Glossary: V

Valeriana officinalis

The sedative properties of valerian have been known since ancient Greece. Hippocrates described its therapeutic properties and Galen later prescribed it as a remedy for insomnia. Today is indicated in cases of anxiety or insomnia, since it resets physiological sleep after 2-4 weeks.

Valerian is an herbaceous plant that reaches 2 meters in height and grows in the temperate regions of Europe and Asia. This species presents an unpleasant odor, which does not take away from its therapeutic properties that have been recognized by the World Health Organization.

The parts of the plant used are the rhizome and roots, rich in active compounds such as valerenic acid, valeranone, gamma-aminobutyric acid (GABA), glutamine, arginine, flavonoids and lignans.


Valerian is indicated as a mild sedative in cases of irritability, nervous excitability and sleep disturbances.

The sedative and calming properties of valerian are due to the combination of several active principles. Valerenic acid acts in the nervous system by facilitating the release of GABA, a neurotransmitter associated with relaxation. Valerian extract contains a small amount of this substance along with glutamine, an amino acid that contributes to the synthesis of said neurotransmitter. As a result, the concentration of circulating GABA increases, thus favoring a state of calmness that makes it easier to fall asleep. The best results are obtained within 2-4 weeks of administering this medicinal plant.

Valerian promotes muscle relaxation, resulting from the effects of the valeranone and valerenic acid. It also decreases alertness within two hours after administration, so it can be useful in cases of stress.

Precautions: Contraindicated in cases of pregnancy, lactation and in children under 3 years old.

Vitamin A

Vitamin A or retinol is a liposoluble vitamin that is essential in protecting the integrity of cell membranes, especially in epithelial and mucosal tissue, and it is also essential for eye health.

It is naturally found in animal products, such as the liver of certain animals, egg yolk or whole milk. Another way to consume vitamin A is from carotenes, which our body is able to transform into vitamin A. These are found in yellow, orange and red plant foods such as carrots or tomato


Vitamin A plays an important role in maintaining the epithelial barrier and the mucous membranes, which represent the immune system’s primary action of defense, helping to reduce the risk of infections from microorganisms. In addition to assisting in the maintenance of the mucosal surface of the skin, it is involved in the activation and stimulation of cells in the immune system.

It plays an important role in maintaining the tissue and functioning of the retina (eye membrane that captures images and sends them to the brain), reducing the risk of night blindness and strengthening weak vision and other eye diseases.

It participates in the growth of teeth, gums and bones, as well as in reproduction processes.

Lastly, it promotes healthy hair and skin due to its role in preserving tissue integrity.

Vitamin C

Vitamin C, or ascorbic acid, is a water-soluble vitamin. It plays a fundamental role in the maintenance of connective tissue and bones.

It is present all throughout nature, with a significant amount found in fresh plant foods such as fruits, especially citrus fruits like oranges or lemons, vegetables such as spinach, or peppers as long as they are eaten raw.


Ascorbic acid is an antioxidant and most of its functions revolve around this property.

It participates in the formation of neurotransmitters (molecules that allow for the passage of information from neuron to neuron) in the nervous system, as well as in the development of gamma-globulins (blood protein that carries antibodies) in the immune system. It increases the response of neutrophils (cells that respond to infections) and increases the development of lymphocytes.

Vitamin C is involved in the synthesis of collagen and carnitine in order to maintain healthy connective tissue and bones, as well as in the formation of bile acids from cholesterol molecules.

It improves the absorption of non-heme iron, which is mainly found in plant foods.

Precautions: An excess of vitamin C may promote kidney stones due to the precipitation of oxalate crystals.

Vitamin D, cholecalciferol

Vitamin D is a fat soluble vitamin that is essential for our body’s health, and is obtained through diet and sun exposure.

This vitamin is found in two different forms: vitamin D2 or ergocalciferol in plants, and vitamin D3 or cholecalciferol in animals, the latter being its active form in humans.

Recent studies have demonstrated the importance of this vitamin outside of the skeletal system, which it has traditionally been associated with, suggesting that cholecalciferol could be a key element in alleviating many ailments.

It is found in foods like egg yolk, or in oily fish such as salmon, tuna or sardines.


Vitamin D performs different functions in the body, the most well-known of which is based on the maintenance of normal levels of calcium and phosphorous through different processes involving the bones, kidneys and intestines, regulating the absorption and excretion processes of these minerals.

This vitamin participates in the formation and replenishment of the bone. It stimulates the reabsorption of calcium via the kidneys that is dependent on the parathyroid gland.

In addition, vitamin D has immunomodulatory properties and the ability to act as a hormone in the body, and its receptor is found in most muscle tissues. On the other hand, it is involved in the endocrine system, where it modulates cell growth and differentiation in many tissues.

Lastly, vitamin D deficiency can lead to osteoporosis in adults and rickets in children.

Vitamin E

Vitamin E or alpha-tocopherol is a fat-soluble vitamin with antioxidant properties. It is absorbed in the duodenum and jejunum in the presence of lipids and bile salts, and its deficiency is rare.

It is naturally present in seed oils (wheat germ, sunflower, corn, soy, peanut…), virgin olive oil and nuts.


Vitamin E is known as an antioxidant. It works by reducing free radicals created by the body. These are substances that can damage cells and accelerate aging. As a result, alpha-tocopherol protects and regulates the fluidity of the cell membrane.

On the other hand, vitamin E regulates platelet aggregation, so it is considered an important nutrient in preventing vascular disorders.

Precautions: Avoid taking vitamin E supplements along with anticoagulant or antiplatelet medications, as it may cause increased bleeding.

Vitamin K, phytonadione

Vitamin K is a fat-soluble element that is necessary for blood clotting. It is mostly found in leafy vegetables such as turnips, broccoli, spinach or lettuce, among others. This vitamin can be synthesized by the intestinal microflora.

We can find vitamin K in three different forms: K1 or phytomenadione, present in green leafy foods, K2 or menaquinone, which is made by the intestinal bacteria, and K3 or menadione, which is a synthetic compound.

A deficiency of this vitamin is uncommon as it is easy to get through our diet. It is mainly found in green leafy vegetables and tomatoes, although it is also found in animal products such as meat and eggs. On the other hand, the microorganisms in our intestinal flora are able to synthesize it endogenously.


Vitamin K plays an important role in blood coagulation as a cofactor lipid. This is why it is sometimes called the antihemorrhagic vitamin or the coagulation vitamin. Vitamin K contributes to normal blood clotting.

It participates in bone maturation, helping a bone protein called osteocalcin to mature, and it also acts as a cofactor of different enzymatic sources for the formation of proteins in the liver. Vitamin K contributes to the normal maintenance of our bones.

Precautions: People taking oral anticoagulants should control the time of consumption and avoid large variations in the levels of this vitamin in the body, as it counteracts the typical treatment effects.