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Selenium is an essential mineral for the human body.  In appears that a majority of people don't get enough selenium in their diets, although some scientist disputes that claim.  Some research suggests that a higher level of selenium than the recommended level can be beneficial.  It is being studied for a wide variety of diseases.  Selenium may help prevent ALS, arthritis, asthma, GI cancer, lung cancer, liver cancer, prostate cancer, depression, infertility, HIV, infections, lymphedema, pancreatitis, and thyroid diseases.  While much of the research is encouraging, research on all of the possible benefits is still in its early stages and definite conclusions are not possible.  Some studies have found no benefit.  Very large scale studies are under way.

Click on the buttons above for research on Cancer, Heart, Infections, and Prostate.

I think that enough evidence points in a favorable direction that it is reasonable for all adults take 200 micrograms per day as a supplement with 100 mcg for children.  Generally, multivitamins provide a lesser amount.  Also, I do not like multivitamins because of their high vitamin A content.  The 200 mcg. amount of selenium costs about 3-5 cents per day.   I, especially, recommend selenium for asthmatics and HIV patients, as well as people with low levels of meat in their diets.  Since I eat only a modest amount of fish, I take selenium.

It is possible but rare to get too much selenium.  Taking over 450 mcg/day will cause toxicity including brittle nail and hair and a garlic type breath odor.  Some of the benefits of selenium in the diet may be hidden by higher meat intake, which would raise the total selenium intake but simultaneously increase the risk of cancer and heart disease due to other factors.  Also, some areas of the world have lower selenium levels in their soil and thus lower levels in their foods.  

Dietary Intake

Selenium Intake and Blood Levels Low in Ireland: In a study in Ireland, 17% of men and 46% of women reportedly had a low intake of selenium. Blood testing found an average 75 mcg/L instead of an ideal 95 microg/l. Ir J Med Sci 2002 Apr-Jun;171(2):81-4. Selenium is an essential component of the active sites of several enzymes, including glutathione peroxidase, selenium and thioredoxin reductase, which catalyze selenium reactions essential to the protection of cellular components against oxidative and free radical damage.

Selenium Low in Polish Study: In a study of Polish inhabitants, the concentration of selenium in blood plasma was relatively low: about 50-55 microg/l, and the calculated daily dietary intake about 30-40 microg/day. Selenium status of low-selenium area residents: Polish experience. Wasowicz W, Gromadzinska J, Rydzynski K, Tomczak J. Toxicol Lett 2003 Jan 31;137(1-2):95-101

U.S. Selenium Levels Said OK: Third National Health and Nutrition Examination Survey determined the plasma selenium in 17,630 subjects in the United States. Its results claim that more than 99% of the subjects studied were selenium replete = blood level at least 80mcg/L, i.e., they had all the selenium they need. The Institute of Medicine set the Recommended Dietary Allowance for selenium at 55 micrograms per day for adults. Since most estimates of selenium intake in the United States are 80 micrograms per day or greater, routine selenium supplementation was not recommended by the author. Selenium, an antioxidant nutrient. Vanderbilt: Burk RF. Nutr Clin Care 2002 Mar-Apr;5(2):75-9. Ed: The growing number of studies showing benefit from selenium supplementation in the U.S. don't seem to agree with this report.

Dietary Records Unrelated to Selenium Blood Levels: No correlation was observed between the selenium level in serum and estimated selenium intake in a study of 216 adults with 28-day records and food frequency questionnaires. Validity of a self-administered food frequency questionnaire used in the 5-year follow-up survey of the JPHC Study to assess selenium intake: comparison with dietary records and blood levels. Karita K, Sasaki S, Ishihara J, Tsugane S; JHPC. J Epidemiol 2003 Jan;13(1 Suppl):S92-7

