What is selenium?
The essential trace mineral, selenium, is extremely important for our health. Discovered as an element in 1817 and scientists determined the role of selenium in human metabolism by 1960s. The main function of selenium is to produce selenoproteins, a family of proteins that contains selenium in the form of an amino acid. At least 25 selenoproteins has been found and each has different metabolic function in human body.
Selenium has structural and enzymic roles, being best known as an antioxidant and catalyst for the production of active thyroid hormone. It is also needed for the proper functioning of immunity, a key nutrient in fighting against virus and inhibiting HIV progression to AIDS. In addition, selenium is required for healthy sperm production and reduce the risk of miscarriage.
What is selenium deficiency?
A deficiency in selenium is generally rare, since it’s found naturally in many foods. The amount of selenium in plants depends on the amount of selenium in the soil where they were grown. Animal products are the same, selenium amount depends on the foods that the animals ate. The lowest selenium intakes in the world are in certain parts of China, where large proportions of the population have a primarily vegetarian diet and soil selenium levels are very low. Individuals undergoing kidney dialysis and living with HIV also have increased risk of selenium deficiency.
The symptoms of selenium deficiency have been reported with muscular weakness, muscle wasting, and inflammation and damage to the heart muscle. It can lead to poor immune function and cognitive decline. Severe deficiency can result in Keshan disease which is a fatal form of cardiomyopathy that was first discovered in a selenium-deficient region in China.
Selenium health benefits:
1. Antioxidant ability
Selenium is an essential component of glutathione peroxidase, which is one of the most important antioxidant within human body to protect us from free radical damage. Selenium also acts in synergy with the antioxidant vitamins (vitamin C and vitamin E), by regenerating them from their oxidized forms and promoting maximal antioxidant protection to prevent chronic degenerative diseases such as cancer, heart disease, and arthritis.
2. Cancer prevention
The most significant finding is selenium’s association with a low risk of certain kinds of cancer. Studies have observed that people who live in parts of the world where the soil is rich in selenium have lower rates of cancer. In addition, people who have cancer often have low levels of selenium. Because selenium’s antioxidant function, since many oxides are cancer-producing, and cancer cells destroy other cells by releasing oxides. It’s likely to be selenium’s role in glutathione that gives it protective properties against cancer and premature-aging.
3. Immune function
Our body needs selenium for the immune system to work properly. Many nutrients including selenium can help boost white blood cells, which improves the body’s ability to fight illness and infections. According to studies, selenium is also a key nutrient in counteracting the development of HIV. Selenium supplementation has been shown to be useful slowing down the HIV progression to AIDS in patients.
4. Cardiovascular Support
Cardiovascular system covers the whole process that involves our heart, Low selenium concentrations are associated with an increased risk of cardiovascular disease. Some studies show selenium may reduce inflammation and prevents hardening of the arteries. Also, because its antioxidant ability, it can prevent LDL cholesterol from been oxidized and build up plaque in the arteries.
The recommended intake amount for optimum health from NutriSearch Corporation is 150μg per day, which is 100μg more than The Food and Nutrition Center of the institute of Medicine recommends for adults. Most people already consume proper amounts of selenium from a varies diet, consuming more selenium may not be beneficial and reaching upper tolerance limit of 400 μg. No one should exceed recommendations by supplementing with very high doses without consulting physicians.
Food sources high in selenium: Brazil nuts, tuna, sardines, shrimp, beef, turkey, chicken, egg, whole wheat, oatmeal, spinach, green peas, potato, lettuce, milk, peaches, carrots