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Clayton's Health Facts: Selenium.

Clayton South, SPN (ISSA), is a recognized expert in the bodybuilding / fitness industry with over 150 bodybuilding, fitness and nutrition publications to his credit.

1. What is it and where does it come from?

Selenium is an essential dietary trace mineral1,2 and is a pro oxidant3, that is an essential part of glutathione peroxidase4. It is essential because is serves to activate this antioxidant.

Dietary sources rich in selenium include: brazil nuts, tuna, beef liver, pasta, turkey, cod fish, chicken breast, roast beef, white bread, oatmeal, rice and whole eggs.

2. What does it do and what scientific studies give evidence to support this?

Selenium is a powerful substance and has many applications.

As an antioxidant, selenium provides protection from alcohol induced oxidative stress, thus helping to prevent alcohol-induced liver injury5, and reduces oxidative stress that leads to DNA damage6. Selenium has also been shown to reduce the damage inflicted on the hypocampus by the excitotoxin quinolinic acid7.

Selenium is used in the treatment of many diseases. For example, selenium has been used in the treatment of prostate cancer in men8,9 and although one study has called the cancer fighting and cancer preventing abilities of selenium into question10, ample research has shown that it may moderately reduce the risk of prostate cancer in men11, 12, 13, 14,15,16,17. It has been shown to reduce the occurance of malignant skin conditions18, improve lung function in persons with cystic fibrosis19, reduce the risk for heart disease and cancer20, and offer protection from hyperoxaluria21. Selenium also helps to prevent the onset of dementia in elderly persons22, reduce cell death resulting from ultra-violet radiation exposure23, 24 as well as helping to inhibit the spread of the HIV virus25.

Furthermore, selenium is used in the treatment of cardiovascular disease26, 27, in the treatment of arterial sclerosis28 and in the treatment of aggressive non-Hodgkin's lymphoma29 and chemoprevention30. Because of its NO inhibiting ability selenium is useful in the treatment of anti-inflamatory conditions31 and may protect the heart from inflammation32.

Selenium is an essential dietary mineral because it acts as a catalyst for many physiological processes. Selenium is neccesary for the proper functioning of the thyroid33, 34, 35, 36 and is required for the proper functioning of neutrophils, macrophages, NK cells, T lymphocytes and some other immune system activities37.

It is used in the treatment of male infertility, and can increase the motility and quality38 of sperm and increase the likeleyhood of conception39 Selenium may also protect the female reproductive system from arsenic damage40.

3. Who needs it and what are symptoms of deficiency?

There are no symptoms of difficiency. Everyone can benefit from supplementing with selenium. Populations that may benefit most from the supplementation of selenium include: children, current or recovering alcoholics, arthritics41, women with breast cancer, the elderly, persons with psoriasis42, 43 athletes, persons on diets, vegetarians, and african Americans and Caucasian women living in the southern United States.

Because the infant or adolescent immune system is not as strong as an adults (even when breastfeeding occurs during infancy), the immune system of a young person can be vulnerable to communicable disease and illness. Selenium supplementation is appropriate and safe for children and infants, as selenium is an ingredient in many baby food formulations44,45. In fact, selenium acts as an immune defense agent in both infant, adolescent and adult populations. In adolescents, selenium may prevent gallstones46.

Selenium deficiency has been correlated with immune system weakness47 and cell death48, 49. Immune system weakness often allows pathogens in animals and humans to cause illness.

Keshan disease is a childhood illnesses that results, in part, from a deficiency of selenium50. For growing children and athletes, selenium intake should be of concern as deficiency may result in an increase in protein oxidization51. Children require high levels of protein synthesis for rapid muscular growth. When protein is oxidized by the liver, protein will not reach muscles, and muscular growth and maturation will be stunted. The same holds true for bodybuilders and athletes. Children and adults with severe motor and intellectual disabilities, as well as persons suffering from swallowing dysfunction are often deficient in selenium52, 53.

It has been demonstrated that women with breast cancer are frequently deficient in selenium. Selenium deficiency does not cause cancer, but selenium supplementation will compensate for selenium deficiency in persons with breast cancer54. Newley diagnosed cancer patients should supplement with selenium as they are routinely deficient55.