Vegans Need Selenium: Selenium is high in beef, its primary source in the U.S. diet. Vegans have a lower than average intake. Am J Clin Nutr 2002 Jul;76(1):100-6. Dietary intake and nutritional status of young vegans and omnivores in Sweden. Larsson CL, Johansson GK. They studied 30 teenage vegans and found no difference in serum iron vs. omnivores, although there was a low intake of vitamins B-12, D, and riboflavin, as well as calcium and selenium. Two had low serum B-12 levels. In Irish adults, selenium came from meat/meat products (30%), bread and rolls (24%), fish/fish products (approximately 11%), and milk and yogurt (9%). Eur J Clin Nutr 2002 May;56(5):402-8 Selenium intakes in 18-64-y-old Irish adults. Murphy J, Hannon EM, Kiely M, Flynn A, Cashman KD.

Mean Daily Intakes in France: Estimated mean daily intakes were 11 microgram for lithium, 3.42 g for sodium, 192 mg for magnesium, 2.03 mg for aluminum, 3.64 g for potassium, 642 mg for calcium, 154 microgram for chromium, 12.3 mg for iron, 2.15 mg for manganese, 4 microgram for cobalt, 74 microgram for nickel, 925 microgram for copper, 10.2 mg for zinc, 147 microgram for arsenic, 66 microgram for selenium, 112 microgram for molybdenum, 3.6 microgram for cadmium, 2.32 mg for tin, 3 microgram for antimony, 9 microgram for mercury and 34 microgram for lead. For the non-essential (toxic) elements, aluminum, tin, antimony, cadmium, arsenic, mercury and lead, the daily intake estimates were far below tolerable limits. Determination of several elements in duplicate meals from catering establishments using closed vessel microwave digestion with inductively coupled plasma mass spectrometry detection: estimation of daily dietary intake. Noel L, Leblanc JC, Guerin T. Food Addit Contam 2003 Jan;20(1):44-56

Selenium Brain Proteins: Glutathione peroxidase has been localized in glial cells, and its expression is increased surrounding the damaged area in Parkinson's disease and occlusive cerebrovascular disease, consistent with its protective role against oxidative damage. Selenoprotein P has been reported to possess antioxidant activities and the ability to promote neuronal cell survival. Recent studies in cell culture and gene knockout models support a function for selenoprotein P in delivery of selenium to the brain. mRNAs for other selenoproteins, including selenoprotein W, thioredoxin reductases, 15-kDa selenoprotein and type 2 iodothyronine deiodinase, are also detected in the brain. J Neurochem. 2003 Jun;86(1):1-12. Selenium and selenoproteins in the brain and brain diseases. Chen J, Berry MJ.

Very High Dose Selenium Caused No Serious Toxicity Over One Year: Intakes of 400 microg/day and plasma selenium of 1000 ng/ml are established as the no observed adverse effect level. 24 men with biopsy-proven prostate cancer randomized to either 1600 or 3200 microg/day of selenized yeast for 12 months were interviewed regarding breath, hair and nail changes. Several liver and kidney function tests and hematology were measured at 6-month intervals. 8 subjects were randomized to the 1600 microg/day and 16 to the 3200 microg/day group. The mean plasma selenium levels achieved with supplementation were 492.2 ng/ml and 639.7 ng/ml for the 1600 and 3200 microg/ day doses, respectively. The 3200 microg/day group reported more selenium-related side effects. Blood chemistry and hematology results were all within normal limits for both treatment groups. More subjects on 3200 microg/day reported symptoms of selenium toxicity; however, these reports did not correspond to peaks in plasma selenium levels. We observed no obvious selenium-related serious toxicities. A report of high-dose selenium supplementation: response and toxicities. Reid ME, Stratton MS, et al Buffalo, NY. J Trace Elem Med Biol. 2004;18(1):69-7.


