That's Not How Any of This Works!

Microwave ovens cook from the inside out.

Pretty neat, right? Only it’s completely wrong. In fact, a device called a magnetron uses a very strong magnet to induce electromagnetic waves (a form of light).

These waves bounce back and forth inside the microwave, bouncing off of the metal, ultimately penetrating the food that’s in there. This causes the molecules in the food to vibrate, creating friction. Friction causes heat, and that’s what cooks your food.

In fact, microwaves are more likely to heat something from the outside in, especially if the thing is thicker. Those waves (made up of photons) lose momentum as they enter a substrate, so the outside heats up faster.

I wrote an origin story of sorts, about when this phenomenon was first explored:

How could I have grown up believing I understood this phenomenon, only to find out it’s all nonsense?

Maybe more importantly, what other things are like this? It turns out that there are quite a few.

Has anyone ever warned you to stop cracking your knuckles, lest you end up with arthritis? I know I was told this many times growing up, and while this may have frightened me a bit, it did not deter me from cracking my knuckles compulsively.

It’s a good thing it’s not true! When you hear that pop or crack, you’re listening to a gas bubble or pocket breaking up, kind of like when you squeeze or twist bubble wrap.

Your joints are filled with synovial fluid—a lubricant that helps facilitate joint bending. This fluid fills up with little gas bubbles whenever you extend the joint. When you pop a knuckle, you’re popping one of those bubbles.

Like the microwave inside-out myth, this one turns out to be the exact opposite of what we once believed: careful joint cracking may actually have some minor health benefits, and it certainly does not cause arthritis.

Incidentally, jiu jitsu certainly does cause arthritis! Here’s me doing a BJJ move where you can see my gnarled hands just a bit:

There’s one more health-related myth I heard growing up: that chocolate causes acne. This one was pervasive, and virtually every teenager I knew believed it to be true.

In fact, dark chocolate—the real stuff—is starting to be thought of as a bit of a superfood. It contains antioxidants with anti-inflammatory properties, helping to remove free radicals and improve blood flow to the skin.

Now, I’m not here to tell you that eating a ton of crap food isn’t going to make your skin break out, but I am here to tell you that it’s not the chocolate that’s going to do this.

Incidentally, I was given the opportunity to work on a comprehensive piece about chocolate with two other folks, both excellent writers:

Michael Woudenberg

, which whom I’ve done several other works, and

Birgitte Rasine

, who is deeply involved in the world of all things chocolate:

Ode to Chocolate

Debunking can be fun, but it’s noteworthy to consider how many of these pervasive little myths made their way into my worldview, and how many of them turned out to be the opposite of what we thought.

It always gives me pause to reconsider what sorts of myths are still pervading our lives today. The drunken octopus phenomenon offers me a lot of comfort, since there’s pretty much nothing we can’t look up nowadays… but even still, are there things pretty much everyone takes for granted, and virtually nobody bothers to even try to debunk?

Yeah, probably. What are those things? I’ll probably have to get back to you in a few decades.