Last Saturday, Ruth posted concerns about the use of microwave ovens. While I have no problem with you choosing to spend time reheating food on the stove top, I would say you shouldn’t go throw your microwave in the junk pile just yet.

First, let’s tackle that scary story about the woman dying from a transfusion of “blood altered by microwaves”. Sounds like a plot for a horror movie, doesn’t it? Well there truly was a court case and the plaintiff did allege that the microwaves made the blood unusable by the human body. The defendants argued that the woman died from a blood clot and not the transfusion. The defense made a strong enough case that the jury found in their favor. (See the court document from one of the civil suit appeals.) Now in the court document, it states that heating the blood in the microwave causes the cells to rupture and release large amounts of potassium, and excessive amounts of potassium can be fatal. That’d be a valid concern — if you were planning to reheat a steak and then mainline the blood via IV. However, you’re planning to consume the stuff you put in the microwave, not inject it!

So first, let’s take a look at what exactly microwaves are. You’ll have to stay with me as we’ll be discussing some science-y stuff. But before you tune out, realize that an understanding of some science is what keeps you from thinking the Earth is flat or thinking that actors actually live inside your TV.

Microwaves are part of the electromagnetic spectrum. This is basic stuff if you’ve ever taken a chemistry, astronomy or maybe even physics course. Now take a look at the diagram above. You will see that everything from radio waves, to visible light, to UV rays, X-rays and microwaves are part of this same spectrum. The difference in each is what their wavelength and frequency is. From the left side of the spectrum are the largest waves, AM radio waves are larger than FM and that’s why you can often hear an AM signal much further out of town than you can FM. On the other side of visible light are the ionizing forms of energy, very tiny waves such as x-rays and gamma rays, which are what truly qualify as “nuclear” energy. These are what are emitted by radioactive substances, among other harmful particles.

As you can see, microwaves are rather large in size and that is why you have that grating with small holes in your microwave oven’s door. Those small holes are enough to block the waves from escaping and yet large enough the visible light waves can get through so you can see your food. Granted, an occasional wave may escape, but that is why you don’t want to put your face two inches away from the door. (The waves lose their potency beyond that distance. The same principle applies to x-rays, which is why the doctor snapping your pics backs up behind a wall to take the shots.)

Now that we know what exactly a microwave is, how does it do that magic to heat our food? Well first, we need to consider what exactly heat is made of. Temperature is caused by the movement of particles of matter. The faster those particles move, the greater their kinetic energy and hence the “hotter” they feel. When you step out into the sun, the variety of rays that hit you (UV, infrared, etc.) all cause the molecules in your skin to move faster and you feel warmth. Conventional ovens work by raising the air temperature and cooking the food from the outside in. The molecules of the food are caused to move faster and you experience this as warm (or hot) food. Microwaves have an interesting property in that they are absorbed by water, fats and sugars which cause those particles to move faster and to get hot. Since the microwaves can get to the particles throughout the food, it is faster than a conventional oven which first has to heat the air in the oven and in turn pass that heat into the food via convection.

Now on to the $30,000 question: does the microwaving change the food? Well the answer is… sorta. Since the water molecules are “excited” and caused to move faster, this may cause damage to water-based vitamins. But guess what? The same thing can happen if you overcook your food on the stove! So take care not to overcook your foods and in fact, heat only when necessary. I wouldn’t recommend dishing out the huge price for one of those Flavorwave ovens due to paranoia. Oh, and that other urban myth about microwaves “resonating” or somehow staying in your food? Absolute garbage. No more can a microwave stay trapped in your food than you can hold onto an x-ray from the doctor’s office and spit it out later when you get home. Just remember, it’s easy to be scared of the unknown. Now that you know a bit about microwaves, you can make your own educated decision on whether it’s too dangerous for your own use. Personally, I would say if a microwave will get you to eat homemade meals rather than dining out, it’s definitely a step in the right direction.

More reading on the subject: Microwave Safety by Mark’s Daily Apple

WOD 3.12.10

Back Squat 3×5

Then, AMRAP 15

• Handstand Pushups (5 men / 3 women)
• 7 Squat Snatch (95 / 55)
• 10 Box Jumps 20″