So I fell down the stairs last night. It was a fairly spectacular wipeout--they were wet, and I lost my balance--and caused a muscle spasm so bad that I had to call a nearby friend because I was afraid I couldn't walk.

Now I'm on my couch with a brand new heating pad. I call it a "heating pad" only because this is the appellation the manufacturer has chosen; it doesn't actually produce much in the way of heat.

My first instinct is to blame this on the safety nazis. But this seems ignoble; perhaps the damn thing just doesn't work.

Except that, having a bad back, I have noticed a similar trend in other heating apparati. I usually buy ThermaCare patches for travel; the heat keeps my back from spasming. Lately, however, I have noticed that the heat patches no longer produce much in the way of heat. They used to produce a comforting glow that kept my back relaxed for eight hours or more. These days, I could get a better heat level by dipping my napkin in the lukewarm airline tea and slapping it on my back.

This makes me suspect that they have lowered the amount of heat that heating appliances produce, presumably because people with very poor circulation, such as diabetics, were burning themselves. Apparently, it is much better for them, and everyone else, to have something labeled a "heating pad" that doesn't produce any heat. I'm all for exploiting the placebo effect, but it's hard to generate a willing suspension of disbelief while lounging on a stone-cold chunk of plastic.

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