Selenium has many benefits for elderly persons. Selenium supplementation has been shown to stimulate the production of immune system boosting white blood cells, in elderly populations56.

Bodybuilders and athletes may benefit from selenium supplementation. Many bodybuilders and athletes frequently diet. Persons dieting may become deficient in selenium57. Bodybuilders and athletes on a ketogenic diet may benefit from selenium supplementation, because ketogenic diets are frequently result in vitamin and mineral deficiencies58. Of particular interest to dieting athletes is the fact that selenium deficiency has a negative impact on thyroid function59. To diet successfully, the thyroid must be functioning correctly. It should be noted that using stimulant-based diuretics will not impact blood selenium levels60.

Older athletes can benefit from selenium supplementation61.

As with any restrictive / alternative nutrition regimen, nutritional deficiencies of all varieties may occur. Vegetarians may become selenium deficient as their alternative diets put them at risk for selenium deficiency62.

Southern U.S. African-american and caucasian women of various ages have been found to be deficient in selenium intake. Supplementation will benefit this population63.

4. How much should be taken? Are there any side effects?

Overdosing with selenium can result in renal lesions, loss of fingernails, skin rash, and adverse changes in the nervous system64.

5. Where can I get it?

There are different brand names that manufacture supplemental selenium.


1. Physician Data Query, 2002

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4. Medical Subject Headings, 2003_2003_05_12

5. Sivaram AG, Suresh MV, Indira M. Combined effect of ascorbic acid and selenium supplementation on alcohol-induced oxidative stress in guinea pigs. Comp Biochem Physiol C Toxicol Pharmacol. 2003

6. Dusinska M, Kazimirova A, Barancokova M, Beno M, Smolkova B, Horska A, Raslova K, Wsolova L, Collins AR. Nutritional supplementation with antioxidants decreases chromosomal damage in humans. Mutagenesis. 2003 Jul;18(4):371-6.

7. Santamaria A, Salvatierra-Sanchez R, Vazquez-Roman B, Santiago-Lopez D, Villeda-Hernandez J, Galvan-Arzate S, Jimenez-Capdeville ME, Ali SF. Protective effects of the antioxidant selenium on quinolinic acid-induced neurotoxicity in rats: in vitro and in vivo studies. J Neurochem. 2003 Jul;86(2):479-88.

8. Moyad MA. The use of complementary/preventive medicine to prevent prostate cancer recurrence/progression following definitive therapy. Part II--rapid review of dietary supplements. Curr Opin Urol. 2003 Mar;13(2):147-51.

9. Ponholzer A, Struhal G, Madersbacher S. Frequent use of complementary medicine by prostate cancer patients. Eur Urol. 2003 Jun;43(6):604-8.

10. Vogt TM, Ziegler RG, Graubard BI, Swanson CA, Greenberg RS, Schoenberg JB, Swanson GM, Hayes RB, Mayne ST. Serum selenium and risk of prostate cancer in U.S. blacks and whites. Int J Cancer. 2003 Feb 20;103(5):664-70

11. Shirai T, Asamoto M, Takahashi S, Imaida K. Diet and prostate cancer. Toxicology. 2002 Dec 27;181-182:89-94.

12. Klein EA, Thompson IM, Lippman SM, Goodman PJ, Albanes D, Taylor PR, Coltman C. SELECT: the selenium and vitamin E cancer prevention trial. Urol Oncol. 2003 Jan;21(1):59-65.

13. Duffield-Lillico AJ, Dalkin BL, Reid ME, Turnbull BW, Slate EH, Jacobs ET, Marshall JR, Clark LC; Nutritional Prevention of Cancer Study Group. Selenium supplementation, baseline plasma selenium status and incidence of prostate cancer: an analysis of the complete treatment period of the Nutritional Prevention of Cancer Trial. BJU Int. 2003 May;91(7):608-12

14. Klein EA, Lippman SM, Thompson IM, Goodman PJ, Albanes D, Taylor PR, Coltman C. The selenium and vitamin e cancer prevention trial. World J Urol. 2003 May;21(1):21-7. Epub 2003 Mar 08.

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20. Santhosh Kumar M, Selvam R. Supplementation of vitamin E and selenium prevents hyperoxaluria in experimental urolithic rats. J Nutr Biochem. 2003 Jun;14(6):306-313.