Alcohol: Vitamin C, Vitamin E and Selenium Combination Protected Against Ethanol-induced Duodenal Injury in Rats. Koyuturk M, et al. Kadir Has University, Turkey. Hum Exp Toxicol. 2004 Aug;23(8):391-8

ALS Helped in DB: In DB studies, selenium was part of a package that helped ALS (Apostolski, Belgrade, J Envir Pathol Toxicol Oncol ’98;17:325

Alzheimer's: Zinc and Selenium appear to Protect Learning and Memory in growing rats exposed to Lead. Lai J, et al. Wei Sheng Yan Jiu. 2004 Mar;33(2):218-20. 

Alzheimer's: Selenium Good; Copper and Aluminum May Not Be for Alzheimer’s: A small study of 140 elderly with Alzheimer’s, vascular dementia, mild cognitive impairment, and controls found positive correlation between cognitive function and Se, Cr, Co and Fe serum levels, while a negative correlation with Cu and Al serum levels. Trace elements and cognitive impairment: an elderly cohort study. Smorgon C, Mari Eet al. University of Ferrara, Italy. Arch Gerontol Geriatr Suppl. 2004;(9):393-402  

Selenium Helped Anxiety in HIV+: In a 12-month DB PC study of 63 HIV+ drug users given selenium 200 mcg/day, 69% had elevated anxiety and 25% moderate depression (BDI over 20). These were not related to current drug abuse, HIV treatment or viral load. Those on selenium had a major increase in vigor (p,.001). and less state and trait anxiety (p=.03). Depression was not affected by selenium. After controlling for antiretroviral therapy, CD4 decline, and education, anxiety was six times more common in the placebo group. Psychological burden in the era of HAART: impact of selenium therapy. Shor-Posner G, Lecusay R, et al. University of Miami. Int J Psychiatry Med. 2003;33(1):55-69

Clozapine Decreases Selenium in Schizophrenics: In a study of 36 depressed, 56 schizophrenic patients on clozapine, 56 other schizophrenic patients, and normals, selenium concentrations in plasma and red cells were found to be significantly lower in schizophrenic patients treated with clozapine as compared with all other groups. Selenium is an essential antioxidant. Its deficiency has been implicated in myocarditis and cardiomyopathy. Low blood selenium concentrations in schizophrenic patients on clozapine. Vaddadi KS, Soosai E, Vaddadi G. Br J Clin Pharmacol 2003 Mar;55(3):307-9

Crohn's Disease: Selenium Decreased: Selenoprotein-P is a selenium-rich serum protein that carries more than 50% of serum selenium. In a study of 20 healthy controls, 34 patients with ulcerative colitis, and 37 patients with Crohn's disease (CD), there was no significant difference in serum selenoprotein-P levels between healthy controls (3.4 mug/mL) and patients with ulcerative colitis (3.0  mug/mL). However, selenoprotein-P levels were significantly lower in CD (1.8 mug/mL). Serum selenoprotein-P levels in patients with inflammatory bowel disease. Andoh A, Hirashima M, et al. Shiga University, Otsu, Japan. Nutrition. 2005 May;21(5):574-9.

Fitness: Two Studies Find No Benefit from Selenium on Performance: Med Sci Sports Exerc ’95;27:390

Genes: Vitamin E with Selenium Protected Rabbit Genes from Anaesthetized with Sevoflurane. Kaymak C, Ankara, Turkey. Hum Exp Toxicol. 2004 Aug;23(8):413-9

Lymphedema From Cancer Helped by Selenium: In a DB study, erisypelas in secondary lymphedema in cancer patients reduced (Austria, Anticancer Res 5/98).

