Most of our fellow citizens think that health means the absence of illness.

“I am not sick, therefore I am in good health”: nothing could be further from the truth! All chronic illnesses take years to become detectable, and our genes, our potential weight problems, our nutritional habits, our physical, mental and emotional condition will positively or negatively influence the evolution of these silent problems. In 1946, the World Health Organization (WHO) was already introducing a positive (holistic) dimension to the definition of health: “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity”.

There still remained one last step in defining health, however: how do we quantify it? What specific criteria could enable us to say: “I am in good health”, “I am in very good health “or “I am in perfect health”. To define these criteria, scientists tackled this question in a new way: they studied the way in which our organism reacted when subjected to a change, constraint or stress. In particular, they took note of its capacity for resilience. They called this homeostasis.

“Homeostasis is defined as the organism’s capacity to maintain the relative stability of the different components of its internal environment, and this despite constant environmental changes.”

This is its scientific definition. But to properly understand this fundamental phenomenon, we’ll have to put our imagination to work: suppose we are all born… on a steel wire stretched between two towers; our parents and their parents are all accomplished tightrope walkers and live permanently, twenty-four hours a day, on this wire. In order not to fall we will constantly need to acquire a dynamic balance which will require the involvement of hundreds of our muscles, our organs, our senses, our brain which will evaluate our strategic choices, our emotions which will have to be managed when danger lurks, and this… twenty-four hours a day, relentlessly. Not one second of relaxation! That is homeostasis!

Homeostasis is therefore not static, it is a constant search for equilibrium between activating and inhibiting forces. These variations should not exceed certain limits, however, beyond which cell survival is jeopardized. Homeostasis is stabilized when cellular needs are met. Yet the fulfillment of these needs is ensured by the synergistic work of all cells and therefore of tissue, organs, and all of the organism’s systems.

Even if we cannot perceive it externally, our body’s internal environment is the seat of countless and continuous changes which cause imbalances. And so, just as it is for the tightrope walker balancing himself on a wire, cells must react in order to adequately compensate these imbalances. So long as cells accomplish all of the needed compensatory actions, the organism remains in dynamic equilibrium, or homeostasis. If cells are not able to quickly restore internal balance by carrying out the appropriate compensatory actions, a major imbalance, called “illness”, is unavoidable, just as f.a fall would be inevitable for the tightrope walker if he hesitated in the movements to recover his equilibrium.

The system’s reorganization must be constant, mirroring its disorganization. All of this supposes precise mechanisms which take part in maintaining balance: this is called regulation. “Regulation comprises all of the mechanisms ensuring the constancy of a chemical or physical characteristic of the internal environment”. This is accomplished by error-correction systems. The correction mechanisms must be immediate and adequate: they process information through different receptors and work either by up- or down-regulating, or sometimes amplifying upward or downward trends when this proves to be necessary for our health.


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