Selenium is a trace element named after Selene, a Greek Goddess of the Moon. It is now considered the most important trace element in our diet, but its importance in human health was only realized 50 years ago.
Selenium is needed for normal cell growth and immunity. It helps to protect against a wide variety of degenerative diseases such as hardening and firming up of arteries, stroke and heart attack. Selenium also enhances the action of a liver enzyme (P450) involved in detoxifying cancer-causing chemicals (carcinogens) and it is also involved in the repair of damaged DNA.
In parts of the world where soil selenium levels are low, the incidence of cancer increases by two- to six-fold. Those with the lowest selenium intake have the highest risk of developing leukemia or cancers of the colon, rectum, breast, ovarian pancreas, prostate gland, bladder, skin and lungs. These risks seem to be even higher if intakes of vitamin E and vitamin A are also low.
Selenium has been shown to prevent the growth of cancer cells in the laboratory and some evidence suggest it is involved in triggering programmed cell death (APOPTOSIS) of abnormal cells.
Lack of selenium is now recognized as a driving force for viral mutations, which may explain why so many new, pathogenic influenza viruses emerge from Asia, where selenium intake is amongst the lowest in the world.
Selenium is vital for the immune system because it stimulates the production of white blood cells; T cells specifically which are natural killer cells, fighting viral and bacterial infections.
Brain health: selenoenzymes have a vital antioxidant role within the brain and the brain receives a priority selenium supply when intakes are low. Selenium may reduce the risk of cerebrovascular diseases by reducing oxidation, vasoconstriction and platelets clumping. Selenium may also protect against senility and Alzheimer’s disease.
So, this amazing trace element has been studied also in relation to its impact on athletes.
Exercise overproduces oxygen reactive species (ROS) and eventually exceeds the body’s antioxidant capacity to neutralize them. The (ROS) produce damaging effects on the cell membrane and contributes to skeletal muscle damage. Selenium (SE) a natural mineral trace element, is an essential component of selenoproteins, that plays an important role in antioxidant defense.
The activity of the enzyme glutathione peroxidase (GPx), a highly efficient antioxidant enzyme, is closely dependent on the presence of selenium. These properties of selenium may be potentially applicable to improve athletic performance and training recovery. We systematically searched for published studies to evaluate the effectiveness of Se supplementation on antioxidant defense system, muscle performance, hormone response, and athletes’ performance among physically active individuals.
An overall evaluation of our current knowledge on this topic, suggests that there is an important relationship between selenium on antioxidant activity. In particular, many researchers foreground this element in the prevention of the harmful effects of free radicals that emerge in exercise. Furthermore, lack of Se is associated with muscle tiredness.
The fact that selenium is abundantly found in the muscle may, be critical in the correlation between selenium and muscle exhaustion in exercise. That selenium has been shown to be important in the immune system also highlights this element in the athlete’s health and nutrition.
Based on this review, it can be concluded that selenium may contribute to an athlete’s health, performance and the maintenance of overall health.