Vitamin B6 (ATC: A 11 HA 02) – a group of 6 organic chemical compounds, pyridine derivatives: pyridoxine, pyridoxal and pyridoxamine and their 5′-phosphates. The biologically active form is pyridoxal phosphate, to which the remaining forms are enzymatically transformed, as a result of the action of kinases and oxidases.
It is a vitamin from group B, it dissolves in water and is a precursor to important coenzymes that control the course of many key biochemical reactions. The use of isoniazid is the most common cause of deficiency of this vitamin.

The role in the body
Vitamin B6 is involved in the transformation of amino acids, facilitates their decomposition, metabolism of fats and carbohydrates, enables the storage of energy, participates in the formation of enzymes, hormones, hemoglobin, participates in the formation of prostaglandins, affects blood pressure, muscle spasms, heart function, proper functioning of the system nervous, increases the body’s immunity, relieves side effects of medications, supports kidney treatment, reduces excessive excretion of oxalic acid in the urine, prevents the formation of kidney stones, helps fight pain and stiffness of the wrist and hand, relieves premenstrual symptoms (effective dose is 50 to 100 mg pyridoxine hydrochloride daily, with 100 mg per day seeming to be more effective). Supports the treatment of seborrheic dermatitis, hair loss, inflammation of the lips and tongue. Despite the conflicting results of research, it is often stressed that supplementation with B6 in the carpal tunnel syndrome can bring significant relief of symptoms with simultaneously low risk for the patient at the recommended doses (up to 200 mg per day). Regularly taking high doses of vitamin B6 significantly reduces the risk of developing Parkinson’s disease in people who smoke. The beneficial effect of magnesium + vitamin B6 on the behavior of children with autism was noted.

The effects of scarcity
Vitamin B6 deficiency can cause nervous system symptoms such as convulsions, depression, apathy, insomnia, general deterioration of well-being, reduced mental performance, and neuritis. Other symptoms of vitamin B6 deficiency include: reduced immunity to infections, inflammation of the skin (seborrheic changes on the face, irritation of the tongue and oral mucosa), anemia, nephrolithiasis, fatigue, nausea, retching, disturbances in the functioning of the myocardium, increased the risk of developing tumors, whereas in children – mental retardation, bone formation abnormalities, epileptic symptoms, irritability. Vitamin B6 deficiency is an important risk factor for atherosclerosis, hence the deficiency of this vitamin increases the risk of stroke and ischemic heart disease.

The effects of excess
Vitamin B6 in high doses is neurotoxic. In some people (very rarely) – anomalies in the functioning of the peripheral nervous system may occur already at 50 mg of pyridoxine hydrochloride per day, used for a sufficiently long time. Long-term taking of doses of vitamin B6 above 200 mg (usually 1000 mg or more) may cause peripheral neuropathy. These changes disappear with the cessation of excessive supplementation with vitamin B6. When taking doses below 200 mg daily, side effects are very rare.
Neurotoxic effects of high doses of vitamin B6 are observed when consumed in the form of pyridoxine, but not for pyridoxal phosphate.

Sources in food
Vitamin B6 is found in a variety of food products. The richest sources include: chickpeas, fish, meat, potatoes and other starchy vegetables, as well as some fruits (eg bananas, but not citrus).

The need for an adult person for vitamin B6 is about 1-2 mg per day. Therapeutically often much higher doses are used, in the range of 50-200 mg per day, and even 2-7 g / day.