When I was growing up, my mom was really nervous about my sister and I standing too close to the microwave. She was afraid that there would be stray radiation when we were heating up food that would be harmful. As a kid, I always loved to watch through the front window as the bubbles formed, the cheese melted, and the chicken shriveled up. I thought it was all very fascinating since as far as I could see, the plate was just turning in a circle.

Back in the 50’s when microwaves were an up-and-coming technology, I’m sure that the risk of stray radiation from microwaves was a lot higher — and that’s probably where my mom was coming from when she would caution us against standing too close. But nowadays, the machines are built to be much safer, with layers upon layers of protective material. So, I’m not too concerned about zapping my tea while I’m messing around nearby in the kitchen.

In fact, I’m not too concerned about much of anything when it comes to microwave ovens. That is, except for flavor and texture. My husband and I don’t use ours very much at home because we find that pizza ends up soggy, steak gets tough, and pasta becomes gummy. Things also just have a more vibrant and delicious aroma when they’re reheated on the stove or in the regular oven.

But there is something that makes me slightly less inclined to use microwaves for health reasons: the microbiome

Microwaves vs. The Microbiome

When I was in college, I took a course that was all about microbiology and food. We focused on learning about food-borne pathogens like Salmonella and E. coli, and all the other unfortunate things that make our food unsafe. We talked about safe storage and cooking temperature, the type of illness caused by the bacteria and viruses, etc. We even had a lab where we’d extract bacteria from packaged food, culture it on petri dishes, and marvel at the terrifying things growing in our Cheetos. I’ve never been more thankful for my immune system. Some of that stuff was nasty.

In our lab, one of the ways we would sterilize our equipment is through heat. We’d boil glassware and sterilize our innoculation loops by passing them through flames. But when it came to handling dangerous bacteria, the way we sterilized our samples after we used them was with a microwave.

How microwaves work:

A microwave heats up food through friction. When the microwaves strike food molecules, they “energize” them and cause them to vibrate — it reminds me of the wired feeling that comes after drinking too much coffee. When these molecules start vibrating, they all do so randomly and in different directions, causing them to rub up against each other. This causes heat to be produced where the motion is taking place, and the food heats up in pockets of vibratory friction throughout the food.

However, the microwaves we used in our microbiology lab weren’t helpful because of the heat that was produced but rather because of that vibratory motion itself. Bacteria are teeny-tiny, single-celled organisms with just a thin membrane surrounding all of their important life structures. When they’re placed in a microwave, that membrane starts to vibrate — so much that it sort of “pops” open. Without an intact membrane, the cell dies. When the bacterial cells die, the sample is sterilized.

The same thing happens in our food. When we put something in the microwave, many of the bacteria undergo the same fate as my collegiate microbiology samples — they vibrate to death. The same thing happens with active enzymes in our food that help with digestion and health — the vibration causes them to change shape and die off.

While I know that I eat enough fresh food to keep my microbiome happy, it’s interesting to think that a microwave kind of kills my food. Even after we cook meat or broccoli on the stove, the enzymes in those ingredients are still very much alive because they’re not as sensitive to heat as they are to microwave vibration.

Yes, I still use a microwave regularly, especially to reheat my lunches during the week. It’s part of my regular daily life. But it certainly sparks my curiosity about the necessity of a quick zap compared to tastier, more vibrant, more alive food when I take the time to use some old fashioned heat when I’m at home.

What are your thoughts? Do you use a microwave?