There are a select group of minerals the human body utilizes in order to maintain proper body function, and Selenium happens to be one of them. As a natural substance found in water, some foods, and within the earth’s soil, Selenium is probably best known for its antioxidant properties, and its ability to enhance metabolic function.
While there is speculation that low selenium levels may contribute to the presence of a number of diseases, or increased levels to help fight against others, there has been no scientific evidence to wholly substantiate these claims.
Scientists are still trying to determine the exact role of selenium in the body and the extent in which its presence affects body function, however, most do agree that the mineral does increase the effect of antioxidants, play a significant role in thyroid function and contribute to a healthy antibody response in the immune system.
For instance, when it comes to its antioxidant role, the body uses selenium for the production of enzymes which then act to counter free radicals in the body, much like how glutathione neutralizes free radicals at an intracellular level.
Unlike glutathione, however, which is naturally produced in the body, there is a much greater risk to the body when selenium levels are too high; when the body contains too much selenium, it produces free radicals instead of helping to get rid of them.
As far as thyroid function, selenium is utilized here in the form of selenoproteins. These proteins aid in the off/on function in thyroid hormone production and help in reducing the risk of iodine deficiency.
In the immune system, these same selenoproteins also help to create white blood cells (“functioning” T-cells) which battle antigens in the body – essentially helping to prevent and fight infection.
It has also been shown to improve mood and attitude in patients with this condition. As far as aided in lowering cholesterol, selenium supplementation in the amount of 100-200 mcg per day has shown to decrease cholesterol levels, but this is only in subjects who were selenium deficient to begin with.
It is not yet known if those persons with both high cholesterol and normal selenium levels would benefit in the same way. The research is ongoing.
Most people get their selenium from food sources such as fish, crab, grains and poultry, although the level of selenium in each food is highly dependent on the soil in their respective areas.
There is also a high concentration of selenium found in brazil nuts, oysters, and mushrooms, and you can also find select amounts in beef and pork.