The need of man in vitamins was formed in the process of his evolution which took many ages and corresponds to the quantity that our ancestors traditionally received with diverse food to satisfy their considerable consumption of energy and their way of life.
As a result of abrupt reduction of energy consumption determined by technological and social progress of the last decades the diet of modern man changed. Being sufficient in terms of calorie content to cover the consumption of energy, it can not fully satisfy our need in vitamins. Calculations show that even the most balanced and diverse diet for 2500 Kcal, which complies with average energy consumption of modern man is 20-30% deficient in the majority of vitamins. In order to provide our organism fully with all the necessary vitamins we should either include products additionally enriched with vitamins in our diet or take polyvitamin products in doses, which complete the insufficient consumption of vitamins with food [11, 12].
Avitaminosis at present time is rather rare. Hypovitaminosis is more prevalent, being the risk factor for the development of pathologies on the one hand, and complicating the clinical course of internal diseases [4, 7, 12].
Considerable number of hypovitaminosis is a result of overdose or side-effects of medical preparations of other pharmacological groups used for the treatment of different pathological states. Acetylsalicylic acid in big doses can increase excretion of ascorbic acid by kidneys and cause the development of C hypovitaminosis with typical clinical presentation. Continuous use of peroral contraceptives results into reduction of ascorbic acid and piridoxine level in the organism. The deficiency of vitamin B6 is caused by long-continued use of antibiotics, sulfonamides, ftivazidum, isoniazidum, cycloserinum (antituberculous remedies) [2, 9].
Vitamin therapy today is not limited by prevention of hypovitaminosis, it is also an integral part of pharmacotherapy of many illnesses. That’s why, the right choice of preparation and its dosage is a problem for specialists. On the Russian pharmaceutical market there is a great number of vitamin products in the form of medical remedies and bioactive food supplements which are rather different in terms of their qualitative and quantitative composition and product form [4, 5].
There are no sufficient, from scientific point of view, validation criteria of optimal dose of vitamins in this or that product, the most effective combination of different components in polyvitamin preparations. There are no recommendations concerning the dose size and the frequency of its application based on evaluation of vitamin concentration level in blood plasma of patients. Laboratory methods for the control of vitamin concentration in blood plasma remain unavailable for the majority of population.
At present time both patients and doctors prefer vitamin complexes prevalent on the pharmaceutical market. As a rule, a product containing the fullest set of vitamins in doses from 50 to 100% of average daily norm in combination with micro- and/or macroelements is recommended .
The existing tendency in vitamin and mineral and polyvitamin complexes is justified, on the one hand, in the sense that it improves the quality of a patient’s life – he gets an opprtunity to take all the necessary daily dose of vitamins and microelements in one tablet, on the other hand, it provides a possibility of complex influence on different stages of metabolism.
Modern research held on higher methodological level with modern techniques applied showed that the use vitamin and mineral and polyvitamin complexes is not as effective as we used to think. It can be explained by various interactions, which take place both between the vitamins and/or vitamins and macro- or micro-elements [7, 9, 13].
According to the results of our own research, held on healthy volunteers, most fully the vitamins are assimilated from monopreparations. Adding other vitamins to the complex leads to decrease of vitamins C and B6 absorption. Adding macro- and microelements affects the absorption of these vitamins even more.
The value of maximum concentration in case vitamin B6 is taken as a monopeparation significantly exceeds the same characteristic in case the vitamin is taken as a part of polyvitamin complex, which, in its turn, is obviously higher as compared to the vitamin being the part of vitamin and mineral complex.
The calculations showed that the area under the curve concentration-time is the greatest if vitamin B6 is taken as a monopreparation, the minor – in case of polyvitamin complex and minimum – as a part of vitamin and mineral complex.
From literature we know the facts of such interactions, which inhibit absorption or exchange of vitamins in the organism. Thus, vitamin C affects the assimilation of vitamin B12 from food or food supplements [21, 23, 24, 25] Simultaneous use of vitamins B1 and B12 is not recommended as far as cyancobalamin facilitates manifestation of allergic reactions caused by thiamine. .
