December 2025 - Seleniumfacts.com

Selenium is a trace element that is essential for good human health. Essential means that selenium is a micronutrient that the body must have but cannot synthesize for itself. Its supply must come from food and, if necessary, from supplements. What the body does synthesize when it has an adequate supply of the element selenium is first the amino acid selenocysteine and then selenoproteins into which the selenocysteine molecules are incorporated [Bai 2024].

Nurse portrays good health — **Good health depends upon adequate selenium intake. In selenium-poor regions, selenium supplementation may be necessary.**

Accordingly, selenium is an indispensable component of selenoprotein P and numerous other selenoproteins. Among these selenoproteins are several vital selenoenzymes, e.g., the glutathione peroxidases (GPxs), the thioredoxin reductases (TrxRs), and the iodothyronine deiodinases (DIOs). Through the activity of the selenoproteins, selenium has many biological functions, i.e., antioxidant activity, anti-inflammatory effects, enhanced immune system function, enhanced reproductive capacity, protection of the cardiovascular system, and regulation of thyroid function. In figure 6 of their paper, Bai et al list the best documented selenoproteins and their known functions [Bai 2024]. read more

Cancer treatment. What do we know at the present time about the effectiveness of selenium as an adjuvant treatment in cancer patients?
In a 2024 systematic review, researchers have evaluated the existing evidence from data from 12 studies with 2,483 adult patients undergoing cancer treatment. The types of cancer included non-Hodgkin lymphoma, head and neck cancer, thyroid cancer, acute myeloid or acute lymphocytic leukemia, stage I non-small lung cancer, breast cancer, cervical and endometrial cancer, prostate cancer, and non-invasive urothelial carcinoma [Krannich 2024].

The researchers’ analysis of the available data does not give a clear picture of the efficacy of selenium administration to adult cancer patients. One reason is that several of the evaluated studies did not report measurements of the patients’ serum selenium levels at the beginning or the end of the study. The studies that did report serum selenium levels used different ways to measure selenium levels. Moreover, the duration of the selenium administration and the type of selenium preparation and the dosage varied from study to study [Krannich 2024]. read more

Milestones in early selenium research

1817 Swedish chemist Jöns Jakob Berzelius discovers selenium

1957 Biochemist Klaus Schwarz shows that selenium in microscopic amounts has a vital importance for mammalian health

1969 Professor J.T. Rotruck discovers that selenium has a biochemical role as a component of the antioxidant enzyme glutathione peroxidase

1969 Professors R.J. Shamberger and D.V. Frost report a possible protective effect of selenium against cancer in humans

1973 Professor J.T. Rotruck identifies the enzyme glutathione peroxidase as a selenium-dependent protein

1977 Professor G.N. Schrauzer publishes cancer mortality correlation studies showing an inverse correlation between dietary intakes of selenium and cancer mortality in 27 countries

1988 Professor G.Q Yang summarizes the lessons learned about the selenium-related endemic diseases Keshan disease and Kashin-Beck disease and about the importance of adequate daily selenium intakes

1989 Professor G.G. Duthie publishes evidence for a role of selenium in the prevention of cardiovascular disease

1993 Researcher W.J. Blot publishes the results of the Nutrition Intervention Trials in Linxian, China, showing that supplementation with a combination of selenium and other antioxidants reduces the risk of cancer

1994 Professor G.N. Schrauzer publishes evidence that selenium is important in the maintenance and therapy of HIV-infected patients

1996 Professor Larry Clark publishes the results of a randomized controlled trial – the Nutritional Prevention of Cancer study -- that shows selenium's cancer-protective effects on colon cancer, lung cancer, and prostate cancer

1997 Professor G.F. Combs summarizes the evidence for the protective effects of selenium against cancer

1999 Professor J.E. Oldfield publishes his Selenium World Atlas, mapping areas of selenium deficiency around the world

2000 Researcher O.A. Levander publishes evidence showing an anti-viral effect of selenium

2002 Researcher R. Gärtner shows that supplementation with selenium reduces inflammation in patients with autoimmune thyroiditis

2002 Researcher Margaret Rayman presents the arguments for increasing selenium intakes to realize selenium’s antioxidant and anti-viral and anti-inflammatory effects as well as selenium’s enhancement of immune function and reproductive success.

Month: December 2025

Selenium Essential for Human Health

Selenium for Adjuvant Cancer Treatment