Selenium is a trace mineral that is vital for good health but the body only requires it in small amounts. One of its main activities is its anti-aging properties and its ability to help the body to rid itself of free radicals as well as toxic minerals such as mercury and lead. It is useful for fighting infections as it stimulates increased antibody response to infection, promotes energy levels, assists the male in producing healthy sperms, and helps to alleviate menopausal symptoms in women. In certain cases, it has been shown to help with fighting cold sores and shingles, both caused by the herpes virus. It is also used in the treatment of arthritis and multiple sclerosis, and can help to prevent cancer in adequate amounts. The elasticity of tissue and pancreatic function is also dependent on this mineral. It also helps to make blood less “sticky”, making it useful in helping to prevent heart attacks and stroke.
Plant foods are the main source of selenium in the diet. How much selenium the food contains depends on the amount of selenium in the soil in which it is grown, or animals are raised. Selenium can also be found in some meats and seafood. Animals that eat grains or plants grown in soils with good amounts of selenium will have higher amounts of selenium in their muscle.
Good sources of selenium include:
The recommended daily intake of selenium is 20 micrograms per day for children between 1 and 3. for children between 4 and 8, 30 micrograms is recommended. Between 9 and 13 years, it is 40 micrograms per day of selenium. Those 14 years and over should consume 55 micrograms of selenium per day. When pregnant, 60 micograms of selenium per day is recommended and breastfeeding women should consume 70 micrograms per day.
Most people get the recommended daily intake of selenium. Selenium deficiency is rare but can occur in countries where the selenium content is low in the soil. Selenium deficiency may contribute to a form of heart disease, hypothyroidism, and a weakened immune system. Selenium deficiency can also occur in people that rely on parenteral nutrition as their sole food source. This is a method of feeding a person nutrients through an IV line. Selenium deficiency or depletion can also occur in people that suffer from severe gastrointestinal disorders.
High blood levels of selenium (more than 100 micrograms of daily intake) can result in a condition called selenosis, and symptoms of this include gastrointestinal upsets, hair loss, white blotchy nails, garlic breath odour, fatigue, irritability, and mild nerve damage. Selenium toxicity is rare and the tolerable limit has been set at 400 micrograms per day for adults.
Selenium is present in staple foods such as corn and wheat as selenomethionine, the organic selenium analogue of the amino acid methionine. Selenocysteine is also organic. These are the best utilised form of selenium supplements as it can be incorporated into proteins in place of methionine and serves as a vehicle for selenium storage in organs and tissues. Other options include sodium selenite and sodium selenate – two non-organic forms. Selenium is also available in high selenium yeasts.