Folic acid is one of the most important vitamins for human health.

The role of folic acid in neurons:

• a significant number of its derivatives, known as folates, are the cofactors of numerous enzymes that participate in the synthesis of amino-acids, i.e. proteins
• participates in the biosynthesis of nucleotides, so it has a key role in the synthesis of DNA and RNY, and on the other hand, defines the division of cells
• affects the activity of genes during the regeneration of nerve cells

Vitamin B12 is necessary for the production of myelin.
It plays a key role in two important biochemical reactions in the human organism:

• formation of methionine through the process of homocysteine methilation
• formation of tetrahydrofolate is necessary for the synthesis of purine and pyrimidine, and thus for DNA and RNY as well, as the secondary products of this reaction

Transformation of L-methylmalonyl coenzyme A into succinyl A coenzyme is of great importance for the formation of the myelin sheath.

Stiffness, numbness and the loss of sensibility are the symptoms that are manifested in peripheral neuropathy caused by the deficiency of vitamin B12.

According to statistical data, between 5% and 20% of adult population suffer from vitaminB12 deficiency, and more than 40% have shown a low level of vitamin B12 in the plasma.

After the absorption, vitamin B6 is transformed into pyridoxal pyrophosphate which is an important cofactor of numerous metabolic reactions of amino acids, glucose and lipids.

In adults, the neuropathy caused due to the deficiency of vitamin B6 starts with numbness, paresthesia or burning pains in the feet, and then, with ascendant propagation, takes the legs and arms.

Neurological examinations point to the presence of polyneuropathy with the weakened distal sensitivity, weakened tendon reflexes, ataxia and mild distal weakness.

Even though vitamin B6 can be found in quite a lot of food, after its treatment, it loses even up to 70% of this vitamin.

On the other hand, vitamin B6 cannot be synthesized, which is why the intake of food and dietary supplements rich in this vitamin are of essential importance

Vitamin B1 is present in most of the plat and animal tissues. It is resorbed in the intestines by a passive diffusion and active transport, and then it is quickly transformed into thyamine diphosphate (TDP) which is physiologically active in the form of vitamin B1.

TDP serves as the main cofactor in oxidation processes (cellular breathing), in the production of adenosine triphosphate (ATP), in the synthesis of glutamate and Y-aminoadipic acids and as a good support in the formation of the myelin sheath.

The deficiency of thiamine leads to the neuropathy known as beriberi which was the first described deficiency syndrome in people.

Fatigue, nervousness and muscular spasms can occur within a few days or weeks as a result of the deficiency of this vitamin in the diet.

Clinical features of the thiamine deficiency start with a distal loss of sensitivity, burning pain paresthesia and muscular weakness in legs and feet.

Vitamin B3 is resorbed in the intestines by a simple diffusion.  Niacin and its derivative nicotinamide (contained in NAD and NADP) are important for metabolism of carbohydrates, fats, proteins as well as for the transfer of intra-cellular signals and the reparation of DNY in cells.

The deficiency of niacin in a diet may cause nausea, skin and labial lesions, anaemia, headache and fatigue.

Pellagra is a disease caused by the deficiency of vitamin B3, and its three classic clinical manifestations are dementia, dermatitis and diarrhoea.