What is Homeostasis?
Updated: Sep 20
You must have heard this sentence before: “the human body is a perfect machine”. But did you ever stop to think about what guarantees our perfect functioning considering how complexly we are built? When we feel goosebumps on our skin from the cold or when we sweat after practicing physical activities, these are physiological responses whose goal is to keep our body’s internal temperature in balance. It is through this matter that we can touch on the subject of homeostasis, which acts on maintaining the balance of our body’s functioning.
What is homeostasis?
The human body needs to be in balance in order to guarantee its functioning.
In an interview to UOL, Nicolle Queiroz, a cardiologist and professor of the Medical School of the Universidade de Santo Amaro (Unisa), in Brazil, explains that sweat, for example, is part of a mechanism called homeostasis, which is responsible for regulating body temperature so that all body functions happen seamlessly.
Professor Kelvin S. Rodolfo from the University of Illinois starts an interview with Scientific American by explaining what homeostasis is according to the word’s meaning. “Homeostasis, from the Greek words for "same" and "steady," refers to any process that living things use to actively maintain fairly stable conditions necessary for survival”.
The term was coined in 1930 by the physician Walter Cannon. His book, The Wisdom of the Body, describes how the human body maintains steady levels of temperature and other vital conditions such as the water, salt, sugar, protein, fat, calcium and oxygen contents of the blood. Similar processes dynamically maintain steady-state conditions in the Earth's environment.”
“All vital mechanisms, despite their diversity, have only one function: to keep the life conditions of an internal environment constant.”
Ismar states that we must understand homeostasis as an organism’s tendency to maintain its internal conditions always within normal or physiological parameters. According to their position on the evolutionary scale, living beings may present a bigger or smaller ability to adapt to their environment.
“Each moment in which there is a tendency to imbalance, the homeostatic mechanisms will show up in order to ensure regulation or the return to normality. This applies, among others, to the regulation of the body’s pH as well as to thermoregulation and circulation,” he writes.
What is the importance of homeostasis?
Homeostasis acts mainly in the functioning of the nervous and endocrine systems. The nervous system coordinates bodily functions and the endocrine system indicates “what must be done” for each organ.
If a system is under conditions that provoke alterations, it then faces instabilities – and its tendency is to act in order to combat such alterations. Homeostasis has a fundamental role in this process.
Professor Kelvin S. Rodolfo also mentions the importance of the human body’s temperature control processes. “For example, the human body uses a number of processes to control its temperature, keeping it close to an average value or norm of 98.6 degrees Fahrenheit. One of the most obvious physical responses to overheating is sweating, which cools the body by making more moisture on the skin available for evaporation. On the other hand, the body reduces heat-loss in cold surroundings by sweating less and reducing blood circulation to the skin. Thus, any change that either raises or lowers the normal temperature automatically triggers a counteracting, opposite or negative feedback . Here, negative merely means opposite, not bad; in fact, it operates for our well being in this example. ”
He emphasizes that “homeostatic reactions are inevitable and automatic if the system is functioning properly, and that a steady state or homeostasis may be maintained by many systems operating together. For example, flushing is another of the body's automatic responses to heating: the skin reddens because its small blood vessels automatically expand to bring more heated blood close to the surface where it can cool. Shivering is another response to chilling: the involuntary movements burn body tissue to produce more body heat.”
Kelvin S. Rodolfo explains furthermore that oscillation is a common and necessary behavior of many systems and that they themselves promote such oscillations above and below the equilibrium level.
Homeostatic systems evolved throughout the years to help the body maintain its ideal functions in different environments and situations. But beyond that, according to an article published in 2013 by the National Library of Medicine (National Center for Biotechnology Information), a group of scientists theorized that homeostasis mainly provides a “quiet background” for cells, tissues and organs to communicate with one another. The theory proposes that homeostasis makes it easier for organisms to extract important information from the environment and to transmit it between different parts of the body.
Homeostasis beyond physiology
Moving slightly away from the explanations of homeostasis in the body, professor Kelvin S. Rodolfo says that homeostasis has also found useful applications in the social sciences. “It refers to how a person under conflicting stresses and motivations can maintain a stable psychological condition. A society homeostatically maintains its stability despite competing political, economic and cultural factors. A good example is the law of supply and demand, whereby the interaction of supply and demand keeps market prices reasonably stable.”
Written by Débora Nazário
Translated by Mariana Gruber
The body needs to return to homeostasis when it encounters a stress factor. When we think about this stress factor, we usually think of a flu that weakens our bodies or makes it feverish in order to combat an infection; or we think of a freezing-cold day and clothes that are not warm enough, thus our bodies shiver uncontrollably in order to generate heat and avoid lowering its temperature.
However, there’s also psychological stress: when we are overloaded or concerned about something. Our bodies have a series of responses in the face of stress and each person reacts differently. Some people sleep, others crave sweets; some lose all appetite, others feel constipated – or need to visit the toilet five times a day. All of this is our body showing us that there is an imbalance that may be emotional.
Kids can also be stressed and have responses such as a lack of appetite, sleep deregulation or irritability. You need to stay alert and seek the help of pediatricians and therapists in case one of these warning signs is identified.
Truth and Tales, our children’s well-being app, relies on some activities that may help kids return to their homeostatic state. The interactive stories and audiobooks are Teaching Stories, ancient stories structured in a way that improves neuroplasticity and provides space to develop finer skills, such as focus and attention.
We also offer physical activities that integrate the body and mind and help restore homeostasis. In a playful and fun way, kids are given space to notice their bodies and their feelings, placing their attention back on themselves.