Vitamins - group of low-molecular organic bonds concerning a simple structure and the various chemical nature. It is a national team, in the chemical relation, the group of organic substances united on the basis of their absolute necessity for гетеротрофного of an organism as a component of nutrition. Vitamins contain in nutrition in very small quantities and consequently concern to микронутриентам
The general data
Vitamins participate in set of biochemical reactions, carrying out catalytic function as a part of the active centres of a considerable quantity of various enzymes or acting information регуляторными intermediaries, carrying out alarm functions of exogenous prohormones and hormones
They are not the supplier of energy for an organism and have no essential plastic value. However to vitamins the major role in a metabolism is taken away
Concentration of vitamins in tissues and daily requirement for them are insignificant, but at insufficient entering of vitamins in an organism there come characteristic and dangerous pathological changes.
The majority of vitamins are not synthesised in a human body. Therefore they should regularly and in enough to arrive in an organism with nutrition or in the form of vitaminno-mineral complexes and alimentary additives.
Three basic pathological conditions are bound to disturbance of entering of vitamins in an organism: a vitamin disadvantage - a hypovitaminosis, absence of vitamin - an avitaminosis, and excess of vitamin - a hypervitaminosis
It is known about one and a half tens vitamins. Proceeding from solubility vitamins divide on liposoluble - and water-soluble - all the others. Liposoluble vitamins collect in an organism, and their depots are a fatty tissue Water-soluble vitamins in essential quantities are not deposited, and at excess are deduced. It on the one hand explains that often enough there are hypovitaminoses of water-soluble vitamins, and with another - hypervitaminoses of liposoluble vitamins are sometimes observed