21. Berr C. Oxidative stress and cognitive impairment in the elderly. J Nutr Health Aging. 2002;6(4):261-6.

22. Rafferty TS, Beckett GJ, Walker C, Bisset YC, McKenzie RC. Selenium protects primary human keratinocytes from apoptosis induced by exposure to ultraviolet radiation. Clin Exp Dermatol. 2003 May;28(3):294-300.

23. Rafferty TS, Green MH, Lowe JE, Arlett C, Hunter JA, Beckett GJ, McKenzie RC. Effects of selenium compounds on induction of DNA damage by broadband ultraviolet radiation in human keratinocytes. Br J Dermatol. 2003 May;148(5):1001-9.

24. Foster HD. Why HIV-1 has diffused so much more rapidly in Sub-Saharan Africa than in North America. Med Hypotheses. 2003 Apr;60(4):611-4.

25. Berger MM, Mustafa I. Metabolic and nutritional support in acute cardiac failure. Curr Opin Clin Nutr Metab Care. 2003 Mar;6(2):195-201.

26. Alissa EM, Bahijri SM, Ferns GA. The controversy surrounding selenium and cardiovascular disease: a review of the evidence. Med Sci Monit. 2003 Jan;9(1):RA9-18.

27. Konovalova GG, Lisina MO, Tikhaze AK, Lankin VZ. A Complex of Antioxidant Vitamins Effectively Inhibits Free-Radical Oxidation of LDL Phospholipids in Blood Plasma and Membrane Structures of the Liver and Myocardium. Bull Exp Biol Med. 2003 Feb;135(2):143-6.

28. Last KW, Cornelius V, Delves T, Sieniawska C, Fitzgibbon J, Norton A, Amess J, Wilson A, Rohatiner AZ, Lister TA. Presentation serum selenium predicts for overall survival, dose delivery, and first treatment response in aggressive non-Hodgkin's lymphoma. J Clin Oncol. 2003 Jun 15;21(12):2335-41.

29. Ip C, Dong Y, Ganther HE. New concepts in selenium chemoprevention. Cancer Metastasis Rev. 2002;21(3-4):281-9.

30. Guzman DC, Ruiz NL, Mejia GB, Garcia EH, Vazquez IR, Del Angel DS, Ramirez AM, Olguin HJ. Antioxidant effects of selenium in rat brain and the stimulating role of nitric oxide. Nutr Neurosci. 2003 Jun;6(3):177-82.

31. De Souza AP, De Oliveira GM, Vanderpas J, De Castro SL, Rivera MT, Araujo-Jorge TC. Selenium supplementation at low doses contributes to the decrease in heart damage in experimental Trypanosoma cruzi infection. Parasitol Res. 2003 Jul 22 [Epub ahead of print].

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36. Ferencik M, Ebringer L. Modulatory effects of selenium and zinc on the immune system. Folia Microbiol (Praha). 2003;48(3):417-26.

37. Keskes-Ammar L, Feki-Chakroun N, Rebai T, Sahnoun Z, Ghozzi H, Hammami S, Zghal K, Fki H, Damak J, Bahloul A. Sperm oxidative stress and the effect of an oral vitamin e and selenium supplement on semen quality in infertile men. Arch Androl. 2003 Mar-Apr;49(2):83-94.

38. Scott R, Macpherson A, Yates RWS, et al. The effect of oral selenium supplementation on human sperm motility. Br J Urol 1998;82:76â€"80.

39. Chattopadhyay S, Pal (Ghosh) S, Ghosh D, Debnath J. Effect of Dietary Co-Administration of Sodium Selenite on Sodium Arsenite Induced Ovarian and Uterine Disorders in Mature Albino Rats. Toxicol Sci. 2003 Jul 25 [Epub ahead of print].

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41. Serwin AB, Wasowicz W, Gromadzinska J, Chodynicka B. Selenium status in psoriasis and its relationship with alcohol consumption. Biol Trace Elem Res. 2002 Nov;89(2):127-37.

42. Serwin AB, Wasowicz W, Gromadzinska J, Chodynicka B. Selenium status in psoriasis and its relations to the duration and severity of the disease. Nutrition. 2003 Apr;19(4):301-4.

