MICROWAVES: PART II

ARE MICROWAVES CARCINOGENIC?

Before we dive into this conversation, I have to remind you that we talked about microwaves in our last post. We wanted to know whether microwaves "killed" the nutrients in our food, rendering our meals useless (takeaway: no, not always). Today we wanted to specifically look at microwaves as a possible carcinogenic factor and discover whether microwaves cause cancer. In order to answer this question, we first need to understand how a microwave works.

Imagine the box above represents a microwave.  Here you can see one electromagnetic wave representing the many heat waves that travel through the box to heat the food. This is RADIATION. 

I would say that the very term "RADIATION" is what causes people to fear microwaves. In order to relieve ourselves of any fear, we have to understand it. So let's break it down.  

RADIATION is just "energy that comes from a source and travels through some material or through space" (REAC/TC). With this definition, the wave above is that ENERGY (heat) that travels from the SOURCE (microwave) to the MATERIAL (food). 

So that's what we're talking about when we talk about RADIATION: the waves that travel through the food fast enough to heat up its molecules. 

Notice also that with this definition, we could describe the heat produced by a convection oven the same way! As RADIATION. Does that remove some of the fear? 

Alright, but we still can't ignore the concern specifically with MICROWAVE RADIATION (the heat waves produced by microwaves). What is that? Well, you see, lightwaves move at different FREQUENCIES. The kind that we have to worry about are the HIGH FREQUENCY waves. These include X-RAYS and UV RAYS, (which makes sense since you've probably heard that we shouldn't be exposed to too much of these kinds). 

Why are HIGH FREQUENCY WAVES more "dangerous"? Because a higher frequency wave has the potential to knock off electrons from an atom. This is called IONIZING RADIATION. (Need a visual? Check out the electrons circling the atoms in COFFEE: PART III). In a human body, IONIZING RADIATION can damage the DNA in our cells. And if a cell with this damaged DNA does not die, but instead replicates uncontrollably, it is called CANCER.

Unfortunately, microwave machines do use this type of heat radiation. HOWEVER, the crucial difference is this: the microwave radiation DOES NOT MAKE CONTACT WITH OUR SKIN. Unlike an X-RAY or a UV RAY, the microwaves are contained within the machine. They heat up the molecules in the food, and that is it. This is why even the American Cancer Society confidently tells us that "when microwave ovens are used according to instructions, there is no evidence that they pose a health risk to people" (ACS). 

Ta-daaa. There you go people. The only concern we have is with possible slight radiation leakage that can occur through the front of microwave machines when they age. But even with that, "federal standards limit the amount of radiation that can leak from a microwave oven to a level far below what would harm people" (ACS). As a result, we are recommended to stand a few feet from the microwave when it's on. And that's about it. 

Woohoooo. So are microwaves carcinogenic?
I think we have our verdict. 

IF YOU'RE INTERESTED: The teeniest view of how heat waves LITERALLY heat the water molecules in our food. Position 1 shows how the molecule is arranged because its charges make it attract to the wave in that first position. Then, as the wave oscillates (moves, basically) the other charges on the H2O molecules (water) move with it. SO BASICALLY this is what causes the water molecules to MOVE. And if you know anything about heat, you know that it is, in essence, molecules moving FASTER. So because microwaves have HIGH or FAST FREQUENCIES, they make the molecules move FASTER--heating up the food!

BOTTOM LINE

NO, microwaves are NOT "bad" for you. They do not inherently strip your foods of nutrients---that depends on the way the food is cooked. And often, because of the quick heating methods of microwaves, they are actually the best way to preserve the nutrients in your most nutritious foods (SEE MICROWAVES: PART I).

As far as being carcinogenic, that fear probably initiated from a misunderstanding of how microwaves heat food (radiation and things like that sound cancerous!) But, as we've learned, the greatest health risk in using a microwave is the radiation emissions from the machine (not the electromagnetic waves inside it). However, the exposure is relatively low AND drops off only a few feet from the machine. So stand a few feet from the microwave (don't sit and watch your food! I know...difficult) and you should be fine :)

SOURCES

http://www.health.harvard.edu/fhg/updates/Microwave-cooking-and-nutrition.shtml (accessed Aug. 31, 2014).
http://www.sciencebasedmedicine.org/microwaves-and-nutrition/ (accessed Aug. 31, 2014).
http://www.cnn.com/2014/01/21/health/upwave-microwaving-food/ (accessed Sept. 1, 2014).
http://www.greenmedinfo.com/blog/studies-show-microwaves-drastically-reduce-nutrients-food (accessed Sept. 1, 2014).
http://articles.mercola.com/sites/articles/archive/2010/05/18/microwave-hazards.aspx (accessed Sept. 1, 2014).
http://www.youtube.com/watch?v=kp33ZprO0Ck&list=UU2bkHVIDjXS7sgrgjFtzOXQ (accessed Sept. 20, 2014).
https://orise.orau.gov/reacts/guide/define.htm (accessed Sept. 20, 2014). http://www.cancer.org/cancer/cancercauses/radiationexposureandcancer/radiofrequency-radiation (accessed Sept. 20, 2014).