Q. Why do you shiver when you get cold?

A. People shiver automatically when they get cold. The body has nerve cells that are sensitive to hot and cold and act as a thermostat. These nerve cells are sensitive to hot and cold and act as a thermostat. These nerve cells are found in the part of the brain called the hypothalamus, which is about the size of a cherry. When you get cold, these cells trigger a message that makes you start to shiver. The muscles in your body tighten up, and this helps produce heat. Shivering when you have a fever is caused by a substance in the white blood cells. When this chemical is released into the body, it changes the thermostat, forcing the body to get rid of heat.