Lymphedema From Cancer and Skin Infection After Mastectomy Helped: Med Klin 9/97;92 Suppl3:50

Mortality: Vitamins C and E with Carotene, Selenium, and Zinc Small Help to Men Only: In a DB PC study of 13,017 French adults a combination of 120 mg of ascorbic acid, 30 mg of vitamin E, 6 mg of beta carotene, 100 mug of selenium, and 20 mg of zinc, compared to a placebo over 7.5 years found no major differences were detected between the groups in total cancer incidence (4.1% for the study group vs 4.5% for the placebo), ischemic cardiovascular disease incidence (2.1% vs. 2.1%), or all-cause mortality (1.2% vs. 1.5%). There was a protective effect of antioxidants in men for all-cause mortality (relative risk, 0.63 in men vs. 1.03 in women;(P = .11 for interaction). The SU.VI.MAX Study: a randomized, placebo-controlled trial of the health effects of antioxidant vitamins and minerals. Hercberg S, Galan P, et al. INSERM/Institut National de la Recherche. Paris, France.. Arch Intern Med. 2004 Nov 22;164(21):2335-42. Ed: Since vitamin E and carotene might increase mortality by roughly 10%, it is possible that the others have more benefit than shown here.

M: Selenium Only Anti-Oxidant Helping Critically Ill in Studies: In an analysis of the 11 best studies the researchers could find, overall antioxidants were associated with a significant reduction in mortality [Risk Ratio (RR) 0.65, p=0.03] but had no effect on infectious complications. Studies that utilized a single trace element were associated with a significant reduction in mortality [RR 0.52, p=0.04] whereas combined antioxidants had no effect. Studies using parenteral antioxidants were associated with a significant reduction in mortality [RR 0.56, p=0.02] whereas studies of enteral antioxidants were not. Selenium supplementation (alone and in combination with other antioxidants) may be associated with a reduction in mortality [RR 0.59, p=0.09] while nonselenium antioxidants had no effect on mortality. Antioxidant nutrients: a systematic review of trace elements and vitamins in the critically ill patient. Heyland DK, Dhaliwal R, et al.Queen's University, Kingston, ONT, Canada. Intensive Care Med. 2004 Dec 17

Pancreatitis Helped by Antioxidants C, E, Se: 28 patients with chronic or recurring non-gallstone pancreatitis were treated in a DB PC trial with placebo or selenium 600, Vitamin E 270 IU, Vitamin C, methionine, and beta-carotene. Six on placebo but none on the anti-oxidants had relapsed in the 20 week study. Uden, UK, Aliment Pharmacol Ther 8/90;4:357

Prematurity & Low Birth Weight Lower Selenium: Prematurity and low birthweight are the best predictors for risk of neonatal hyposeleniemia. 270 neonates studied. Zaragoza. Guirado Gimenez F, Perez Beriain RM, Rebage Moises V, Garcia De Jalon Comet A, Olivares Lopez JL, Baldellou Vazquez A. An Pediatr (Barc). 2003 Aug;59(2):149-54.

Sperm and Fertility Helped by Se, Not A-C-E in DB: DB 69 males with low sperm. Addition of A, C, and E no benefit, but selenium vs. placebo increased sperm motility although not density. Selenium resulted in 11% pregnant vs. 0% for placebo. Glasgow, The effect of oral selenium supplementation on human sperm motility. Scott R, MacPherson A, Yates RW, Hussain B, Dixon J. Br J Urol 7/98;82:76


Asthmatics Treated with Selenium Decreased Corticosteroids 60%: 17 asthmatics put on 200 microg/d of selenium for 2 years had a marked decrease in steroid requirements. Bratisl Lek Listy 2002;103(1):22-5. Decreased consumption of corticosteroids after selenium supplementation in corticoid-dependent asthmatics. Gazdik F, Kadrabova J, Gazdikova K.

