Biochemistry

3. Usage of preservatives that destroy vitamins. 4. Improper storage conditions for products containing vitamins. Secondary hypovitaminosis develops in cases where the ability to digest vitamins decreases or the need for them increases. This may be due to dysfunction of the gastrointestinal tract, difficulty or increase evacuation from it. In infectious diseases, the need for vitamins increases due to their consumption in the process of antibody formation. Treatment with drugs or other methods can increase the need for vitamins as a result of their increased excretion from the body or impaired synthesis in the colon. Thus, for example, antibiotics and other antibacterial substances affect the body. With excess intake of vitamins, they are usually excreted through the kidneys with urine. In some cases, their content rises and hypervitaminosis develops, leading to metabolic disorders. An overdose of vitamins A and D, which is prescribed for children for the prevention of rickets and growth disorders, is especially dangerous in this regard. Vitamin Classification In the process of studying vitamins, at first each of them was given a name for the disease that developed in the absence of this vitamin in food. At the same time, the prefix anti - was added to the name of the corresponding disease, since the introduction of the corresponding vitamin in the diet contributed to a quick recovery (for example, anti-scurvy, anti-anemia, anti-rachitis, etc.). Later, at the suggestion of McCollum (1913), it was agreed to designate individual vitamins as they were isolated in the Latin alphabet: Bi , B 2 , C, etc. Chemical names of vitamins are used after the chemical nature of vitamins was investigated. In 1956, the unified classification of vitamins was approved by the biochemical section of the International Union of Pure and Applied Chemistry (Table 12.1). The systematization of vitamins based on their solubility in water or fats is widespread. One group was water-soluble vitamins, and the other was fat-soluble vitamins. However, for some fat-soluble vitamins, a water-soluble analogue has been synthesized. For example, vicasol is a water-soluble analogue of fat-soluble vitamin K. A number of vitamins are represented not by one, but by several compounds exhibiting biological activity. An example is vitamins of D group. To designate such compounds, use the numbers - D 2 , D 3 . 243