From the Guidelines
Selenium has been extensively researched, with recent guidelines emphasizing its importance in human health, particularly in relation to antioxidant defense, thyroid hormone metabolism, and immune function. The most recent and highest quality study, 1, published in 2022 in the journal Clinical Nutrition, provides strong consensus recommendations for selenium administration. According to this study, a plasma selenium concentration of <0.4 mmol/L (<32 mg/L) should prompt selenium administration, starting with 100 mg/day, and in patients without an inflammatory response, a plasma selenium concentration of <0.75 mmol/L without abnormal losses should trigger selenium supplements. Some key points to consider when evaluating selenium research include:
- Selenium functions as a component of selenoproteins, playing critical roles in various bodily processes
- The recommended dietary allowance (RDA) for selenium is 55 micrograms per day for adults, with upper tolerable limits set at 400 micrograms daily to avoid toxicity
- Selenium can be obtained through foods like Brazil nuts, seafood, organ meats, and whole grains, with content varying based on soil selenium levels where foods are grown
- Selenium supplements are available in various forms, typically in doses ranging from 50-200 micrograms, but are generally only recommended for those with documented deficiencies or specific medical conditions, as excessive selenium intake can cause selenosis. While earlier studies, such as 1, published in 2002, suggest that selenium may have potential benefits for cancer prevention, the most recent and highest quality study, 1, provides more specific and strong consensus recommendations for selenium administration, which should be prioritized in clinical practice.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Research on Selenium
- Selenium is a trace element that plays a crucial role in the organism, with its deficit causing acute disorders and overdose leading to severe consequences 2.
- The element has antioxidant properties and is an essential part of important antioxidant enzymes, making it effective against the toxicity of many agents and the side effects of drugs 2, 3.
- Selenium administration has been found to be beneficial in protecting the organism against environmental pollutants, drugs, and physical factors, with various forms of selenium being studied, including inorganic and organic compounds and Se-enriched natural products 2, 3.
Selenium and Immune Function
- Selenium affects all components of the immune system, with a deficiency resulting in immunosuppression and supplementation with low doses resulting in augmentation and/or restoration of immunologic functions 4.
- Selenium supplementation has been shown to stimulate the function of neutrophils, production of antibodies, proliferation of T and B lymphocytes, and NK cell-mediated cytodestruction 4.
- However, a systematic review and meta-analysis of experimental human studies found that selenium supplementation did not substantially affect immunoglobulin or white blood cell concentrations, and the dose-response meta-analysis indicated that an increase in plasma selenium concentrations above 100 μg/L did not further increase IgA levels nor T cells 5.
Selenium in Metabolic Diseases
- Selenium has been suggested as a dietary supplement for health benefits, particularly in the management of major chronic metabolic disorders, including hyperlipidaemia, hyperglycaemia, and hyperphenylalaninemia 6.
- Clinical significance of selenium deficiency in chronic metabolic diseases has been elaborated, and clinical and experimental observations of dietary supplementation of selenium in treating chronic metabolic diseases have been summarized 6.
- The mechanism of action of selenium has been proposed via inspecting the interaction of molecular networks and predicting target protein, highlighting the beneficial role of selenium in the dietary management of chronic metabolic diseases 6.