Dietetic

Dietetic : nf Diet is the science of balanced eating. If nutrition is defined as the science that analyzes the relationship between food and health, dietetics includes a cultural dimension linked to eating practices.
Nutrition is the science that studies foods and their effects on humans, while dietetics is the study of the set of rules that should govern the diet of humans.
Diet is a “social norm” which varies according to the times, according to civilizations, according to religions or beliefs and of course according to the state of knowledge in nutrition.
In our time, under the effect of scientific development, the two concepts tend to come together. The “dietary standard” is based on ever-increasing scientific knowledge.
The objective of dietetics is to enable human beings to maintain or regain their weight, and to preserve or improve their health.
To stop certain distortions of competition between companies and the frequent confusion made with normal foods bearing nutritional or health claims1 or intended for specific people (allergic, etc.), the European Parliament decided on 11 June 2013 to eliminate the official vocabulary the expression "dietetic foods"
Dietetics studies the nutritional value of consumer products, identifies diseases caused by poor nutrition and calculates food rations suitable for various categories of consumers. This science focuses not only on the practice of diets, but also on the psychological, even sociological, aspects of food. In addition, proper culinary issues are not foreign to it, insofar as the quality of food and the way it is prepared and cooked affects its food value. For special diets (in the event of heart disease, diabetes, obesity, etc.), we speak more of “diet therapy”.

Traditional Dietetics: The history of the evolution of dietetics shows that there is not dietetics but dietetics, which depend on the conception of digestion and knowledge of food.
Until the development of chemistry, ancient dietetics in Europe, India and China had great common points:
- digestion is a cooking of food;
- the body is made up of elements which determine a temperament;
- it is recommended to eat balanced food, that is to say foods corresponding to his temperament.
For Hippocratic dietetics, there are 4 elements: water, earth, air, fire, which correspond to 4 temperaments: lymphatic, melancholic, bloody and angry. Each food is classified into hot, cold, dry or wet.
For Ayurvedic dietetics, there are 5 elements: ether, air, water, fire, earth, which correspond to 3 temperaments: vata, pitta, kapha. Each food is classified according to the elements, temperaments or doshas, ​​6 flavors and 3 categories or gunas (sattvic, rajasic or tamasic).
For Chinese dietetics, there are 5 elements: wood, fire, earth, metal, water, which correspond to the same 5 temperaments. Foods are classified by flavor, color, consistency. Food can also be yin or yang.
Hippocratic dietetics and Chinese dietetics have survived advances in medicine and chemistry, while Ayurvedic dietetics only survive in India (Unani-Tibbi medicine). Naturopathy has taken over certain concepts of medicine ayurvedic.

Scientific dietetics: Scientific dietetics in the West have changed its definition of digestion: all the mechanical and biochemical processes ensuring the transformation and absorption of food. It changed the classification of foods, now composed of nutrients, directly assimilated: proteins, lipids, carbohydrates, vitamins, minerals, trace elements.
Official dietetics still maintain the concept of balanced food to maintain health.
Alternative dietetics: Protesters of official dietetics created, in the twentieth century, several alternative dietetics, which take up both theories of ancient dietetics and scientific knowledge of foods: naturopathy, the vegetarian movement, the Catherine Kousmine method. Diets, more or less scientific, more or less commercial, have also diversified.
Principles of Dietetics: The general principles of Western Scientific Dietetics are as follows.
Energy: quantitative need.
It is generally believed that the energy requirement depends on the climate, age, size and activity of the subject.
However, an isolated study found a paradoxical result: researchers at the University of Leeds in Great Britain estimated in 1997 that there would be no link between the number of calories burned during physical exercise and the number of calories absorbed during meals. They put eight volunteers through an intensive gymnastics program. As a result, they ate just as much on exercise days as they did on rest days.
Energy: qualitative distribution of sources
Foods contain many nutrients. Some of these nutrients (carbohydrates, lipids, proteins) are also sources of energy. To put together balanced menus, you have to know your energy needs and distribute the energy appropriately between the different sources. It is also necessary to provide other non-energetic nutrients (vitamins, minerals, fibers and water) in sufficient quantity.
The energy intake of the main nutrients is calculated by various estimates, such as the indirect calorimetry method. We obtain :
- 1 g of carbohydrates provides 4 kilocalories (kcal), or 17 kilojoules (kJ);
- 1 g of lipids provides 9 kcal, or 38 kJ;
- 1 g of proteins provides 4 kcal, or 17 kJ;

The theoretical distribution of the energy provided by food is as follows in France:
- 50 to 55% of carbohydrates (favoring carbohydrates with a low glycemic index);
- 35 to 40% lipids (including a part of vegetable origin: for example, virgin olive oil);
- 12 to 15% protein (including part of plant origin).

