Occasionally I receive doomsday emails about health issues. Most recently, the subject was microwaves and their inherent evil. I have been exposed to anti-microwave opinions for some time, most of which have been non-convincing. Arguments such as "it changes the chemical structure of the food" have left me scratching my head. I call that cooking. "They use radiation" is also a bad argument, because radiation isn't inherently bad, nor are the different wavelengths equal. Conventional cooking uses radiation, albeit a different flavor. It was with these nonsensical points by the anti-microwavists that I read the recent email. Attached were links to numerous web pages with plenty of arguments like those mentioned above, but I was also able to find some substantial evidence instead of just opinion and ignorance this go around.
One of the favorite citations of these websites is the case of a woman who was killed after recieving a blood transfusion. The blood was heated in a microwave oven by the nurse. The claim is that microwaves do "something different" because blood is regularly heated by other methods before being administered to a patient. Well, anyone who is familiar with microwaves knows that they don't heat evenly and that hot spots are created. It seems pretty evident to me that the blood probably got overheated and the cells were lysed, something that could just have easily occurred by carelessly heating the blood another way. The nurse clearly acted thoughtlessly, but the microwave is not to blame. Upon further investigation, I found that there was reason to believe that the woman died from a blood clot rather than the lysed blood, something the sites fail to mention.
http://www.museumofhoaxes.com/hoax/weblog/comments/3142/A frequently cited study appeared in
Pediatrics
http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=1557249&dopt=CitationThis information actually comes from what I believe to be a more credible source than random people on the internet and is less subjective. In this study, anti-infective factors in human milk, namely IgA, were reduced to varying degrees after being heated at different settings in a microwave. Subsequently, E. coli growth increased after incubating the microwaved milk when compared to the control milk.
Again, is seems like overheating is the underlying issue here, although even at low settings the milk was affected. It would be interesting to do this study side by side with human milk heated in other ways to determine if the IgA is just really sensitive to any heat at all or if microwaves are actually to blame.
One claim I read deserves consideration, if it is true. I was unable to find the information on the study, but it claimed that "increase of leukocytes with the microwaved foods was more pronounced than with all the other variants." Additionally they claimed, "Common scientific belief states that cholesterol values usually alter slowly over longer periods of time. In this study, the markers increased rapidly after the consumption of the microwaved vegetables. However, with milk, the cholesterol values remained the same and even decreased with the raw milk significantly."
The sites tend to leave out findings like the following, which I found on
wikipedia:
"Cornell University scientists looked at the effects of cooking on water-soluble vitamins in vegetables and found that spinach retained nearly all its folate when cooked in a microwave, but lost about 77 percent when cooked on a stove. They also found that bacon cooked by microwave has significantly lower levels of cancer-causing nitrosamines than conventionally cooked bacon."
The one thing that really caught my interest, and once again, it is entirely dependent on the veracity of the site, is this:
http://www.execonn.com/sf/The link is to a site about a 6th grade science project where plants were watered with microwaved and regular water. You guessed it, the microwaved water-fed plants didn't do so hot.
So, there is some of the evidence that is out there from sources of varying degrees of dependability, but nonetheless interesting. In the meantime, I'll keep warming up my leftovers the fast way. Check out this link for the general anti-microwave consensus:
http://www.nexusmagazine.com/articles/microwave.html