43. El-Arab AE, Bruggemann J. Selenium composition of cereal-containing infant formulas: assessment of dietary intake status. Int J Food Sci Nutr. 2003 May;54(3):175-80.

44. Carver JD. Advances in nutritional modifications of infant formulas. Am J Clin Nutr. 2003 Jun;77(6):1550S-1554S.

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46. Jackson MJ, Broome CS, McArdle F. Marginal dietary selenium intakes in the UK: are there functional consequences? J Nutr. 2003 May;133(5 Suppl 1):1557S-9S.

47. Nunes VA, Gozzo AJ, Juliano MA, Cerqueira C sar M, Sampaio MU, Sampaio CA, Ara jo MS. Antioxidant dietary deficiency induces caspase activation in chick skeletal muscle cells. Braz J Med Biol Res. 2003 Aug;36(8):1047-53. Epub 2003 Jul 23.

48. Saito Y, Yoshida Y, Akazawa T, Takahashi K, Niki E. Cell death caused by selenium deficiency and protective effect of antioxidants. J Biol Chem. 2003 Jul 29 [Epub ahead of print].

49. Beck MA, Levander OA, Handy J. Selenium deficiency and viral infection. J Nutr. 2003 May;133(5 Suppl 1):1463S-7S.

50. Moskovitz J, Stadtman ER. Selenium-deficient diet enhances protein oxidation and affects methionine sulfoxide reductase (MsrB) protein level in certain mouse tissues. Proc Natl Acad Sci U S A. 2003 Jun 24;100(13):7486-90. Epub 2003 Jun 05.

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53. Lopez-Saez JB, Senra-Varela A, Pousa-Estevez L. Selenium in breast cancer. Oncology. 2003;64(3):227-31.

54. Postovsky S, Arush MW, Diamond E, Elhasid R, Shoshani G, Shamir R. The prevalence of low selenium levels in newly diagnosed pediatric cancer patients. Pediatr Hematol Oncol. 2003 Jun;20(4):273-80.

55. Peretz A, Néve J, Desmedt J, et al. Lymphocyte response is enhanced by supplementation of elderly subjects with selenium-enriched yeast. Am J Clin Nutr 1991;53:1323â€"8.

56. Paeratakul S, York-Crowe EE, Williamson DA, Ryan DH, Bray GA. Americans on diet: results from the 1994-1996 continuing survey of food intakes by individuals. J Am Diet Assoc. 2002 Sep;102(9):1247-51.

57. Bergqvist AG, Chee CM, Lutchka L, Rychik J, Stallings VA. Selenium deficiency associated with cardiomyopathy: a complication of the ketogenic diet. Epilepsia. 2003 Apr;44(4):618-20.

58. Zimmermann MB, Kohrle J. The impact of iron and selenium deficiencies on iodine and thyroid metabolism: biochemistry and relevance to public health. Thyroid. 2002 Oct;12(10):867-78.

59. da Cunha S, Albanesi Filho FM, da Cunha Bastos VL, Antelo DS, Souza MM. Thiamin, selenium, and copper levels in patients with idiopathic dilated cardiomyopathy taking diuretics. Arq Bras Cardiol. 2002 Nov;79(5):454-65.

60. Kujala UM, Sarna S, Kaprio J. Use of medications and dietary supplements in later years among male former top-level athletes. Arch Intern Med. 2003 May 12;163(9):1064-8.

61. Eves A, Gesch B. Food provision and the nutritional implications of food choices made by young adult males, in a young offenders' institution. J Hum Nutr Diet. 2003 Jun;16(3):167-79.

62. Lewis SM, Mayhugh MA, Freni SC, Thorn B, Cardoso S, Buffington C, Jairaj K, Feuers RJ. Assessment of antioxidant nutrient intake of a population of southern u.s. African-american and caucasian women of various ages when compared to dietary reference intakes. J Nutr Health Aging. 2003;7(2):121-8.

63. Zhu YS, Xu HB, Huang KX, Hu WH, Liu ML. A study on human urine in a high-selenium area of China by 1H-NMR spectroscopy. Biol Trace Elem Res. 2002 Nov;89(2):155-63.

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