Vitamins: Essential Nutrients

Vitamins are small nutrient (micronutrient) molecules. They do not provide energy in the form of calories like carbohydrates, proteins, or fats, but are still essential for the proper functioning of the body's biological and physiological processes.

Engaging in regular and intensive physical activity requires significantly increasing vitamin intake. The recommended daily intakes (RDIs or DNRs for Daily Nutritional Value) are calculated based on a sedentary physical activity level. These reference values are not sufficient to meet the micronutrient needs of a regular athlete.

Vitamins play a key role in metabolism. These substances serve as co-factors for almost all biochemical processes by catalyzing the speed of biological reactions. A vitamin deficiency can lead to a slowed metabolism, limiting performance and muscle growth. It is therefore very important to incorporate a variety of fruits and vegetables into your daily diet. However, in most cases, even a diversified diet is not enough to ensure adequate vitamin intake. It is therefore strongly recommended to take a daily oral dose of vitamins in the form of tablets or capsules. But be careful, hypervitaminosis (excess of vitamins in the blood) becomes toxic to the body. In addition, too high dosages of vitamins accelerate cell oxidation by causing oxidative stress.

The Vitamins Vitamins are organic substances that must be supplied to the body in small quantities (from micrograms to milligrams). There are 13 of them and they can be classified into 2 categories:

• The storable vitamins:

Vitamin A - Vitamin D - Vitamin E - Vitamin K These vitamins are storable in the body, just like fats. There are always reserves. Vitamins A/D/E/K are lipid-soluble, meaning they need to be transported by fats, hence the importance of lipids in the diet to allow their transport.

• The non-storable vitamins:

B-group vitamins (B1, B2, B3, B6, B8, B9, B12) - Vitamin C The B-group vitamins and vitamin C are not stored by the body. They must therefore be supplied regularly to maintain proper levels.

Vitamins are essential for muscle growth and recovery. Protein synthesis itself depends on vitamins.

Role of vitamins and main food sources

• Vitamin A (retinols, carotenoids)

Its role

Vitamin A supports protein synthesis and is essential for muscle development. It also plays an important role in vision and immunity. Most interestingly, it has a direct effect on testosterone production.

Where to find it?

Active retinols are found abundantly in animal products such as butter, eggs, milk, cheese, and organ meats. Pro-vitamin A is present in plants in the form of carotenoids: carrots, green vegetables, cruciferous vegetables, peas.

• Vitamin D (ergocalciferol, cholecalciferol)

Its role

It is involved in the regulation of calcium metabolism, helps bones remain solid and rigid. It also modulates immunity and blood pressure. It has anti-inflammatory properties and is linked to testosterone production.

Where to find it?

In fatty fish such as salmon, mackerel, herring, canned sardines, and cod liver oil. By regularly exposing yourself to sunlight.

• Vitamin E (tocopherols)

Its role

Vitamin E is a powerful antioxidant. It protects cells from oxidation, and the body's fats (cell membranes, cholesterol, etc.). It also has anti-inflammatory properties.

Where to find it?

In virgin vegetable oils (olive and rapeseed), nuts (almonds, hazelnuts, peanuts), oilseeds (flax, chia), spinach, and avocado.

• Vitamin C (ascorbic acid)

Its role

It is a powerful antioxidant that works synergistically with vitamin E to fight oxidative stress. It strengthens the skin, tissues and bones by stimulating collagen synthesis. It supports the activity of anabolic hormones. It promotes intestinal absorption of iron, essential for tissue oxygenation. It is involved in the synthesis of carnitine, which helps burn fat to provide energy.

Where to find it?

In fruits and vegetables: strawberry, raspberry, kiwi, citrus fruits, cruciferous vegetables, bell pepper, parsley

• Vitamin B1 (thiamine)

Its role

Thiamine plays a major role in energy production and nerve impulse transmission.

Where to find it?

In red meats, poultry, fish, legumes, oatmeal, brown rice, whole wheat, and brewer's yeast.

• Vitamin B2 (riboflavin)

Its role

Vitamin B2 is essential for energy production. It also plays an indirect antioxidant role.

Where to find it?

The main sources are organ meats, yeast, eggs, dairy products, and fish.

• Vitamin B3 (niacin)

Its role

Vitamin B3 helps us obtain energy. It allows the synthesis of hormones and brain chemical messengers.

Where to find it?

In yeast, liver, meats and fish, eggs