In response to infection, the hypothalamus in the brain can induce a temporary increase in body temperature (fever) in a number of ways. （highwaystarz-photography via getty images）
You wake up in the middle of the night shivering. You have a fever, which is a temporary increase in body temperature.
Fever can be caused by the body's defense system fighting infection, but they can also be triggered by other factors, including autoimmune diseases such as rheumatoid arthritis, or as a result of certain medications.
But what happens to the body when you have a fever?
The body temperature varies slightly from day to day and from person to person, but is usually maintained at 98Around 6 degrees Fahrenheit (37 degrees Celsius). This creates the perfect environment for our cells to work efficiently. The part of the brain known as the hypothalamus acts like a thermostat that constantly monitors the body's temperature and turns the internal dial to control it back to about 986 degrees Fahrenheit.
During infection, when our immune cells detect foreign invaders such as bacteria or viruses, they release thermogenic chemicals called pyrogens. These chemicals go into the brain, where they act on temperature-sensitive neurons in the hypothalamus, basically telling it to raise the temperature in the house, says Paul O, an assistant professor of medicine at Johns Hopkins University'Dr. Rourke told Live Science.
As a result, these neurons release hormone-like substances called prostaglandins – specifically a substance called PGE2 – that distort the dial on the body's thermostat and trigger a fever.
When you reach more than 38 degrees Celsius (1004 degrees Fahrenheit) when we usually consider fever, "o."'Rourke said.
The hypothalamus can raise body temperature in a number of ways. For example, it directs blood vessels to constrict, thereby reducing the amount of heat emitted through the surface. It also causes shivering to produce as much heat as possible.
Together, these physiological processes form part of the body's first line of defense against infection, known as acute inflammation. The main purpose is to control the infection and stop its spread.
Paradoxically, even when the body temperature is rising, people may experience chills along with a fever. This is because the hypothalamus temporarily raises the body's internal thermostat to a higher "normal" level. As your body tries to reach this new baseline, you will feel relatively cold.
So, why does the body need calories?
o'One possible reason, Rourke says, is to make it harder for bacteria or viruses to replicate and infect our cells. A higher body temperature may also turn the immune system into a better "fighting machine," he said. For example, when our body temperature rises, cells produce heat shock proteins (HSPs), which activate immune pathways to fight infection. HSP is usually upregulated by cells during inflammation as the body works hard to protect itself from foreign invaders.
For the average older child or adult, you might have a fever for a few days, two or three days of course, without necessarily needing a lot of medical attention," Kitty O, a counseling assistant at Duke University's Department of Medicine'Dr. Hare told Live Science.
But if you're concerned about your symptoms, or if they don't seem to be improving, you should contact your healthcare provider, she says.
For example, sometimes when a child has a high fever, they may experience a convulsion called a febrile seizure. While these can be scary, they usually only last a few minutes and are usually harmless. Still, parents should call their health care provider when their child has a seizure, even during a fever, O'Hare said.
The degree of fever is also important, O'Hare said. "Based on your health history, get advice from your own healthcare provider about how much of a problem a fever is for you," she said.
Depending on your age, over-the-counter medications such as acetaminophen or ibuprofen can help relieve fever symptoms. Removing a layer of clothing, taking a cold shower, and drinking cold water can also help with fever, she said.
It takes a lot of effort to raise your body temperature during a fever – every 1At 8 degrees Fahrenheit [1 degree Celsius], you'll use 10 percent more energy than you would normally use to maintain your body temperature. Therefore, it is important to maintain a good rest, o'Rourke said.
This article is for informational purposes only and does not provide medical advice.