Links
SEGUICI SUI SOCIAL

Science and Concept

Diet and Genome interact.

Nutrition has the most important environmental impact
for life on human health.

What is nutrigenetics:

Nutrigenetics is that particular genetics specialization which aims to examine  how much the genetic predisposition of an individual can  influence its state of health according to the type of diet and  its nutritional requirements. Therefore ,  it studies the impact that the individual genetic profile (genotype) has on the functioning of the whole metabolic process from the carrier proteins, to the enzymes, to  the absorption and  to the problems related to the transport or accumulation of  food. In practice each of us has a different tolerance and predisposition  towards  food and this is all “written” in the genetic code.

Nutrigenetics has also been described as the influence of genetic variation on  nutrition, correlating individual gene expression with the absorption, metabolism, elimination or biological effects of a nutrient. In this way we aim to improve the rational means to optimize the nutrition compared to the genotype of the subject.

In fact, we know that, due to natural mutations, humans differ in their DNA, which is called DNA variation or polymorphism. The most common type of DNA polymorphism is SNP (short for “single-nucleotide polymorphism”). SNP can influence how individuals absorb, transport, accumulate or metabolize nutrients. This can determine the  requirements for the different nutrients and this hypothesis constitutes the basis for the research of Nutrigenetics. Moreover, the different metabolic potential of the human body may imply an advantage in terms of natural selection. For example, it is known that the ability to digest lactose, the main milk sugar, even in adulthood, has spread from dairy livestock breeders.

The identification of the genotype is performed by means of a DNA analysis (blood or oral swab). Subsequently, DNA is analyzed in several ways such as PCR, the Sanger method, Microarrays but today, for speed and completeness, we prefer the so-called “Next Generation” (Next Generation Sequencing) scientific method that leads  to the identification of a complete number of genetic variants. In particular, nutrigenetic analyses are based on the effect of nutritional components on the genome, proteome, metabolome and transcriptome.

One of the main objectives is to identify the genes that make some individuals more susceptible to obesity-related diseases, metabolic syndrome, vitamin defects and genetically transmitted  intolerance reactions.

In the long term, nutrigenetics should allow nutritionists and physicians to identify health and diet recommendations. As a result, preventive medicine, diagnostics and therapies could be optimized.

What is nutrigenomics

On  Nature Reviews Genetics, nutrigenomics is defined as an emerging research field of nutritional science using genome-based data. Some advances in the genetic field such as microarray studies and next  generation sequencing (NGS) are the main genome-based data sources. This type of genomic data collection can be applied to visualize the effects that certain nutrients or foods may have on large portions or different localizations of the genome rather than on a specific location of the genomes.

Nutrigenomics is also defined as a field that examines “the effect of nutrients on the genome, proteome, metabolome, and explains the relationship between these specific nutrients and dietary regimes on human health.”

In other words, a nutrigenomic approach  is a holistic approach  that examines the effect of nutrients at all levels, from gene expression  to metabolic pathways.

Nutrigenomics should not be confused with nutrigenetics, it is a branch of nutritional genomics and is the study of the effects of food and food constituents on gene expression.

It is exactly the opposite of Nutrigenetics, which, as mentioned, studies the effects of food on our organism based on its own DNA.

What is epigenetics

Epigenetics is the study of changes in gene function that do not involve changes in the DNA sequence. The Greek prefix epi-(ἐπι-“Beyond, outside, around”) in the epigenetics implies features that are “above” or “in addition” to the traditional genetic bases for inheritance. This effects on cellular and physiological phenotypic traits may result from external or environmental factors, or be part of a normal development program. The term also refers to the changes themselves: functionally relevant genome changes that do not imply a change in the nucleotides sequence of one’s DNA. There are mechanisms that produce changes that alter the way genes are expressed without altering the underlying DNA sequence. These epigenetic changes can last through cell divisions for the lifespan of the cell, and may also last for several generations even  if they do not imply changes in the underlying DNA sequence of the organism.

An example of an epigenetic change in eukaryotic biology is the process of cellular differentiation. During morphogenesis, totipotent stem cells become the various pluripotent cell lines of the embryo, which in turn become completely differentiated cells. In other words, like a single fertilized egg – the zygote – continues to divide, the resulting daughter cells change in all the different cell types of an organism, including neurons, muscle cells, epithelium, endothelium of blood vessels, etc., activation of some genes by inhibiting the expression of others.

Nutrigenetics and Personalized Nutrition

While Nutrigenetics deals with the way in which the genetic trait of a person  predisposes to food susceptibility, nutrigenomic  asks how nutrition influences the expression of the genome. Understanding the interaction between food components and diet with cells, organs and the whole body are a prerequisite for the biology of nutritional systems.

Personalized  nutrition is a conceptual analogue to personalized medicine. Although food products are available that meet the requirements or preferences of specific consumer groups, these products are based on consumer empirical science rather than nutrigenomics and nutrigenetics.

When dieticians and nutritionists, while using very elaborate systems in the evaluation of caloric, protein and lipid content, of food, prescribe food  regimes without performing a rational nutrient test, they are actually Extremely empirical because they do not take into account the metabolic attitude determined by the genetic substrate of the individual.

Dieticians and nutritionists traditionally base all their diets on the “phenotype”: weight, height, ideal weight, generic body composition. In practice they use empirical methods. Non-Scientific.

Nutrigenomics and especially nutrigenetics are the scientific basis for understanding human variability in preferences, requirements and  responses to a diet and can become the necessary tools for evaluating consumers motivated by Personalized nutritional advice for the maintenance of health and disease prevention.

Traditionally, nutritional research has been involved  in providing nutrients to nourish populations. Nowadays, it focuses on  improving people’s health through diet. Modern molecular nutritional research aims at promoting health, disease  prevention and performance improvement. Personalized nutrition is the concept of adapting food to individual needs. It has become apparent that consumers respond differently to the diet, even  if indicated by a specialist! However, there is a growing awareness on the part of consumers of understanding and evaluating individual health and  nutritional needs.

Responding to this changing landscape of consumers, the nutrition  industry is developing products according to the desired needs and benefits of specific consumer groups, be they healthy, at risk or sick, as sports individuals, seniors, diabetic, obese or allergic.

Although nutrition has traditionally been considered an integral part of maintaining health and disease prevention, it has been based on epidemiological investigations. The task is now to bring the personalized  nutrition to the scientific level.

The personalization of food, as such, is not a new concept, but has been practiced for centuries. However, the emerging scientific basis and  industrialization of  personalized  nutrition and food are new phenomena. The choices of human food have always been  rooted in personal preferences and individual experiences, including sensory acuity, cultural habits and personal economic situation. The nutritional community has acknowledged  that several physiological events require significant adaptations to the diet. For example, pregnant women, active athletes and the elderly have specific nutritional requirements and such needs should guide dietary recommendations.

Today foods on the market allow a substantial personalization of diets based on consumer knowledge and product marketing. This segmentation today is increasingly regulated by the knowledge of our individual genetic characteristics.