To ensure its proper functioning, the human body requires energy (calories), which is supplied mainly by feeding. The amount of energy required varies from person to person, being influenced by factors such as age, sex and physical activity.

Beyond energy, maintaining good health requires a constant intake of over 40 essential nutrients. These vital elements include proteins, carbohydrates, fats (lipids), vitamins, mineral salts and water

If you want to lose 3 pounds in ONE WEEK, click HERE

Balanced power supply, body fuel

To remain operational, it is imperative that our body receive daily energy (calories) and essential nutrients. It is through the process of digestion, absorption and metabolism of food that we eat that the body extracts and uses this energy and essential nutrients.

 

	Age	Sedentary level	Low level	Active level
Male	19-30 years	2500	2700	3000
	31-50 years	2350	2600	2900
	51-70 years	2150	2350	2650
	71 years +	2000	2200	2500
Women	19-30 years	1900	2100	2350
	31-50 years	1800	2000	2250
	51-70 years	1650	1850	2100
	71 years +	1550	1750	2000

 

The total energy needs of a healthy adult are the sum of three main components:

1. Energy expenditure at rest (DER) : Minimum energy needed to maintain vital functions (breathing, circulation, etc.).

2. Physical Activity: Energy spent during any physical movement or effort.

3. The thermal effect of food (ETA) : Energy used by the body to digest, absorb and metabolize nutrients.

DER and physical activity are the most important factors contributing to these needs.

For patients, the energy needs are more complex, as they include the three factors above, plus the additional need for the disease (metabolic stress, fever, healing, etc.).

To estimate these needs, formulas such as the Harris-Benedict equation or other validated equations are commonly used.

In some specialized establishments, DER can be measured very accurately by indirect calorimetry. This technique analyses the patient's inspired and expired gas concentrations (oxygen and carbon dioxide), providing an accurate estimate of individual energy expenditures and allowing optimal adjustment of dietary treatments.

Role and needs of proteins

Proteins are fundamental elements of the human body. They serve as essential structural components for tissues (muscles, organs), as well as for the manufacture of hormones and many biological liquids. They are crucial for wound healing and maintaining immune functions.

Energy use

Although they are vital for their structural and regulatory functions, proteins can, if necessary, be metabolised to provide energy (calories). However, this energy use is at the expense of their more important functional roles.

Recommended inputs

In medicine, particularly in dietetics, the recommended protein intake is 0.8 to 1 gram of protein per kg body weight.
Example: A 70 kg person will need 56 to 70 g of protein per day.
In case of Disease: Needs increase significantly to support healing and immune processes. In burns or trauma, the intake can be up to 1.5 to 2.5 grams per kilogram is required.

Example: For a 70 kg person, this represents a high need of 105 to 175 grams of protein per day.

Fat requirement

Les graisses constituent habituellement une part importante de notre alimentation, représentant entre 20 % et 40 % de l’apport calorique total journalier. Cependant, dans une optique de prévention des maladies chroniques (comme les maladies cardiovasculaires, l’obésité et certains cancers), il est généralement conseillé de limiter l’apport total en graisses à moins de 30 % de l’énergie consommée quotidiennement.

Sources alimentaires

Les lipides sont présents dans une variété d’aliments, incluant les huiles et les graisses solides (beurre, margarine, etc.).
La viande, le poisson, et la volaille, les produits laitiers.

Acides gras essentiels

Le corps ne peut pas synthétiser tous les types de graisses. Il existe deux acides gras essentiels qui doivent impérativement être fournis par l’alimentation : l’acide linoléique et l’acide alpha-linolénique.