Food sources of selenium

Selenium is a trace mineral that is essential to overall health, and helps to optimize the body’s immune response. Selenium has many vital roles in human body, from antioxidant and anti-inflammatory effects to the production of thyroid hormones.

It is a vital component of many of the body’s enzymes and proteins called selenoproteins, which help to make DNA and protect against cell damage and infections. Selenoproteins are also needed for reproduction and thyroid hormones.

Symptoms of selenium deficiency can include muscle weakness and fatigue. Low selenium status is also associated with an increased risk of poor immune function and cognitive decline.

Selenium is naturally found in the soil but levels vary, hence the selenium content of plant foods varies accordingly. It also can be influenced by the climate and farming practices.

Some great sources of plant-based friendly foods that contain selenium include: Brazil nuts, beans, lentils, wholegrains, and brown rice. Fortified foods are another option, where the mineral is included in wholewheat bread and pasta as well as cereals.

Other good sources of selenium are fish, organ meats such as liver, eggs, and dairy products. Because fish are often exposed to industrial pollution (including mercury), it may be better to choose fish that contain higher levels of selenium, such as sardines.

Selenium can be found across a selection of multivitamins or as standalone food supplements. Women need 60 micrograms a day (+10-20 when pregnant or breastfeeding) and men need 75 micrograms per day.
Food sources of selenium

Selenium roles in immune system

Selenium and zinc are two important minerals that help human immune system function well. Several studies have suggested that being deficient in selenium may be trigger for autoimmune thyroid disease.

Selenium is a trace mineral that human bodies use to produce glutathione peroxidase, and enzyme that’s serves as a natural antioxidant. Glutathione peroxidase works with vitamin E to protect cell membranes from damage caused by free radicals.

Selenium ranks with vitamin C and A as a powerful promoter of immunity. Selenium is an antioxidant key to preventing cancer and stopping the progression of HIV infection from developing into AIDS.

Research suggests that selenium can protect humans against cancer of the lung, ovaries, breast, colon, liver, cervix, skin, stomach and uterus. When sufficient selenium levels are achieved, the risk of getting cancer is half that of a person who is selenium deficient. There are few good food sources of selenium, so supplementation may be the best way to obtain selenium's protective benefits.

One study showed that giving 200 mcg of selenium per day decreased one of the primary antibodies in Hashimoto’s thyroiditis. There is also strong link between selenium deficient and celiac disease.

People with celiac disease have malabsorption of many nutrients, selenium being one of them.

As an immune supportive mineral, selenium stimulates the development and function of all types of white blood cells and enhances the ability of lymphocytes and NK cells, or killer cells, to activate and respond to invaders such as bacteria and viruses, including the flu. Selenium works synergistically with Vitamin E, A and C as an antioxidant.

Selenium binds with many toxic minerals such as arsenic, cadmium, lead, and mercury and facilitates their excretion from the body. By detoxifying per oxidized fats, via its role in the enzyme glutathione and peroxidase, selenium inhibits their carcinogenicity (cancer promoting traits). Selenium also counteracts many of the toxic effects of smoking tobacco.
Selenium roles in immune system

Selenium deficiency

The selenium content of foods is strongly affected by soil characteristics. As a consequence, the selenium content of foods, especially those of vegetable origin, may vary over such a wide range that the use of food composition tables becomes meaningless.

In several regions of the world are exposed to inadequate selenium supplies because selenium contents of surface soils have been depleted by erosion and glacial washout.

The trace element of selenium is involved in thyroid hormone synthesis, metabolism and action.

Selenium deficiency reduces the activity of the selenium dependent deiodinase and peroxidase enzymes and thereby impairs thyroid metabolism in iodine deficient populations.

Cardiomyophathy, cataracts, increased red blood cell fragility, skeletal muscle degeneration, and impaired growth are some of the symptoms of this deficiency.

Selenium deficiency interferes with immune function and predisposes a person to cardiomyopathy that is known as Keshan disease. Keshan disease is a multifocal myocarditis of child-bearing age.

This was discovered in regions of China whose soil is low in selenium content.

Heart disease (cardiomyopathy) of selenium deficiency can be acute or chronic. The acute form shows severe heart failure, shock and deadly arrhythmias.

The other disease associated with selenium deficiency is Kaschin-Beck disease. Kaschin-Becj disease is an osteoarthropathy affecting the epiphyseal and articular cartilage and the epiphyseal growth plates of growing bones.

Borderline deficiency appears to limit the ability to fight viral infections and may predispose a person to some kinds of cancer.
Selenium deficiency