For the proper functioning of our body, every parameter must be perfect. Although our bodies are a culmination of various complex systems, an organism (a pathogen, to be precise) can evade the body and cause disease, thus proving the fragility of the human body. Yet, while the body does manage to defend itself, it takes a while to return to its normal state – the normal state referred to here is called HOMEOSTASIS.
The textbook definition of homeostasis is a state of the body wherein there is a steady internal, physical and chemical condition maintained. Homeostasis is a broad term used about various variables in the body, such as the blood pH, the levels of nutrients such as iron or zinc or most commonly, the body temperature.
Homeostasis of the body is maintained via two routes, i.e. NERVOUS SYSTEM and the ENDOCRINE SYSTEM. The nervous system consists of the CENTRAL NERVOUS SYSTEM (CNS) and AUTONOMIC NERVOUS SYSTEM (ANS). The endocrine system is responsible for the secretion of hormones, which plays a role in maintaining homeostasis in conjugation with the nervous system.
The homeostasis of maintaining body temperature is called THERMOREGULATION. It is because of thermoregulation that the body can maintain its internal core temperature – an example of EQUILIBRIUM. Our regular body temperature is within the range of 98°F (37°C) to 100°F (37.8°C). Any variation in this temperature may be an indication of a malfunction in the form of the disease.
Many of the biomolecules in our body, such as ENZYMES, require a specific temperature to function optimally – this is usually 37°C. A deviation from this can cause the activity of the enzymes to drop. So, it is very crucial to maintain the temperature within the normal range. Falling of the body temperature to drastically lower than the 37°C leads to a condition called HYPOTHERMIA, causing the heart to go into cardiac arrest or can lead to brain damage.
External factors such as the activity one are engaged in and weather can change the internal core temperate – while some activities such as exercise can increase the body temperature, agents such as alcohol can lower it. The HYPOTHALAMUS is in charge of making a split-second decision about what to do to bring the temperature to the optimum.
How does the body lower the body temperature?
Contrary to popular misconceptions, fever is not a wicked thing – it is a defense mechanism. In the case of the invasion of a pathogen, the hypothalamus decides to increase the body temperature (within the tolerance of our cells) to make the body unsuitable for the bacteria. Like human enzymes, bacterial enzymes also require a certain temperature to function – since the temperature of the host is increased, the said bacteria enzymes are inactivated and the spread of the disease is slowed down.
In such a condition, as the body is secure from the infectious agent, it is necessary to bring the body back to homeostasis. It is commonly experienced that fever is often followed by profuse SWEATING; this is the mechanism by which heat is lost from the body and homeostasis is restored. As sweat glands release sweat, its evaporation causes cooling of the skin.
Secondly, the internal temperature is lowered by the process of VASODILATION. Vasodilation is the process by which the blood vessels get wider and allow more blood to flow. This allows blood to flow from the warmer parts of the body to the cooler ones, thus lowering the overall temperature.
What happens in case of low body temperature?
Low body temperatures can be encountered especially in a cold climate – the condition of the body where its temperature is lower than the ambient is called hypothermia. To reverse this, the hypothalamus has ways to increase body temperature.
A common experience during cold weather is that of shivering – which refers to trembling. This is facilitated by muscles to bring heat to the body. The process of generating heat by the various organs of the body is called THERMOGENESIS. Above mentioned was the process of vasodilation. The complimentarily opposite process of vasodilation is that of VASOCONSTRICTION – the narrowing of blood vessels to restrict the flow of blood, thereby warming the surrounding area.
Lastly, hormones such as the THYROXINE (the hormone secreted by the thyroid gland) can aid in thermogenesis and restore the temperature of the body.
To sum up, the body has a load of processes to maintain the optimal function of the body. It is still one’s responsibility to not put the body in such a situation. For example, carrying appropriate clothing in the form of sweaters and jackets while going to a cold place will immensely reduce the chances of hypothermia in the individual. Also, consuming healthy food which can bump up the immune system and maintain the homeostasis is a wise step.