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Riding the wave

To microwave, or not to microwave?

That was the question in an e-Alert I sent you last month (“Micro Management” 1/27/03) about the effects of microwave cooking on the nutrients in foods. A megawave of e-mail responses followed with questions and some additional information. So inasmuch as this subject is clearly a concern to so many, I’ll take a further look at the subject. But I’ll tell you right now – the news doesn’t get any better. If anything, it gets a little worse.


Back in the U.S.S.R.

An HSI member named Mykola says that the January e-Alert “raises more questions than it answers.” Regarding the U.S.S.R. ban on microwaves in 1976, she wonders if the ban has been lifted. And then there was the Swiss study that was deemed to be so damaging to microwave manufacturers that the Swiss Federal Court found the researchers guilty of “interfering with commerce” and fined them the equivalent of $65,000. Mykola wants to know why the legal action was so successful against the study. She asks, “Was the study flawed? I would sure like to know before I give up my microwave.”

I’ll start with the easy question: The Soviet ban on microwaves was lifted in the late 1980’s with the fall of Communism. This reversal was prompted by the rapid political changes of perestroika – not as a result of any new evidence that found microwaves to be safe. Previous to the 1976 ban, Russian researchers concluded that microwave cooking might create cancer-causing agents in food while causing a degeneration of some essential nutrients.

The Swiss study found similar discouraging evidence about microwaved food, but instead of seeing their research greeted as a breakthrough, the scientists who conducted the study were sued by the Swiss Association of Dealers for Electroapparatuses for Households and Industry (SADEHI). As I mentioned, this suit resulted in a stiff fine for the lead researcher, Hans Hertel. But according to some detailed information sent to me by an HSI member named Doug, SADEHI apparently had a very powerful and unfair influence over the Swiss court. This was later recognized when the Swiss decision was reversed by the European Court of Human Rights.

Blood revelations

To answer Mykola’s specific question about the validity of the Swiss study: Hertel’s research does not appear to be flawed at all. If anything it was far more controlled than most studies. Hertel enlisted eight subjects, who were all in their 20’s and 30’s. Each of them (including Hertel, who was the ninth subject) followed strict macrobiotic diets. In order to control as many variables as possible, the group lived in the same hotel for a period of eight weeks, and all abstained from smoking, alcohol, and sex.

In intervals of two to five days, the subjects ate specific foods on an empty stomach. For instance, on one day they would eat organic vegetables cooked conventionally; on another day they would eat organic vegetables from the same source that had been frozen and then defrosted in a microwave oven; and on another day they would eat organic vegetables cooked in a microwave oven. Immediately before and after each of these meals, blood samples were taken from the subjects.

At the end of the eight-week testing period, Hertel’s analysis of the blood samples revealed significant conclusions: blood hemoglobin levels decreased significantly after ingesting microwaved foods (both total levels and the amount contained in each red blood cell); white blood cell levels tended to increase for no other reason than foods were microwaved; microwaves altered protein molecules; and LDL cholesterol increased relative to HDL cholesterol.

Hertel found that as the study progressed the blood samples revealed anemic tendencies. That trend became increasingly more pronounced toward the end of the study.

Cold comfort 

In the January e-Alert, HSI Panelist Allan Spreen, M.D., told us about another microwave study that showed depletion of antibodies and the breakdown of enzymes when breast milk was microwaved. This is an important point for those using bottles with breast milk. It certainly must be tempting to take a shortcut when heating up a bottle for a midnight feeding, but it should be avoided. Microwaving destroys some of the critical disease fighting capabilities in human milk, eliminating a key reason people choose breast milk over formula. Plus, as with food, it creates unpredictable cold spots and hot spots. Microwaved milk that feels warm when tested, may contain hot spots that can burn a baby’s mouth.

Perhaps the only small piece of good news in this microwave discussion comes from an HSI member named Mike, who says that while he recognizes the dangers of microwave cooking, he disagrees with the idea that low levels of radiation can escape from the ovens. Mike writes: “I used to repair microwave ovens, so I’m familiar with their construction and how they work. The microwaves produced by ovens are the size of a pencil lead and dissipate very quickly. There are three interlocking switches activated by closing the microwave door. If even one of these switches fails to work, the oven will not turn on. With a properly operating oven, the door cannot be opened far enough to allow a wave as large as a pencil lead to escape.”

Mike’s reassurance is welcome. But it’s somewhat cold comfort in light of the existing studies on microwave cooking. Because even if microwaves can’t escape the oven, once the food has been altered by microwaves and consumed, we can’t escape the old adage: You are what you eat.



To Your Good Health,

Jenny Thompson

Health Sciences Institute

“The Hidden Hazards of Microwave Cooking” Acres USA, April, 1994
“Court Removes Gag Order from Swiss Scientist on Microwaved Food” Leading Edge International
“Russians Ban Microwave Ovens” Stephanie Relfe, Health, Wealth & Happiness