What Is a Body Thermostat?

The human body consists of a complex set of organs, tissues and fluids that work in unison. In order to sustain proper bodily function, the body must maintain a consistent body temperature. A gland located in the brain, the hypothalamus, has the primary function of regulating body temperature. The hypothalamus sends instructions to other organs in the body in the event of abnormalities in body temperature.

Responses to Heat

• Body temperature naturally rises when exposed to great sources of heat such as the sun during the summer, fire or indoor heaters. The hypothalamus learns of changes to body temperature through skin warmth receptors and blood flow. In response, the hypothalamus triggers the release of sweat glands. Sweating is the most effective way the body can lower its internal temperature. The risk of dehydration is increased if the body does not replenish the fluids lost by sweating. Behavioral and voluntary responses to increased body temperature includes lethargy and laying down in a prone position.

Responses to Cold

• Prolonged exposure to cold weather can rapidly decrease skin temperature. Cold thermoreceptors respond by cooling the blood that flows into the skin. The hypothalamus is alerted to this change by the thermoreceptor. The hypothalamus then initiates responses that promote heat gain and prohibit heat loss. Involuntary contraction of skeletal muscles occurs, for example, which creates the shivering motion. Piloerection also occurs, which is the standing up of hair on the skin. Tiny bumps known as goosebumps appear throughout the skin as a result.

Metabolism Response

• Food that is eaten throughout the day is transformed into energy that is used for bodily functions such as growth, tissue regeneration and normal bodily operation during physical activity. Energy that cannot be utilized in these processes is converted into heat. The hypothalamus rejects the majority of the heat in order to maintain the proper body temperature.