However, it would have been a mistake to arrive at a conclusion that the use of monocomponent products is the most appropriate as on the one hand at present time isolated hypovitaminosis is rather rare (polyhypovitaminosis is more frequent), on the other hand the synergism in a number of vitamin and/or micro- and macroelement combinations is a positive proof [2, 5, 12].
It is shown that vitamin C has a saving effect on vitamin E and ?-carotene protecting them from being destructed by free radicals. Vitamin C is a protector of folic acid reductase. Antioxidative effect of vitamin E is potentiated when combined with ascorbic acid, retinol, flavonoids.
Vitamin B1 has vitamin-C-saving function and creates more favourable conditions for the use of vitamin C by enzyme systems of the organism .
Riboflavin is necessary to transform tryptophan into nicotinic acid and piridoxine. Biotin is a synergist of vitamins B2, B6, A, nicotinic acid. Simultaneous use of vitamins B6, B9, B12 causes a more expressed reduction of homocysteine level in blood plasma of the patients [2, 5, 6, 9, 26].
Physiological function of macro- and microelements in the organism of a man as well as their catalytic function in reactions of provitamins activation has served a premise for creating vitamin and mineral complexes, which have spread over.
In metalloenzymatic complexes metall is not fixedly connected with apoenzyme, and in many cases one metall can be substituted by another one. Such metalls are normally called “activators” of corresponding enzymes. Most often enzymes of this type are activated by magnesium where manganese performs as its synergist. In a number of enzymatic reactions calcium and other alkali-earth metalls perform as antagonists of magnesium [3, 5, 19].
On the other hand, it is a well-known fact that even a minor amount of ions of such elements as cobalt, nickel, plumbum, cadmium produce catalytic effect on the oxidative destruction of many vitamins. The following vitamins are sensible to metalls: retinol and its ethers, thiamine chloride, riboflavin, pantothenic acid and its salts, piridoxine hydrochloride, ascorbic acid and its salts, folic acid, cholecalciferol, ergocalciferol, rutine [14, 15, 17].
At present time it has been found that many mineral substances compete with one another on the stages of absorption in intestines.
Calcium competes for absorption with iron, copper, magnesium, plumbum.
Magnesium competes for absorption with iron, zinc, plumbum.
Copper competes for absorption with zinc, calcium, cadmium.
Iron competes for absorption with calcium, magnesium, plumbum, phosphates, zinc, cadmium.
Besides, iron is an antagonist of zinc.
Calcium produces the greatest effect on iron absorption. In case of their simultaneous intake the absorption of iron may reduce 50%, which was determined during research with volunteers .
Phosphates affect calcium, magnesium, copper, plumbum absorption.
Cadmium competes for absorption practically with all macro- and microelements most frequently included into complexes and performs as their antagonist. Zinc, copper, selenium, calcium impede cadmium absorption. [3, 19].
In order to evaluate the real clinical importance of biological synergism and antagonism it is necessary to take into consideration that “competition for absorption” means that one element, which has been received with food and water in high concentration interferes with the absorption if another one (in minor concentration). Having passed the stage of gastrointestinal absorption into the homeostasis system the elements may interact with one another on biological level regardless of their interaction during absorption. Competition for ligand-target may lead both to synergism and antagonism according to the final result of physiological effect.
As a rule, the interaction of medical remedies during absorption develops in case of their simultaneous intake or if the interval between the intakes is less than two hours. Interaction during absorption is especially important for medical preparations with a short period of semiejection (basic watersoluble vitamins). It is possible to eliminate this type of interaction almost fully if you follow more than 4-hour inteval between the intake of components .
Systematization of collected data on vitamin interaction has resulted into creating a new issuing form where dsily dose of vitamins gets into organism in sveral intakes.
This approach is reasonable not only in terms of components interaction, but also in terms of chronopharmacology. For instance, the fact that iodine is better absorbed in the morning is generally known. It is more preferrable to take vitamin D in the evening. Maximum admission of calcium and phosphorus is also noted in the second half of the day.
The new product form of vitamin complexes where the daily dose of necessary vitamins is divided into three intakes allows to avoid antagonism by way of separating interacting components into different tablets, and, vice versa, to facilitate the synergism by means of uniting interacting components in one tablet