Photo Credit: jmv
How do microwaves work? According to the Daily Green, they aren't totally sure. That alone causes me to pause and think!
"Microwave radiation is a form of non-ionizing radiation (meaning it can't directly break up atoms or molecules) that lies between common radio and infrared frequencies. So it is not thought to damage DNA of living things, the way X and gamma rays do. Still, microwaves can obviously cause heating effects, and can harm or kill at high energies. That's why microwave ovens on the market must operate at or below strict limits set by the federal government.
Most microwave ovens hit food with microwaves at a frequency of 2.45 gigahertz (GHz) (a wavelength of 12.24 centimetres (4.82 in)). The prevailing belief is that molecules in the food, particularly water, absorb energy from the waves through dielectric heating. That is, since water molecules are polar, having a positive end and negative end, they begin to rotate rapidly as the alternating electric field passes through. That rotation is thought to add heat to the food.
However, there are some scientists who have dissented with this view, suggesting that other interactions between the particles may be responsible for the heating."
- The Daily Green 7/14/09
Just a little history for you. The microwave for the application of cooking food was discovered totally by accident. Percy LeBaron Spencer of the Raytheon Company was working with radar waves one day when he found that the waves had melted a candy bar in his pocket, which led him to experiment a bit with using it to heat food.
Do microwaves change the structure of the food? If you follow the link in the last line of the above quote, you'll find an interesting article that contained this bit of information:
"What we've got here is one of the great coal-mine fires of science--an argument that, in this case, has been smoldering for 50 years without resolution... in a paper often cited by microwave foes, doctors at Stanford University (Quan et al, 1992) reported that microwaving frozen breast milk sharply reduced the potency of the natural infection-fighting agents it contained. "The adverse effects . . . are difficult to explain on the basis of hyperthermia [high heat] alone," they wrote."
- The Straight Dope 5/6/05
It seems that it changes breast milk in some way. I didn't know that. The same article went on to point out that the type of micro-waves in a common microwave oven is not steady and often varies in intensity. You may have seen this happen in your own home when you went to heat water and it "exploded" or spewed suddenly. Apparently the water can get super-heated above the boiling point at times. This, too, causes me concern. It's just that it appears as if it isn't well harnessed. Kind of like a great experiment that "seems" safe, but occasionally it doesn't conform and does it's own thing.
So, are microwaves safe for food preparation?
Seems like no one knows FOR SURE. They think they know, they're pretty sure they know, they want to believe that they're safe, but there's that nagging little thing of a few unanswered questions they are still trying to figure out. Hmmm.
We did a little experiment in our home where we heated two cups of water to the boiling point from the same water source - one in our microwave, one in a pot on the stove. Then we put a drop of water from each on a slide and viewed the droplet under a microscope. They were not the same. The water from the pot was clear, not much there, but the water from the microwave had some dark stuff in it. My daughter took this idea to her science teacher and they repeated it at school with the same results. I'm no scientist, so I can't even begin to speculate what's going on with the microwaved water, but once again, it just doesn't seem right.
So, about 3 months ago, I put a ban on our microwave. It was only to be used when there was no other option. I thought this would be a really difficult transition for our family, but surprisingly it has been one of the easiest switches that we've made. I think it's only been used about 10 times in the last three months (to my knowledge anyway!).
We've found other alternatives to heating water, left overs, and melting butter. I think because we've switched from plastic to glass containers, it's been pretty easy because I can just put the left over in the oven and let it heat along with the oven. No extra dishes to clean. Grant it, electricity would be better used if we had a small countertop oven, but I wanted to see if we could live without the microwave before I invested in another appliance. I'm not sure even the countertop oven is necessary at this point.
If one wanted to make an argument for or against microwaves, it would be easy enough to do so because there are websites galore on the internet that lean one way or the other. But if you are using your microwave under the impression that there is NO debate going on out there and that it MUST be safe because they sell them and the government says so, then you better think twice. It just isn't that cut and dry.
What do you think? Anyone a scientist out there?