Why do our teeth chatter when we're cold?

HI there,

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, to create heat. This is the same reaction when your legs start to quiver, or your abdominal muscles begin to quiver. This is the body's natural mechanism to create heat (as the muscles quiver this creates friction inbetween the muscle cells, thus causing heat).

Hope this helps,

Kelly McBride, RDMS

You know, I've always wondered that. Perhaps that's a reflex to pump up energy and heat to keep the area around our brain warm.
to try to warm up ur body like when you start rubbing ur arms up with ur hands. its also a signal from our brain.
Your body is trying to generate heat by shivering.
Due to the muscles constriction that produce energy/warm and prevents freezing.
Because when the body temperature drops below normal the heart pumps blood faster through your body as a defence mechanism. This causes your teeth to chatter due to the blood pulsating around your facial area .