Asthmatics Eat Fewer Apples and Have Less Selenium: In a British study, adults with a higher apple consumption had a 12% lower risk of asthma, i.e., a risk ratio of RR 0.88 for asthma. Those with higher selenium had a 16% lower risk, an RR of 0.84. Dietary antioxidants and asthma in adults: population-based case-control study. Shaheen SO, Sterne JA, Thompson RL, Songhurst CE, Margetts BM, Burney PG. Am J Respir Crit Care Med 2001 Nov 15;164(10 Pt 1):1823-8

Selenium, Vitamin C Good to Prevent Asthma: Serum levels of vitamin E, beta-carotene, vitamin C and selenium in 6,153 subjects aged 4 to 16 years were measured to determine any relationship with the prevalence of asthma. There was little or no association of vitamin E with asthma prevalence, but increases in beta-carotene, vitamin C and selenium were associated with a reduction in asthma prevalence of from 10% to 20%. Selenium was particularly protective of kids in homes where smoking occurred. Patricia A. Cassano, Cornell Univ. Am J Respir Crit Care Med 2/1/2004;169:393-398.

Selenium and Iron May Decrease Wheezing and Eczema: In the Avon Longitudinal Study of Parents and Children umbilical cord samples were assayed for trace elements and mineralsn in over 2,100 children, cord selenium was negatively associated with persistent wheeze (OR) per doubling concentration: 0.67). Cord iron was negatively associated with later onset wheeze (OR: 0.86) and with eczema (OR: 0.90). Umbilical cord trace elements and minerals and risk of early childhood wheezing and eczema. Shaheen SO, Newson RB, et al. King's College, London, UK. Eur Respir J. 2004 Aug;24(2):292-7

Selenium and Vitamin Levels Linked to Better Lung Function: Using a random subsample of 479 adults, ages 18-65, from a larger cross-sectional observational study, the association of forced expiratory volume in 1 s (FEV(1)) with plasma copper, vitamin C, vitamin E and serum selenium was assessed. Higher levels of serum vitamin C and selenium appear to be associated with higher FEV(1). The association between higher serum copper and lower FEV(1) was found. Lung function and blood levels of copper, selenium, vitamin C and vitamin E in the general population. Pearson P, et al. University of Nottingham, UK. European Journal of Clinical Nutrition 29 June 2005.


Rheumatoid Arthritis DB Mixed Findings: In a 55-patient 90-day DB PC study of selenium 200mg/day in Brussels, major improvement was found in both groups. The visual analog scale, the Ritchie index, the number of swollen and painful joints, and morning stiffness significantly decreased with time in both groups (p<0.001), but no difference between groups could be identified. When examining the quality of life a significant (p<0.01) improvement in arm movements and health feeling was evidenced in selenium-treated patients. Selenium supplementation in rheumatoid arthritis investigated in a double blind, placebo-controlled trial. Peretz A, Siderova V, Neve J. Scand J Rheumatol 2001;30(4):208-12. Ed: This is a common type of failed study when the placebo group makes major improvement.  In small studies, quirks such as this is the reason even good treatments sometimes appear no better than placebo.

Rheumatoid Arthritis Helped by Selenium, Copper, Zinc, and Vitamin E:  A review article says 60% of rheumatoid arthritis patients were helped by copper injections in open studies. The SOD (Superoxide dismutase) is copper and zinc dependent. The author states that selenium and vitamin E resulted in decreased pain and AM stiffness in a DB study. Analyst 1/98;123:3-6. Ed: Open studies are worthless and should not even be published. 

Rheumatoid Arthritis Helped by Selenium in Patients on Fish Oil: In a 70-patient DB PC study of selenium 200mg/day, researchers found it helps decrease swelling and pain in 3 months and decrease cortisone and NSAID usage. Heinle Med Klin 9/97;92 Suppl3:29

Rheumatoid Arthritis Not Helped by Selenium & Vitamins A, C, and E: DB PC 6 months. UK, Br J Rheum ’90;29:211

Rheumatoid Arthritis not Helped by Selenium: Swedish ’85 study 40 patients for 6 month on 256 microg/d of selenium. Tarp, Scand J Rheum 14:364

Cancer: see Cancer 


Selenium No Impact on Mood: Three small, published studies have suggested an effect of selenium supplementation or deprivation on mood in healthy volunteers. In a much larger 6-month DB PC study of 501 UK adults ages 60-74 randomized to 100, 200 or 300 mug selenium/d as high-selenium yeast or placebo yeast, selenium increased blood levels, but had no affect on total mood or mood-subscale scores or on quality of life scores. Impact of Selenium on Mood and Quality of Life: A Randomized, Controlled Trial. Rayman M, et al. University of Surrey, United Kingdom. Biol Psychiatry. 2005 Sep 19.

