18 October 2008

Why do our teeth chatter when we're cold?

I've always wondered. So I did some research. Turns out our teeth chatter when we're cold for the same reasons we sweat when we're hot: thermoregulation.

Basically, whenever the brain senses a dramatic change in body temperature it will either signal our muscles to move to generate more heat to warm our body or sweat to cool off in order to maintain homeostasis.

But while we might cup our hands and exhale into them, rub or arms or jump around to generate some warmth, the teeth chattering is involuntary. The teeth chattering is actually due to the muscles of your face contracting to generate heat in order to keep your head warm. So basically our teeth chatter because when the brain realizes you're cold it will send a signal to your muscles to start moving to produce heat. The same way you sweat when you are hot because the body is trying to cool off. The brain - the hypothalamus, to be more specific, monitors your temperature and does what its gotta do to keep you at 98.6

This is the body's natural defense to hypothermia. When your teeth chatter, your teeth aren't the ones that are in control. Your periodontal and masseter muscles are being stimulated by your sympathetic nervous system to quiver or create heat. This is the body's natural mechanism to create heat (as the muscles quiver this creates friction inbetween the muscle cells, thus causing heat).


Anonymous said...

Don't you have something else to do? Get a job or something.

Unknown said...

but even when your not cold
your teeth chatter a little.
Try it now, modify your bit so just your front top teeth touch your front bottom teeth, ever so lightly.

Do they chatter? Why?