Regardless of the time or season, your body maintains a fairly constant body temperature of about 98.6°F or 37°C. Even internally, there are various processes occurring and generating heat, but the body stays at the right temperature. Minor variations in the body’s temperature occur during daily activities such as exercise and sleep. Larger variations, however, may be a cause for concern. Even just a few degrees on either side of the normal mark can indicate that something is amiss in the body and its surroundings. The human brain has a way of regulating the temperature in the body, so when the temperature is too high or too low, this could indicate a few different causes.
The Hypothalamus and Temperature Regulation
The brain is divided into specialized regions. Each of these parts is responsible for controlling or regulating certain body functions. The hypothalamus is a small part of the brain, which controls various functions and processes, including the nervous system’s coordination and the body’s temperature regulation. It is also responsible for controlling the release of important hormones and balancing the fluid and salt concentrations in the body.
As far as temperature control, the hypothalamus is constantly checking what temperature the body is at. When the temperature is too high, the hypothalamus makes sure that the body gives off some heat. Sweating is one way to do this because the evaporation of water droplets from the skin requires heat and therefore has a cooling effect on the body. When the body’s temperature is lower than normal, the hypothalamus causes the body to generate more heat and to retain more of it as well.
The body’s heat-regulating system is complex, sophisticated, and automatic. The hypothalamus functions as the body’s thermostat set at 98.6°F and works with other parts of the body to balance heat generation and heat loss. The skin works together with the sweat glands to release heat. On the other hand, the blood vessels contract and expand depending on what is happening in the body. These actions lead to heat conservation or heat loss, respectively, because the vessels carry warm blood in them. Heat is lost when this blood is brought closer to the skin’s surface during expansion.
Fever in the Body
Fever is characterized by high body temperature and can be a symptom of illness. As the body goes beyond an elevated temperature to temperatures of about 99.6- 100.4°F and above, a person is said to be experiencing a fever. A high fever is for temperatures above 103.1°F, and a very high fever is for body temperatures over 105.8°F.
During a fever, the brain sets the body temperature to a higher level than normal. This is usually as part of the immune system’s efforts to fight off pathogens such as bacteria and viruses. During such an infection, the hypothalamus signals the body to release chemicals that contract the blood vessels. This draws them away from the skin, reducing heat loss, and raising the body’s temperature.
Fever, in general, is just a sign that the body is working to protect itself. It is only when a fever gets into the higher temperatures of above 102°F and persists for a couple of days that it becomes a cause for concern.
Other Causes of Temperature Change
Fever is not the only thing that can raise the body’s temperature. Hyperthermia is an elevated body temperature caused by an imbalance in the amount of heat the body produces and absorbs compared with what it loses. When this is severe, it is referred to as heat stroke. During menopause, women often experience hot flashes due to hormone changes. The other side of the coin, when the body temperature sinks below the normal because of extreme cold, is known as hypothermia.