by Maria Teresa De Donato, Ph.D., RDN, CHom

Despite the extensive use of microwaves that has been taking place over the last few decades, the evidence proves that they are not safe at all due to the potential harm they can cause to our health. As a matter of fact, though microwave ovens appeared on the market in 1947, already in 1976, they were banned by the Soviet Union. The reason for that might relate to the fact that, despite being considered valuable and indeed faster means to prepare our meals than standard ovens, cooking with them does involve health risks due to how they work and, consequently, their impact on food.

“Microwaves are, in fact, a kind of electromagnetic energy which contains a magnetron, a tube in which electrons are affected by magnetic and electric fields in such a way as to produce macro wavelength radiation at about 2450 Mega Hertz (MHz) or 2.45 Giga Hertz (GHz). This microwave radiation interacts with the molecules in food. All wave energy changes polarity from positive to negative with each wave cycle. In microwaves, these polarity changes happen a million times every second. Food molecules – especially water molecules – have a positive and a negative end like a magnet has a north and a south polarity.” (GCNM, 2008)

In commercial models, the oven has a power input of about 1000 watts of alternating current. As the microwaves generated from the magnetron bombard the food, they cause the polar molecules to rotate millions of times a second at the same frequency. All this agitation creates molecular friction, which heats the food. The friction also causes substantial damage to the surrounding molecules, often tearing them apart or forcefully deforming them. The scientific name for this deformation is “structural isomerism.”

Furthermore, although this kind of cooking is often unable to destroy parasites (Pitchford, 2002, p. 657), microwaves do change the molecular structure of the food by a radiation process through what can be defined as a ‘nuclear decay.’ 

According to the December 9th, 1989 British medical journal The Lancet, cooking with microwave ovens not only alters the food to the extent of causing “structural, functional and immunological changes” in the body but also “transforms the amino acid L-proline” (which is a non-essential amino acid) “into a D-proline,” that is a toxin affecting the

nervous system as well as liver and kidneys. (Pitchford, 2002, p. 641)

Among the many studies pinpointing the harmful effects that microwaves have on foods and health are those conducted by Dr. Hans Ulrich Hertel, now retired, who worked for many years as a food scientist with one of the major Swiss food companies doing business worldwide and who was fired from questioning specific processing procedures that denatured the food. In 1991, he and a Lausanne University professor published a research paper indicating that food cooked in microwave ovens could pose a greater risk to health than food cooked by conventional means. An article also appeared in issue 19 of the Journal of Franz Weber, stating that the consumption of food cooked in microwave ovens had cancerous effects on the blood.

Dr. Hertel was the first scientist to conceive and carry out a quality clinical study on microwaved nutrients’ effects on the blood and physiology of the human body. His study showed the degenerative force produced in microwave ovens and processed food. The scientific conclusion showed that microwave cooking changed the nutrients in the food and that changes took place in the participants’ blood that could cause deterioration in the human system. Hertel’s scientific study was done with Dr. Bernard H. Blanc of the Swiss Federal Institute of Technology and the Institute of Biochemistry.

Significant changes discovered in the blood samples taken before and confronted with those taken after the participants of the study ate the foods cooked in the microwaves and given to them included a decrease in all hemoglobin and cholesterol values (both “good,” HDL, and “bad,” LDL) and the lymphocytes, all of this indicating a degeneration process.

The radiation process characterizing the microwaves’ activity results in the destruction and deformation of the food molecules whose decay affects human biological cell structure.

Consequently, studies conducted in different countries since microwaves were invented by the Nazis to be used during the time they invaded Russia and headed toward Siberia have linked so far their use to the following health issues:

  • Formation of carcinogens
  • Decreased vitamin B complex, vitamin C, vitamin E, essential minerals, and lipotropic factors on all foods tested
  • Damage to many plant substances, such as alkaloids, glucosides, galactosides, and nitrilosides
  • Degradation of nucleoproteins in meats
  • Interference with low and high blood pressure
  • Cancer

(GCNM, 2008, pp. 30-37)

That said, if you have a microwave, try and avoid cooking your food with it but instead use conventional ovens for this purpose while limiting the use of the microwave to warm your food up for a few seconds to no more than one minute or so. The shorter your food stays in the microwave, the healthier it will be.


GCNM – Global College of Natural Medicine (2008). Nutritional Consultant Program (BSHH 401/NC13). Mod.01. Dietary Guidelines. Microwaves (pp. 30-37). Santa Cruz, CA: GCNM

Pitchford, P. (2002). Healing with Whole Foods – Asian Traditions and Modern Nutrition. (Third Edition). Part V: Recipes and properties of vegetable foods. 52. Summary. A Foundation for Immunity and Renewal: The Traditional Sattva Plan of Equilibrium and Essence. (p. 641). Appendix A. Parasite Purge Program (Shaw S. and

Pitchford, P.). How Parasites Spread. (p. 657). Berkeley, CA: North Atlantic Books.

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