Homeostasis refers to the maintenance of a stable internal temperature and environment that enables the systems in the body, specifically, metabolism, to work to maximum efficiency. Metabolism is the amount of energy the body extracts, stores and uses to maintain itself. The relationship between homeostasis and metabolism is such that homeostasis is required for metabolism to work efficiently and effective metabolism is one way the body maintains homeostasis.
The connection between homeostasis and metabolism is a close one in that should there be a disruption in homeostasis, metabolism will be negatively affected. Metabolism depends on the work of enzymes to catalyze the chemical reactions necessary for the breakdown of food into energy. Enzymes cannot work unless the body is kept at a consistent temperature. Homeostasis must be maintained within the cells for the reactions required by metabolism to take place. Should the temperature be too high, then the enzymes will stop working; should it be too low, then the rate of reaction increases, which may be just as detrimental.
Optimal metabolic efficiency is maintained by the negative feedback loop by which homeostasis operates. Should the sensors in the body detect that a variable such as temperature or pH level is outside the narrow range of acceptability, it alerts controllers such as the hypothalamus in the brain or one of the other body organs to alert the effectors such as blood vessels, the skin or hormones into action. In this way, the relationship between homeostasis and metabolism is stabilized.
Internal conditions of the body that must remain stable include the body temperature, pH level and glucose level. These factors are maintained in a normal range unless there is a build up of toxins; in which case homeostasis and metabolism are disrupted and illness results. Maintenance of a stable temperature is managed by antagonistic mechanisms which include effectors such as the smooth muscles in the arterioles of the skin or sweat glands whose role is to increase the body temperature if external conditions are cold or the body needs to fight off a virus and others that lower it when the sun comes out or the virus is defeated by the immune system. Regulators lower and increase the pH level and hormones reduce and increase the glucose in the blood according to need.