The normal temperature of a human body is 36.8 degree Celsius or 98.6 degree Fahrenheit. When the body suffers from fever, the normal temperature rises causing the body to get warmer.But surprisingly while the body gets hot during fever, we feel cold and gets shivering sensations. Have you ever thought what is the reason behind this bizarre phenomenon of human body. Lets find out why this happens.
The human brain controls and regulates the body temperature. The part of the brain called hypothalamus acts as the internal thermostat which examines when to increase or decrease the body temperature. It has a set temperature point which is the normal body temperature. When the body suffers from fever, the immune system inside the body changes this set temperature point and pushes it higher. As soon as the temperature is raised, the brain thinks that now the body is cooler and its temperature needs to be raised to match the new set point. We get the shivering sensation as this the way body tries to raise it’s temperature through muscle work (contraction and relaxation)and get it up to the new set point.
When the fever lowers, we do get sweat. This is also due to the internal thermostat. When it realizes that the body temperature has risen above the set temperature point, it tries to lower the body temperature via sweat. So its the human brain that governs even the body temperature.
One of the most interesting fact about fever is that it’s a way the human body fights against any infections. The theory behind this that the bacteria have the most growth at normal body temperature. So whenever there is any infection the human brain raise the temperature of the body which slows down the production of bacteria and increases the production of white blood cells hence prevents the infection to grow rapidly.