Body temperature -Things you need to know about your body temperature

Temperature is commonly defined as the degree of hotness or coldness of a body; in other words, it is how cold or how hot a body is at a particular time.
Living things are classified into two based on how their bodies regulate temperature:

• Poikilothermic organisms
• Homeothermic organisms

In poikilothermic animals, the body temperature is largely dependent on the temperature of the surrounding environment and these animals are said to be cold-blooded.

In homeothermic animals, however, the body temperature does not really depend on that of the environment though may be affected in one way or the other. Homeotherms are called warm-blooded animals and they have the ability to keep their body temperatures within a constant range.

Human beings are warm-blooded animals, hence have a constant body temperature with little variances; being lowest in the morning and highest in the evenings. The body temperature is very important in determining the metabolic activities going on in the body.

How is body temperature measured?

An instrument known as the thermometer is used to determine the temperature of a body. It is commonly placed in the armpit, but may also be placed in the mouth (under the tongue), rectum, or over the skin.

What are the normal temperature values?

The normal body temperature is about 37.5°C; there may be differences based on what part of the body is used to access this value.

What can cause changes and differences in body temperature?

• Gender
  Body temperature is higher in males and lowers in females; this is because females have a lower basal metabolic rate as compared to males.
  During menstruation as well, body temperature tends to fall a little in females adding to this difference.
• Age
  When a child is born, the temperature regulating areas in the hypothalamus are not yet fully developed, therefore children have fluctuating body temperatures which will depend on how hot or cold their surrounding environment is. The temperature of children is about 0.5°C higher than that of adults.
  In old age, heat production becomes less causing a very slight decrease in body temperature.
• Sleep
  Whenever we sleep, our bodies are at rest as compared to when we are awake; this causes the body temperature to fall slightly.
• Exercise
  Exercising is a way of producing heat in the body; this is why we sweat after every exercise. As a result of this heat that is produced, the body temperature rises for a brief moment and then normalizes after the exercise.
• Emotion and mood
  In emotional conditions like crying, the body temperature increases slightly.

How does the body regulate its temperature?

It is important to regulate body temperature because biochemical reactions in the body can only occur under certain conditions of core body temperature. The enzymes that catalyze the reactions necessary for our body’s survival will fail to function and be denatured at either very low or very high temperatures.

When the environment is cold, mechanisms are put in place to prevent our body temperature from falling below normal; therefore the body tries to generate heat by either of the following:

• Shivering
  Shivering causes rapid contraction of muscles (similar to when we perform exercises) which produces more heat for the body and helps to keep it warm.
• Hairs
  In very hairy animals, during the cold weather, their hairs serve as insulators. Hairs on the skin will be seen to stand in order to trap heat and keep the body warm.
• The body also sends information that tells us we need to put on a sweater that will act as an insulator; goosebumps are a common sign of this.
• Additionally, the body tries to prevent excessive loss of heat by constricting the blood vessels present on the skin.

When the environmental temperature is increased, the body tries to lose excess heat by some of the following mechanisms:

• Sweating
  One of the major ways our bodies respond to a hot environment is by the secretion of sweat. Not only does this help the body in losing heat, but it also enables the skin to be cooled as the sweat evaporates.
• The blood vessels of the skin become dilated to also help reduce the temperature.
• Additionally, the brain inhibits activities that produce heat like shivering.

Hypothermia and Hyperthermia

When the body temperature falls below 37°C, it is referred to as hypothermia, and when it rises above 37.8°C, it is referred to as hyperthermia.

Therefore, hypothermia is an abnormal decrease in body temperature, while hyperthermia represents an abnormal decrease; the effects of both being very dangerous to the body.