Diagnose-Me: Treatment: Selenium

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	Selenium

Selenium
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Selenium is an essential mineral which works closely with vitamin E. Selenium is absorbed fairly easily in the upper portion of the GI tract. Selenium is considered a trace mineral. Found in minute amounts in soil, selenium is considered essential to health. Deficiencies include cardiomyophathy and Keshan's disease. While deaths are rare, low selenium intakes are often seen in countries where the soil is depleted of selenium.

Selenium enters the body when food containing selenium is eaten. The selenium contained in grains and meat is associated with proteins. The human body easily absorbs the organic selenium compounds that are eaten and makes them available where they are needed in the body. The selenium in drinking water is usually in the form of inorganic sodium selenate and sodium selenite, which are also easily absorbed in the digestive tract. The human body can change these inorganic selenium compounds into forms the body can use.

Selenium can build up in the human body, mostly in the liver and kidneys and, to a lesser extent, in the blood, lungs, heart, and testes. It also can build up in hair, depending on the length of time and amount of exposure. Selenium leaves the body mainly in the urine, and less in feces and breath. Selenium in the urine increases as the amount of selenium to which a person is exposed increases.

Selenium closely interacts with vitamin E in the body. The antioxidant properties of selenium are related to this interaction as well as its active selenoprotein involvement in glutathione metabolism. These activities have made selenium one of the key players, albeit in trace amounts, in antioxidant, anti-aging, and immune enhancing products. There are many ongoing research projects investigating selenium, as well as other antioxidants, for the ability to slow the growth of various cancers.

Source

Organic and inorganic forms of selenium may have different properties. Organic forms include selenomethionine, selenocysteine, amino acid chelates, yeast, and kelp-bound selenium. Inorganic forms include sodium selenite and sodium selenate.

Selenium is naturally found in foods high in protein, such as fish, meat, poultry, cereals, seeds and other grains. It can also be found in vegetables like garlic, mushrooms and asparagus. Brazil nuts, especially with their shells on, are very high in selenium. Some experts believe that vegetarians may not be getting enough selenium unless supplemented.

Natural selenium levels in the soil are highly variable throughout the world. In the U.S., the Eastern Coastal Plain and the Pacific Northwest have the lowest selenium levels and people in these regions naturally ingest about 60 to 90mcg per day. This compares to a range of 60 to 200mcg across the U.S. with 125mcg being average.

Reasons For Use

Selenium is useful in the prevention of several cancers. As deficient selenium levels are associated with an increased risk of cancers in general, ensuring adequate selenium intake and maximizing selenium status in the presence of an elevated cancer risk is highly recommended.

Incrementally increasing doses of sodium selenite are being used for decreasing sensitivity to environmental toxins. Your local Naturopath should be familiar with this protocol.

Directions

At the time of writing, there is no clear agreement on how to supplement with selenium - exactly who should use it, how much, or in what form.

The normal intake of selenium in food, about 50-150mcg per day, is enough to meet the daily need for this essential nutrient. Selenium compounds can be harmful, however, at daily levels that are only somewhat higher than needed.

The National Academy of Sciences' Food and Nutrition Board has stated that a daily intake of between 50 to 300mcg of selenium is "safe and adequate". Therapeutic doses often range from 200 to 400mcg daily.

The current USRDA recommendation is between 50 and 200mcg of selenium.

Side-Effects

Toxicity is more of a problem with selenium than most nutrients, and doses over 800 to 1000mcg should be used with caution or under a doctor's supervision only.

The seriousness of the effects of excess selenium depends on how much is eaten and how often. Swallowing a lot of sodium selenate or sodium selenite (for example, part of a bottle of sodium selenate prepared for a flock of sheep, or large numbers of selenium supplement pills) could be life-threatening without immediate treatment.

If amounts of selenium only somewhat higher than needed were eaten over long periods of time, several health effects could occur, including brittle hair, deformed nails, and, in extreme cases, loss of feeling and control in arms and legs. These health effects were seen in several villages in the People's Republic of China where people were exposed to foods high in selenium for months to years. No populations in the United States have been reported with symptoms of serious, long-term selenium poisoning.

There is a warning: "We must be careful not to encourage overconsumption of selenium supplements. While an intake of selenium of around 15mcg per kg of bodyweight per day is thought to be without prolonged impact on human health, it must be remembered that selenium is a toxic mineral with a fairly small therapeutic window. In some sensitive individuals, the maximum safe dietary intake may be as low as 600mcg per day. It would therefore seem prudent to restrict adult intake from all sources to an upper limit of 400-450mcg per day as recommended by several expert panels."

Persons considering supplementation should note that the multivitamins they are taking may already include selenium - in addition to their dietary intake, which tends to be higher in the U.S. than in many countries.