Selen

Improves the functioning of the immune system, which is a fundamental system of protection of human life.
Brain functioning issues and the degenerative changes in the brain progressing with age will soon be more common than the current epidemic of cancer diseases, as indicated by the increasing number of cases recorded.

Improves the functioning of the immune system, which is a fundamental system of protection of human life.
All countries in the world countries struggle with selenium deficiency resulting from the low selenium content in soil. Therefore, the society has access to food products with low selenium level in a diet. Its deficiency may have tremendous influence on the human body, namely: intensification of degenerative, rheumatic and inflammatory processes, increased risk of atherosclerosis, increased risk of cancer.
Also, low selenium level may induce: depression, myopathy, dystrophy, calcification of muscles, cardiac dysrhythmia, degenerative blood vessels disease, Keshan disease.
In addition, a deficiency of this valuable element was observed in cancer diseases, heart attacks, joints inflammation and prostate diseases.
Therefore, preparations containing selenium are commonly used in treatment of the aforementioned diseases.
Many doctors begin to notice the influence of various factors to which the parents were exposed to in the period of conception and pregnancy. Pesticides, preservatives, pigments used in highly-processed foods, cosmetics, aroma and flavor enhancers, raising agents, emulsifiers, sweeteners, and even detergents and radiation.
Selenium is a microelement necessary for the correct functioning of higher organisms. A daily intake of selenium in adult humans, as recommended by the US National Research Council, oscillates between 50 and 70 μg.
Its biological role became known together with the discovery that it is, inter alia, an indispensable structural ingredient of an active site in many enzymes. Selenium is present in form of selenocysteine in over 30 selenoproteins, e.g. selenium-dependent glutathione peroxidases, selenoprotein P, selenoprotein W, selenoprotein G, and iodotyrosine deiodinase type 1.
This element is considered a necessary factor in protecting cells against oxidative stress. Its use has been previously proved in cardiac diseases and cancer, and it is still used in prevention of these diseases.
A compound of selenium that shows strong activity as a „sweeper” of free radicals and anticancer factor ought to contain selenium in +4 oxidation state, but the absorption and the use of non-organic and organic selenium vary completely.
Food contains selenium(II) mainly in form of selenomethionine and selenocysteine. selenium(II) supplied in this form is built into active sites of enzymes only in a very small percentage. Moreover, a significant percentage of it builds into proteins in a non-specific manner, therefore randomly. Such proteins do not show biological activity attributed to selenium compounds. To build into active sites of enzymes in a specific manner, selenium has to be in IV oxidation state.
It is selenites(IV) in erythrocytes, not selenomethionine or selenocysteine, that react with glutathione to produce the first biologically active form of selenium, namely selenodiglutathione. Selenodiglutathione shows strong anticancer properties and it induces the apoptosis of cancer cells.
One of selenium (IV) selenium supplements is sodium selenite. However, sodium selenite is a very toxic, inorganic compound with its lethal dose being 3mg/kg body mass. Also, it must be noted that using sodium selenite in high concentrations may lead to the necrosis of cells. That is why the high toxicity disqualifies sodium selenite used in preventive care in the majority of preparations all over the world. Therefore, it is obvious that due to its high toxicity, sodium selenite can only be used in prevention in doses not exceeding 0.2 mg per day in humans.
The role of selenium as an antioxidant and factor for use in cancer chemoprevention is very well documented in the literature. The correlation between the selenium content in a diet and the increase in cancer occurrence was shown about 50 years ago. The findings of epidemiological studies suggest that the increased risk of cancer is accompanied by an insufficient selenium intake, while clinical and experimental studies clearly show that selenium protects against cancer development.
It is believed that genome instability, both congenital and induced by exogenous factors (mutagens and carcinogens), is the primary cause of cancer transformation. It has been shown that selenium ceases the formation of covalent adducts of carcinogens from DNA, and slows down the oxidative modification of lipids and proteins. It also modulates cellular and molecular processes, which play a crucial role in ceasing the cell growth in a multistage cancer process.
Currently the knowledge of selenium and its role in genome stability is based mainly on the data obtained from an animal model and in vitro studies, which indicate that the dose and the form of selenium compounds in within the concentration range higher or equal to 10 μmol/1l has various influences on various cellular processes.
40 μg daily dose of Se is considered a minimum demand in healthy adult humans. Daily doses lower than 11 μg of Se put humans at risk of deficiency of this element, and may cause genome instability and cancer development. The daily dose of 100–200 μg of nonorganic Se decreases the damage to genetic material and the cancer occurrence in human. The maximum daily intake is 400 μg of nonorganic Se.
It has been proved that the use of the right selenium concentration may sensitize cancer cells to chemotherapy. The use of selenium together with vitamin E reveals an interesting perspective in preventing the damage to genetic material and the cancer development. One very serious reservation about safe selenium supplementation is the high toxicity of sodium selenite(IV).
There is a great demand for introducing new, less toxic compounds of selenium(IV). Unlike selenites(IV), the synthetic derivatives of organic selenium allow administration of higher selenium(IV) doses, thus enhance chemopreventive activity while avoiding toxic effects.