Already in the ancient times people attached a lot of weight to variability and difference as these phenomena are connected mainly with susceptibility to diseases.
At present, despite modern research techniques and advanced works on the human genome and genotype, the attempts to gather available data on variability have not given the expected results.
Such a study is difficult, probably due to great variability of available data. However, based on this data it may be stated that variability has a greater importance in biological sciences and in medicine than is usually thought.
From the standpoint of sciences applied in medicine, people may be divided into two groups.
The first one, which contains most people, consists of individuals with properties within what is recognized as normal range. The second group includes a definite minority; the properties of these individuals differ from the norms to such an extent that these individuals can be considered “abnormal” themselves.
The most common criterion of distinguishing normal individuals from abnormal ones in biology is 95% credibility. This means that all properties which are different from those possessed by 95% of the population can be recognized as deviations and individuals with such properties are not normal.
A human has a great number of all measurable properties. If there is no mathematical relationships between many of these properties, we come up against a concept which is contrary to the division of people into normal and abnormal. If 0.95 of population includes normal individuals in terms of only one measurable property, the calculations will result with the number of 0.902, i.e. 0.952, for two such properties and the number of 0.60, i.e. 0.9510, for ten such properties. In the event of a hundred non-correlated properties, it would turn out that only 0.0095 (0.95100) of population is normal.
Humans have a great number of measurable properties and probably not always is there a mathematical relationship between them. This fact speaks in favour of the hypothesis saying that each person has a deviation of a kind.
In most cases, such „abnormalities” are hidden. Although they can often be related to susceptibility to diseases in the older age, they are usually not detected during clinical tests.
Why do scientists generalize?
One of the factors which encouraged scientists dealing with biology and related sciences to somehow ignore the issue of deviations is the tendency to generalize. Generalizations form the foundation of each science. Science cannot exist without generalizations.
From the viewpoint of biology, justified generalizations which include all humans, all mammals, or all representatives of any group of living creatures, seems very desirable.
At present, in the sciences concerning a human and related directly to medicine, there is a tendency to focus on a “normal human”, i.e. a creature who generalizations are made for. Each scientific study in physiology, biochemistry, pharmacology, or psychophysiology is mainly related to an average human and reactions of his body.
The importance of variability is most often omitted and no special weight is attached to it. However, the thesis that “each person has a deviation” can explain the issue of susceptibility to diseases.
What are the conclusions of genetic research?
The developments of biochemical genetics have proved that heredity and related mutations result not only in the existence of basic interspecies metabolic differences but also in other minor differences within one species.
However, we should not forget here that genes and enzymes originating from them are not able to produce chemical metabolites from nothing and that the course of many complex metabolic processes depends on the inflow of appropriate materials. That is why diet is so important and cannot be omitted in combination with hereditary factors.
Heredity determines possibilities of organisms consisting in conducting complex chemical processes on condition of the inflow of necessary materials obtained from food. Current achievements of nutrition sciences indicate that the causes of idiopathic diseases in people are completely unknown. The supposition that nutritional deficiencies resulting from specific hereditary needs play a role here has not been taken into account so far.
Genetotrophy, that is nutritional variability
Heredity and genetic difference in nutritional requirements form the grounds for genetotrophic theories.
Genetotrophy emphasizes vast possibilities of nutrition in levelling exceptional nutritional requirements which are conditioned genetically.
The principle of genetotrophy says that each body with a specific genetic make-up has specific nutritional needs; the satisfaction of these needs is a condition for the optimum biological success. This principle gives us certainty that a diet taking individual genetic deviations into account makes it possible to solve many bothersome health issues.
However, in order for a person to satisfy these individual requirements, such requirements must first be identified. They may not be explored without determining differences between separate individuals.
If the principle of genetotrophy is so important as results from current materials, it should be supposed that in the nearest future the nutrition science will more and more focus on examining and satisfying individual needs which are not, admittedly, typical of the whole human race in terms of quantity, but are more or less characteristic of and decisive for individual people.
Deviations as a biochemical property of patients' individuality
Therefore, learning about biochemical individuality forms a basis for solving issues which biochemical variations play a role in.
When considering various fields of biochemistry, the number of these issues and their relationships with occurring deviations become more and more obvious. In biology and medicine, such as in social and philosophical sciences, too much attention has been paid to creating a model of the “one and only human”.
On the other hand, too little weight has been attached to individuals forming the species and society, i.e. people who become patients. We should get to know people and patients and understand them as they are.
In our opinion, this may be easier owing to knowledge of variability and individual differences.