXUS Magazine. Mapleton, Australia: Mercola, 1995. Volume 2, #25.
Kleinerman, R.A., Linet, M.S., Hatch, E.E., Tarone, R.E., Black, P.M., Selker, R.G., Shapiro, W.R., Fine, H.A., Inskip, P.D. "Self-reported electrical appliance use and risk of adult brain tumors." American Journal of Epidemiology. 15 Jan. 2005, Volume 161, Number 2: 136-146.
Latimer, Joan M,, Matsen, John M. "Microwave oven irradiation as a method for bacterial decontamination in a clinical microbiology laboratory." Journal of Clinical Microbiology. 1 Oct. 1977, Volume 6, Number 4: 340-342.
Mikkelson, Barbara, Mikkelson, David P. "Boiling Point." snopes.com: Microwaved Water - See What It Does to Plants. snopes.com, 22 Aug. 2006. Web. 5 Dec. 2009. <http://www.snopes.com/science/microwave/plants.asp>
Mudgett, R. "Electromagnetic energy and food processing." Journal of Microwave Power and Electromagnetic Energy. 1 Dec. 1988, Volume 23, Number 4: 225-230.
Welt, B. A., Tong, C. H. , Rossen, J. L., Lund, D. B. "Effect of microwave radiation on inactivation of Clostridium sporogenes (PA 3679) spores." Applied and Environmental Microbiology. 1 Feb. 1994, Volume 60, Number 2: 482-488.
Reference this article:
Dunning, B.
"Are Microwave Ovens Safe?" Skeptoid Podcast. Skeptoid Media, Inc.,
25 Dec 2007. Web.
21 May 2013. <http://skeptoid.com/episodes/4080>
Discuss!
10 most recent comments | Show all 110 comments
Never trust anything that's marketed on a t-shirt.
'nuff said!
Keith, Sussex, UK
January 07, 2013 4:24am
I'm a mother looking for info on microwaves & am frustrated by how hard it is to find good info on this & am wondering if you can help clarify a few things for me.
I don't really enjoy cooking, specifically I hate the big mess and I often like the fact that it's so much cleaner. The things I cook most in the microwave are eggs, sauces, risottos, rice, pasta & steam veg. I have also on occassion poached/steamed chicken & fish. I also defrost & reheat food in it every day. Sometimes I must admit have accidentally overcooked food in it & on the stove.
I'm trying to figure out how much I should use it moving forward. It still sounds like the jury's out on whether it's 100% OK, there's no 100% proof that it's NOT OK so should I go ahead & use it as much as I do? Any advice? I don't want to listen to quacks but also if there are some genuine concerns being suppressed for commercial reasons, I don't want to ignore them either. Does the amount you use it or what you use it for make it more or less safer?
Here are some of the claims that I want to know if they have ANY truth to them or not:
- the cats dying from microwaved cat food in Russia?
- were they EVER banned in Russia?
- was Hertel gagged?
- 'protein unfolding'?
- if it changes the composition of breastmilk, does it do that to formula & all dairy?
- the woman who died from her blood for a blood transfusion being microwaved?
- why do ppl say only use it to reheat if it's safe?
Tks for your help.
Ggirl, Sydney, Aus
February 12, 2013 4:07pm
Wow, this article is very irresponsible. But then again i guess it would be considered your personal opinion and not scientific fact.
The fact is that unless a real "study" is preformed, no one can say either way about the dangers of microwaving.
And saying that people have been using them for centuries without sickness is just wrong. People get sick with cancer and stuff all the time. Maybe the microwave is to blame or maybe it isn't, but you don't know that. Just as I dont or anyone else. If we really "knew" what caused cancer, it would be easy to judge a microwave...but we dont!
You seem to have a bias already and the article is most definitely slanted to show that. But i guess your own opinion doesn't need to be objective as long as your readers understand that you may not know what you're talking about.
Mags, LA,US
February 19, 2013 9:29pm
Mags, you should read the six reference at the end of the article. Everything written in the article has been test over and over again by scientist from all over the world. You can choose not to believe them, it doesn't change the fact that it's safe to use a microwave.
Ggirl, Microwave only heat aliment, nothing else. It wont change the composition of breastmilk or formula. It will only make the water in aliment move so fast that they produce heat. The worst risk of the microwave is to burn yourself when you empty it
Benjamin, Montréal/Canada
February 20, 2013 2:11pm
Here's a link to a study done to feed rats irradiated foods. In the experiment rats given irradiated foods, and exposed to cancer, got cancer, at a much higher rate than the rats exposed to cancer but not given irradiated food. Our country's FDA is ready to permit even higher doses of radiation to our food supply, and add other meats, pountry, and other food products to the already existing list, so we can eat food that would have been potentially harmful (or maybe should have been thrown out?)because its harmful bacteria will be killed. Would anyone like to become part of a human experiment on irradiated foods? Without even signing up, or being part of a controlled group, USA consumers are about to become the test group. http://www.ncbi.nlm.nih.gov/pubmed/12734067
Oh well, another one bites the dust...
dan gruber, peoria/il/usa
March 13, 2013 8:42am
dan gruber, "irradiated food" is the process by which foods are exposed to specific doses of safe levels of IONIZING RADIATION which destroys potentially harmful bacteria and microorganisms.
Microwave ovens use NON-IONIZING electromagnetic radiation which in and of itself does not cause changes to the structure of molecules as does ionizing radiation/
Joffbaum, NYC
March 19, 2013 11:41pm
correct Joff but not quite..have you ever cooked in a microwave? that is making a fair few changes.
just being a pedant..
I wish folk would get a little more with it tho, What are the levels of free radicals in any food by comparison?
You are not adding any radiation to your food by irradiating it but you sure are adding a great carcinogen load in many of the preserving processes.
Guess we just have to forgo our schnitzen....gruber
Another blazing saddles gag!
Mud, Pho s Brewery NSW, Oz
March 27, 2013 9:18am
I find it immensely humourous that many that deplore microwave cooking will imbibe in drinking unkonwn additive to beer, or wine. Or possibly will smoke.
c ra z y\
Alrady, phoenix
April 02, 2013 11:28pm
Some of the information in here about what microwave opponents claim isn't even accurate. For one thing the author affirms that microwaves are not banned in Russia, fair enough, no one said they are NOW. the Russians banned microwave ovens in 1976, later lifting the ban during Perestroika. The ban was the result of 20 years of Russian research.
Furthermore the author discusses the many ailments that Dr.Hertel believes may be linked to microwave cooking, which would theoretically be long term effects which obviously aren't going to take place in the span of two months (the length of Dr.Hertel's study).
Yet he makes no mention of the testable changes in biomarkers that Dr.Hertel claims to have observed in his study.
Hertel’s conclusions were that microwaving food resulted in:
• Increased cholesterol levels
• Decreased numbers of leukocytes (white blood cells), which can suggest poisoning
• Decreased numbers of red blood cells
• Production of radiolytic compounds
• Decreased hemoglobin levels, which could indicate anemia
Whether true or false, one would think that with results as alarming as these a responsible government would fund follow up studies to see if the results are reproducible.
marcus volke, ballarat
April 23, 2013 5:57am
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I'd say, see a doctor Jeffe.
Mud, At virtually missing point, NSW, OZ,
January 03, 2013 2:18am