Selenium is an essential trace mineral required for the normal function of the body and metabolism. Selenium is mostly found in the form of selenoproteins which have a multifunctional role. Its daily requirement to the human body is minimal however excessive amounts may lead to selenium toxicity. Selenium deficiency may lead to several health conditions like cardiovascular disease, impaired immunity and metabolism, infertility, and cognitive decline.
Functions of Selenium
The available form of selenium in the human body is selenoproteins which are essential for the proper functioning of the body. Selenium acts as a cofactor to the enzymes responsible for the deiodination of thyroid hormone. It also acts as an antioxidant and crucial in the expulsion of free radicals from the body. In addition to this selenium deficiency affects the immunity system and progression of HIV to AIDS.
What is Selenium Deficiency?
Selenium deficiency is caused by the prolonged deprivation of selenium intake which may primarily be caused by the unavailability of a selenium-rich diet and secondly, the malabsorption due to the presence of certain health conditions like phenylketonuria & gastrointestinal disorders.
Selenium works as antioxidants along with vitamin E to remove free radicals from the body. Its deficiency can cause impaired immunity, impaired wound healing, and very rare disorders like Keshan disease and Kashin-Beck disease.
Causes of Selenium Deficiency
The condition of selenium deficiency can be developed due to various factors. Some of the major cause has been illustrated below:
- Inadequate Diet: The long-term deprivation of a selenium-rich diet is the common cause of its deficiency. The major source of selenium is animal products that rely on a selenium-rich plant diet. The availability of selenium-rich food items is scarce in certain regions.
- Unavailability of Nutritious Food: Selenium deficient soil can be another cause of the availability of selenium-deficient food items. It occurs in different geographies and can be resolved with selenium-rich fertilisers and fortified seeds.
- GI Disorders: Selenium is mostly stored in the form of protein. However, its absorption is affected by gastrointestinal surgeries like bariatric surgeries. It can also be caused by small intestine tract infections.
In addition to the major causes mentioned above, selenium deficiency can also be caused by phenylketonuria.
Symptoms of Selenium Deficiency
The common symptoms of Selenium deficiency include:
- Muscle weakness
- Hair loss
- Impaired Immunity
Health Risks due to Low Selenium
- Keshan Disease: Keshan disease is associated with selenium deficiency. It is a very rare heart disease that causes heart failure, heart enlargement, abnormal electrocardiogram, heart rate abnormalities, and even cardiac shock. It is generally observed in pregnant women and children with a morbidity rate of more than 50%.
- Impaired Thyroid Regulation: Selenium acts as cofactors of the enzymes responsible for deiodination. The conversion of inactive thyroid (T4) to active thyroid (T3) depends upon the presence of selenium in the body.
- Impaired Immunity: Selenium deficiency compromises immunity. It can lead to immune deficiency diseases like AIDS and. Impaired wound healing and frequent infections are other outcomes of selenium deficiency.
- Free Radicals: The metabolism activity constantly releases free radicals due to oxidation however, it can be removed by the presence of micronutrients with antioxidants properties. Selenium works in the association of vitamins in removing free radicals from the body.
- Male Infertility: Selenium is essential for the biosynthesis of testosterone in the body and affects the production of normal sperm. A large concentration of selenium is present in testicular tissues and its deficiency affects male fertility.
- Cognitive Impairment: It has been observed that selenium deficiency may lead to very rare cognitive disorders like Kashin-Beck disease.
The effect of selenium regarding cancer is being studied however there is not much success in this field.
Tests for Selenium Deficiency
Selenium is the trace mineral present in the body. It is mainly available as a cofactor with several proteins and enzymes.
- Glutathione Peroxidase: It’s very difficult to diagnose selenium deficiency because there isn’t any test available for it. However, in several cases the level of glutathione peroxidase, a selenoprotein is measured to identify the deficiency of selenium.
However other indirect methods like scalp hair and nails are used for the identification of selenium deficiency. These methods are more convenient than the serum test.
Remedies of Selenium Deficiency
- Selenium Supplements: The clinical remedy of selenium deficiency are to take selenium supplements. If you are diagnosed with severe Selenium deficiency, you should consider medical supplements under the supervision of doctors. As higher Selenium may lead to selenium toxicity.
- Selenium Rich Diet: The simple way to prevent selenium deficiency is to intake selenium-rich food items in a daily diet. Some of the selenium-rich food items are nuts, sardines, ham, pork, beef, turkey, chicken, fish, shellfish, and eggs.
- Fortified Food Items: Several agricultural lands across the globe are poor in micronutrients which produces nutrient deficient food items. It can be overcome by selenium-rich fertilizers and fortified seeds.
Prevention of Selenium Deficiency
It is often said that “Prevention is better than Cure” and indeed this is very much true about micronutrient deficiencies. Selenium deficiency can be prevented through the consumption of Selenium rich diet.
Adequate Intake (>19 yrs.):
A simple way to prevent Selenium deficiencies is to maintain recommended daily intakes. The intakes of selenium vary with the different age groups however, the recommended daily intake of selenium for an adult is 400 micrograms.
Selenium is an essential trace mineral required to perform multifactorial roles for the proper function of the body. It acts as a cofactor for several proteins and enzymes responsible for regulating the endocrine system, male fertility, and improved immunity. Selenium deficiency causes rare diseases like Keshan which is related to the function of the heart and Kashin-Beck disease which is associated with cognitive impairment.
Although Selenium deficiency has several ill effects, it can be treated with the right consultation and medical supplements as prescribed by medical experts however, a high concentration of selenium may be deadly. The best possible way to avoid these complications by consuming an adequate amount of Selenium as per RDA through various Selenium-rich diets.