Selenium Said to Help Depression: The author claims that there is considerable evidence suggesting that selenium deprivation leads to depressed mood, and that high dietary or supplementary selenium seems to improve mood. Low plasma selenium concentrations in the elderly are significantly associated with senility and cognitive decline. Authors speculate that low selenium may be a cause of increased depression in alcoholics and in patients on dialysis. L. Sher, Riverside, NY, Med Hypotheses 2002 Jul;59(1):89. Ed: I haven't found the "considerable evidence," although I have found what's below.  It's just a little bit of evidence.

Depression Maybe Increased with Low Selenium: Very small 11-patient study with 120 day diets. Biol Psychiatry 1/96;39:121

Depression, Anxiety Less with Higher Intake and with Supplement in DB: 50 healthy adults were studied in a DB. POMS testing for anxiety and depression found more depression, fatigue, and anxiety with lower Selenium and improved on 5 week supplementation. Benton, Biol Psychiatry 29:1092. 1990

Depression: Low Selenium Linked to Low Mood: The authors says that five studies have reported that a low selenium intake was associated with poorer mood. Selenium intake, mood and other aspects of psychological functioning. Benton D. Nutr Neurosci 2002 Dec;5(6):363-74


Conception and Delivery Increased in Sheep and Cows by Selenium: The influences of dietary intakes and supplementation with selenium and vitamin E on reproduction diseases and reproductive efficiency in cattle and sheep. Hemingway RG. Vet Res Commun 2003 Feb;27(2):159-74

Sperm Motility Helped by Selenium-Vitamin E: 54 infertile men treated with selenium 225mcg/d + Vitamin E 400 IU/d or B vitamins for 3 months. Selenium and vitamin E helped. Sperm oxidative stress and the effect of an oral vitamin e and selenium supplement on semen quality in infertile men. Malondialdehyde, marker for lipid peroxidation, reduced by Se-E. Keskes-Ammar L, Feki-Chakroun N, Rebai T, Sahnoun Z, Ghozzi H, Hammami S, Zghal K, Fki H, Damak J, Bahloul A. Arch Androl 2003 Mar-Apr;49(2):83-94

Heart:  see Heart

Infections: see Infections


Kidney Damage by Fluoride Protected by Selenium and Zinc in Rats: Major damage induced by fluoride occurred in the epithelia of proximal renal tubules. The lipid peroxidation might be one of the mechanisms of fluoride toxicity. Na2SeO3 and ZnSO4 could antagonize the renal impairments induced by fluoride through their antioxidation. The cooperative effect of Na2SeO3 and ZnSO4 was more powerful than either Na2SeO3 or ZnSO4 alone. China. Tongji U, Wuhan. Study on antagonistic effects of selenium and zinc on the renal impairments induced by fluoride in rats. Wei Sheng Yan Jiu 2000 Jan 30;29(1):21-3


Halothane Liver Damage in Rats Decreased by Selenium or Vitamin E or Combo: Selenium, vitamin E and their combination may prevent the increase of liver enzymes after halothane anesthesia. J Trace Elem Med Biol 2003;17(1):33-8


Selenium No Help in Acute Pancreatitis: Oxygen free radicals appear in the early phase of acute pancreatitis followed by an imbalance between the oxygen and anti-oxygen system. In a 90-day DB PC study of 70 patients with acute pancreatitis, five patients in the selenium and three patients in the placebo group died. All 17 clinical parameters showed no statistical significance. Investigation of Antioxidant Therapy with Sodium Selenite in Acute Pancreatitis. A Prospective Randomized Blind Trial Lindner D, Lindner J, et al, Chemnitz , Germany .. Med Klin ( Munich ). 2004 Dec;99(12):708-712.


