by Caroline St Clare

Created on: July 20, 2011

Selenium is a mineral which is found naturally in many foods. Its powerful antioxidant properties can help boost the immune system and may also help prevent cancer. The importance of the functions of selenium in the body are becoming increasingly well recognized, particularly the role it plays in keeping the body healthy.

What is selenium?

Selenium is a micro-mineral or 'trace element' which should be included in the diet for good health. It is also an

antioxidant, a chemical found in fruit and vegetables which can help protect cells from the damaging effects of free radicals. Free radicals are substances which are generated in the body and used to kill bacteria and fight inflammation. However, if levels of free radicals become too high, they eventually start causing cell and tissue damage. Antioxidants are, in a way, an antidote, which counteracts this damage. Since selenium isn't manufactured by the body, it must be obtained through the diet.

The functions of selenium

The antioxidant properties of selenium can help to protect against certain illnesses including cardiovascular disease. Furthermore, the potency of the antioxidants found in selenium may have the ability to block the action of enzymes which are involved in cell division and growth. This is particularly important in cases of cancer where cells grow in an uncontrollable fashion. Selenium, together with other minerals, can help to build up white blood cells, which are vital for the normal functioning of the immune system. This can give added protection for warding off infections and fighting illness. It also necessary for regulating the thyroid gland which helps determine the rate which the body uses its energy sources.

Foods which contain selenium

Micro-minerals such as selenium can be found in most foods in varying quantities. The level of selenium found in any one food depends on how far removed it is from its original plant form as well as the amount of selenium present in the soil where the plant was grown. Generally, the best sources of selenium can be found in Brazil nuts, fish and shellfish, raisins, poultry, brown rice, wholewheat bread and wheat germ. Further good sources include red meat such as beef, as well as eggs, enriched noodles and cottage cheese. Mineral water and some fortified energy drinks may provide another source of selenium.

Selenium deficiency

The results from National Health and Nutrition Examination Survey (NHANES III-1988-94), indicated that the diets of most Americans provide recommend amounts of selenium. However, researchers in the UK believe UK diets may be lacking in selenium due to low levels of the mineral in farm soil. Others who may be lacking in selenium include those with digestive problems such as Crohn’s disease or gastrointestinal illnesses, as well as those with rheumatoid arthritis or who rely on intravenous nutrition. Consequences of selenium deficiency can include a weakened immune system, increasing the chances of picking up illnesses. Deficiency may also lead to an enlarged heart which is unable to pump blood efficiently.

Selenium is a powerful antioxidant which plays an important role in boosting the immune system, while helping to protect the body against illnesses such as cancer. This essential mineral is only needed in tiny amounts and can be found naturally occurring in a range of foods. Though deficiency is rare, those who are lacking in selenium should endeavor to supplement their diet where possible so as not to miss out on its important nutritional benefits.

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