We call "empty calories" the calories found in foods (such as sodas, candy or alcohol) that provide a lot of energy with very few essential non-energy compounds such as fiber, minerals and micronutrients.
Other nutrients: Other elements of nutrition play an important role, including:
- dietary fibers;
- vitamins;
- mineral macro-elements: calcium (Ca), phosphorus (P), potassium (K), chlorine (Cl), sodium (Na), magnesium (Mg);
- mineral trace elements: iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), iodine (I), molybdenum (Mo), etc.
In addition, current science does not take into account, in the 2010 labeling, polyphenols, phytosterols and all the richness of the plant world in plant molecules, the full potential of which remains to be discovered.

Excess of Certain Nutrients and Health: Excessive consumption of certain nutrients can be dangerous. For example sodium in western countries. Its consumption is mainly in the form of sodium chloride (or food salt). The overconsumption of sodium is the cause of water retention in the blood system which leads to high blood pressure.
Ensuring that everyone knows how to put together balanced menus is a public health issue. It is now certain that dietary imbalances are a major source of diseases such as cardiovascular disease, overweight, eye disease, diabetes, osteoporosis and certain cancers.
Spontaneous Application: Dietetics have shown that virtually all local cuisines around the world de facto apply these principles. For example :
- The couscous combines starches (carbohydrates), fiber (four vegetables), meat (fat and protein) and is often accompanied by rotten milk (calcium).
- The Breakfast English, who can understand eggs, bacon free, potatoes fried, sausages, etc. is very high in lipids, but complements well a diet that was traditionally based on porridge in the day.
A distinction must be made between the food consumed by the human species for 7 million years until the Neolithic (and still consumed by the last hunter-gatherers) and that consumed since the Neolithic. Until the Neolithic, the diet mainly included fresh fruits and oleaginous, vegetables, tubers (but not potatoes), meat and fish. There were no dairy products, no cereals, no pulses, no salt, no sugar, no oil. Of course, given the difficulty in obtaining meat, the diet was probably more carbohydrate. On the other hand, our ancestors consumed, in the largest possible quantity, oleaginous fruits which constituted the parallel (in much higher) with our modern oils. With the use of fire and thus the cooking of foods allowing the consumption of starchy foods (tubers, cereals, pulses), life expectancy has increased.

Rational application: meal canteens, school and company restaurants are established taking into account the lessons of dietetics, on the assumption that the meal would consist of:
- in rawness ;
- a garnished dish including a source of animal protein (meat, eggs, fish, offal), a source of cooked vegetables and a source of complex carbohydrates (starchy, cereals or bread);
- a cheese or dairy product;
- of a fruit (or a fruit salad);
- water for hydration (1,5 l / d of drinking water in total).
When these restaurants operate in self-service mode, the meal generally ceases to be balanced within the meaning of official dietetics as soon as one of these dishes is missing, or on the contrary if it is doubled. It also ceases to be so if accompanied by a sweet drink.
Distribution: Dietetics has long been a private matter. But the public health problems posed by food have led the public authorities to intervene in this area.
In Europe, the public authorities are repeating dietetic messages to the attention of the youngest in particular ("eat five fruits and vegetables a day", "do not eat too much fat, too sweet and too salty"), particularly in the context of television programs. An official program (National Health Nutrition Program) is responsible for establishing recommendations and messages intended for the general public.
In Europe, several countries organize the "week of taste" (in France it takes place at the end of October), which notably gives rise to numerous initiatives in schools, has five main values, one of which focuses on dietetics.

Commercial claims: Food companies having sometimes abused quality "diet" to sell their products could soon be banned in Europe from labeling. The health claim is a powerful marketing lever for increasing the consumption of a food by emphasizing a "virtuous" side of its composition, which obscures any imbalances in the food (food that is too fatty and too sweet, which would highlight before its calcium and iron intake, for example).