Preeclampsia and Premature Births Higher with Low Selenium: Pregnant women with low selenium levels are 4.4-times more likely to have preeclampsia than women with higher levels.

Prostate: see Prostate 


Selenium and Vitamin E No Help Psoriasis: DB 69 patients given selenium 600 or selenium 600 with Vitamin E or placebo for 12 weeks found no difference in the psoriasis. Fairris, UK, Ann Clin Biochem ’89;26:83

Selenium and Vitamin E No Help for Atopic Dermatitis: DB 60 patients on selenium 600 with vitamin E 600 IU vs. placebo for 12 weeks found no difference. Fairris, Southhampton, Acta Derm Venerol ‘89;69:359

Selenium Decreases Omega-3 Induced Perioxidation: A DB study found selenium increased less in the omega-3 group but selenium helped decrease omega-3 induced perioxidation. No change E or C. Meltzer, U Oslo, Bio Trace Elem Res 10/97;60:51

Selenium Increases Squamous Cell Cancer Slightly: 1312 patients with a history of nonmelanoma skin cancer were in a DB PC study of selenium 200 micrograms with 7 years follow-up. James R. Marshall, Roswell Park Cancer Institute in Buffalo; There was no increased in basal cell cancer. Risk of squamous cell cancer, 25% more likely to develop the malignancy. J Natl Cancer Inst 2003;95:1477-1481.


Goiter and Autoimmune Thyroiditis Blocked by Selenium: 1,900 adults ages 35-60 were studied with thyrotropin, free thyroxine, selenium, zinc, alpha-tocopherol, beta-carotene, retinol, urinary iodine and thiocyanate concentrations measured. Alcohol consumption, smoking, and menopausal status was recorded. Selenium was extremely protective against goiter (OR 0.07). Thyroid tissue was also protected against damage (OR 0.2). In women, there was an inverse association between selenium status and thyroid Volume (P=0.003). Smoking, but not alcohol consumption, was associated with an increased risk of thyroid enlargement in women (OR=3.94). No association between thyroid volume, thyroid structure or selenium was found in men. Association of selenium with thyroid volume and echostructure in 35- to 60-Year-old French adults. Derumeaux H, Valeix P, et al. Eur J Endocrinol 2003 Mar;148(3):309-15

Selenium Lowers T4, T3 in Kittens: A low-selenium diet increases thyroxine and decreases 3,5,3' triiodothyronine in the plasma of kittens. Yu S, Howard KA, Wedekind KJ, Morris JG, Rogers QR. J Anim Physiol Anim Nutr (Berl) 2002 Feb;86(1-2):36-41

Autoimmune Thyroiditis Helped by Selenium: 65 AIT patients in a DB PC study with 200microg/d selenium with all receiving T-4 for 6 months found anti-thyroid peroxidase antibodies decreased 55% with selenium vs. 27% placebo. Effects of a six month treatment with selenomethionine in patients with autoimmune thyroiditis. Duntas LH, Mantzou E, Koutras DA. Eur J Endocrinol 2003 Apr;148(4):389-93; A 3 month German DB PC study of 70 patients found similar results. 47 patients were randomized for another 6 months.  Those continued on selenium had a further large drop in antibodies, those who had been on placebos had a large drop, those switched to placebos had increases in antibodies, and those continuing on placebos remained very high. Selenium in the treatment of autoimmune thyroiditis. Gartner R, Gasnier BC Biofactors. 2003;19(3,4):165-170.

Problems associated with selenium deficiency are still frequently identified in grazing livestock operations. N Z Vet J. 1998 Apr;46(2):54-8.

Thomas E. Radecki, M.D., J.D.