Vitamins are organic molecules (or families of molecules) that participate in many essential processes in our physiology, such as cell growth and regeneration, the immune system or the central nervous system (CNS).
In this article, we will first recall the specific characteristics of vitamins and then we will see, through a glossary, which vitamins are essential for good long-term health .
- The specific characteristics of vitamins
Vitamins cannot be synthesized by the body * and must be supplied through food .
* Certain molecular forms are produced by the body but from precursors of external origin, such as for example beta-carotene called provitamins A.
They act on target functions of the body at very low doses specific to each (hence the definition of specific daily needs), this is the notion of micro-nutrition: molecules present in small quantities but which have a significant impact on good physiological functioning.
Vitamin deficiency disrupts the functioning of the body. Long-term deficiencies can have irreversible effects (e.g. on the nervous system for vitamin B12, scurvy for vitamin C).
It is interesting to note that hormones have characteristics very similar to those of vitamins (targeted actions and at low doses) but that these are synthesized by the body.
Vitamin A or retinol and its derivatives (retinal etc.) are particularly important for the functioning of the eyes (synthesis of eye pigments), bone growth and good hydration of the skin.
Vitamin A intake can come from different sources.
For example, we find food sources of vitamin A in its form of Retinol in animal products, notably fatty fish oils, butter and eggs.
Vitamin A can also come from carotenoids (including Beta carotene) present in large quantities in certain plants (carrots, apricots, spinach, pumpkins) which are precursors that the body knows how to convert into vitamin A. These carotenoids are elsewhere called “Provitamins A”.
Vitamin A deficiency in children can lead to growth disorders, and in adults, the most noted disorders are vision disorders (hypersensitivity to light, near twilight blindness), and skin lesions.
B1, B2, B3, B5, B6, B8, B9 and B12 are the different B vitamins essential to our body.
It should be noted that the same vitamin can be involved in various physiological functions. Some even have very similar properties like B6, B9 and B12.
Vitamin B1 or thiamine
Thiamine or vitamin B1 is involved in carbohydrate metabolism for muscles and brain, alcohol breakdown, energy production and nervous system function.
A vitamin B1 deficiency can lead to the appearance of Gayet-Wernicke syndrome, heart failure (beriberi) or even irreversible neurological sequelae.
Dried vegetables, pork, nuts such as walnuts, offal, whole grains are important sources of vitamin B1.
Vitamin B2 or riboflavin
Vitamin B2 is naturally present in large quantities in all foods of animal origin such as meat, fish and dairy products. Green vegetables also contain it in large quantities.
Riboflavin is essential for eyesight, the production of keratin and red blood cells, iron metabolism and the reduction of fatigue.
Vitamin B2 deficiency remains exceptional.
Vitamin B3 or PP
Vitamin B3 is also called niacin . Foods rich in vitamin B3 are of animal origin, mainly fatty fish (salmon, tuna) and red or white meat.
It interacts in numerous metabolic reactions, particularly linked to hypercholesterolemia, brain function or against atherosclerosis.
Vitamin B5 or pantothenic acid
Pantothenic acid plays a role in the transport of oxygen in the blood, in the metabolism of lipids, carbohydrates and proteins. B5 contributes to normal intellectual performance.
Foods rich in vitamin B5 are raw mushrooms, peanuts, oatmeal, eggs and even offal. Cases of deficiency are very rare.
The term B6 does not designate a single molecule, but six . These are involved in processes related to DNA synthesis, red blood cell production, the immune system, the central nervous system and amino acid metabolism.
To meet your daily needs, you should favor foods rich in vitamin B6 such as bananas, potatoes, rice, fatty fish or even offal.
A vitamin B6 deficiency can cause anemia . It is often associated with symptoms such as depression or mood disorders.
Vitamin B8 or biotin
Vitamin B8 has many names such as biotin, vitamin H or vitamin 7. Each time, it is the same molecule. It is essential because it contributes to the production of energy at the cellular level from nutrients. It also participates in the immune system, gluconeogenesis (sugar production by the liver) and the synthesis of fatty and amino acids.
To avoid vitamin B8 deficiency, eat meat, organ meats, legumes and nuts.
Vitamin B9 or folic acid
Vitamin B9, also called "folic acid", is involved in many functions such as:
- production of amino acids essential for cell growth and renewal;
- synthesis of neurotransmitters (CNS);
- production of red blood cells;
- manufacturing of genetic material.
Vitamin B9 is present in many foods such as orange juice, legumes, nuts, offal, eggs and even “leafy” vegetables.
Vitamin B9 deficiencies are common among pregnant women . The use of food supplements is often prescribed.
Vitamin B12 or cobalamin
Cobalamin participates in the formation of red blood cells, the proper functioning of the nervous system and even the reduction of the risk of cardiovascular disease.
Vitamin B12 plays a key role in pregnant women by helping to increase blood volume during pregnancy. It is also essential for the proper development of the baby's nervous system.
Foods rich in vitamin B12 are mostly of animal origin (offal, seafood, etc.). Plant foods do not provide sufficient amounts of vitamin B12 and all people with totally or predominantly plant-based diets must supplement. There are also other categories with increased risks of deficiency linked to reduced absorption of vitamin B12 (treatment of type 2 diabetes with Metformin, etc.)
The first consequences of a lack of vitamin B12 or a deficiency in adults are numerous: chronic fatigue, reduced appetite, irritability, loss of memory, difficulty moving around. In the long term, damage to the nervous system may be difficult to reverse.
In children (and the fetus), vitamin B12 deficiencies have a significant impact on growth, particularly on their nervous system. Particular vigilance is recommended.
Present naturally in all seasonal fruits and vegetables, vitamin C:
- protects against cellular aging thanks to its anti-oxidant action;
- has a preventive action against cardiovascular diseases, certain neurodegenerative pathologies and certain cancers;
- acts to prevent cataracts;
- stimulates the immune system thanks to its action on the functioning and renewal of white blood cells;
- contributes to the production of collagen, a protein which forms part of the connective tissue of the skin, ligaments and bones.
These are just some of its interactions in our body. To be healthy, you must consume 110 mg every day. A vitamin C deficiency can have consequences such as fatigue, great irritability, or even myalgia.
Vitamin D or calciferol
The main function of vitamin D is to increase blood levels of calcium and phosphorus. These minerals are essential for the robustness of bones at all ages of life, for the contraction of muscles, for the transmission of nerve impulses and even for good coagulation.
Vitamin D can be produced by our body . Twenty minutes in the sun is enough to cover your daily needs. Certain foods are rich in vitamin D such as dark chocolate, fatty fish and dairy products.
Vitamin E has antioxidant properties . These help fight against cellular aging due to free radicals. It would also be involved in the prevention of cataracts and the decline in intellectual faculties linked to aging.
The functions of this organic molecule in the human body are poorly identified. On the other hand, vitamin E is often prescribed as a preventative measure against certain age-related pathologies, cardiovascular diseases or even Alzheimer's disease.
The essential role of vitamin K in blood coagulation and bone metabolism no longer needs to be demonstrated.
Foods rich in vitamin K are mainly fruits and vegetables such as cabbage, spinach, certain oils (olive, rapeseed), kiwis, asparagus or chard.
This glossary will be completed and updated regularly.
The Argalys team