Biological Importance of Selenium

A very small amount of selenium in the human body is present in almost all soft tissues, except for adipose tissue. Most of it is found in muscles – up to 5000 μg, in the liver – up to 1200 μg, in the blood – up to 1100 μg, in the lungs – up to 180 μg.

Selenium is a component of glutathione peroxidase (an enzyme that inhibits cellular oxidative damage). Selenium is an excellent antioxidant, especially necessary for endothelial cells of blood vessels, and it also acts as an anti-carcinogenic substance that helps protect against the effects of heavy metals (lead, mercury).

Selenium, especially in conjunction with vitamin E, strengthens the immune system, has a positive effect on heart function and blood vessels.

Selenium is essential for the conversion of thyroid hormones from T4 to T3.

The main sources of selenium are cereals (wheat bran, corn, buckwheat), seaweed, oysters, shrimp, olives, olive oil, and garlic.

Consequences of selenium excess:

• hair loss;
• dermatitis;
• nail growth in multiple layers;
• feeling of weakness.

Consequences of selenium deficiency:

• muscle weakness;
• weakened immunity;
• kidney failure.